v2.4.1.9
Document and Entity Information
0 Months Ended
Feb. 26, 2016
Risk/Return:  
Document Type 485BPOS
Document Period End Date Oct. 31, 2015
Registrant Name DELAWARE POOLED TRUST
Central Index Key 0000875352
Amendment Flag false
Document Creation Date Feb. 25, 2016
Document Effective Date Feb. 26, 2016
Prospectus Date Feb. 26, 2016
v2.4.1.9
Equity Oriented or Fixed Income Oriented Funds | The Large-Cap Growth Equity Portfolio

The Large-Cap Growth Equity Portfolio

What is the Portfolio's investment objective?

The Large-Cap Growth Equity Portfolio seeks capital appreciation.

What are the Portfolio's fees and expenses?

The table below describes the fees and expenses that you may pay if you buy and hold shares of the Portfolio.

Annual portfolio operating expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses
Equity Oriented or Fixed Income Oriented Funds
The Large-Cap Growth Equity Portfolio
DPT CLASS
Management fees 0.55%rr_ManagementFeesOverAssets
Distribution and service (12b-1) fees none
Other expenses 0.09%rr_OtherExpensesOverAssets
Total annual portfolio operating expenses 0.64%rr_ExpensesOverAssets
Fee waivers and expense reimbursements [1] none
Total annual portfolio operating expenses after fee waivers and expense reimbursements 0.64%rr_NetExpensesOverAssets
[1] The Portfolio's investment manager, Delaware Management Company (Manager), has contractually agreed to waive all or a portion of its investment advisory fees and/or pay/reimburse expenses (excluding any 12b-1 fees, acquired fund fees and expenses, taxes, interest, expenses, short sale and dividend interest expenses, brokerage fees, certain insurance costs, and nonroutine expenses or costs, including, but not limited to, those relating to reorganizations, litigation, conducting shareholder meetings, and liquidations) in order to prevent total annual portfolio operating expenses from exceeding 0.65% of the Portfolio's average daily net assets from Feb. 26, 2016 through Feb. 28, 2017. The waivers and reimbursements may only be terminated by agreement of the Manager and the Portfolio.

Example

This example is intended to help you compare the cost of investing in the Portfolio with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the Portfolio for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and reflects the Manager's expense waivers and reimbursements for the 1-year contractual period and the total operating expenses without waivers for years 2 through 10. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example (USD $)
1 Year
3 Years
5 Years
10 Years
Equity Oriented or Fixed Income Oriented Funds The Large-Cap Growth Equity Portfolio DPT CLASS
65 205 357 798

Portfolio turnover

The Portfolio pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Portfolio shares are held in a taxable account. These costs, which are not reflected in annual portfolio operating expenses or in the example, affect the Portfolio's performance. During the most recent fiscal year, the Portfolio's portfolio turnover rate was 49% of the average value of its portfolio.

What are the Portfolio's principal investment strategies?

The Portfolio invests primarily in common stocks of growth-oriented companies that the portfolio managers believe have long-term capital appreciation potential and expect to grow faster than the U.S. economy. For purposes of the Portfolio, the portfolio managers will generally consider large-capitalization companies to be those that, at the time of purchase, have total market capitalizations within the range of market capitalizations of companies in the Russell 1000® Growth Index. While the market capitalization of companies in the Russell 1000 Growth Index ranged from approximately $717.61 million to approximately $583.6 billion as of Dec. 31, 2015, the Portfolio will normally invest in common stocks of companies with market capitalizations of at least $3 billion at the time of purchase. The market capitalization range for the Russell 1000 Growth Index will change on a periodic basis. A company's market capitalization is determined based on its current market capitalization. Russell Investment Group is the source and owner of the trademarks, service marks, and copyrights related to the Russell Indexes. Russell is a trademark of the Russell Investment Group.

Under normal circumstances, the Portfolio will invest at least 80% of its net assets, plus any borrowings for investment purposes, in equity securities of large-capitalization companies (80% Policy). The Portfolio's 80% Policy may be changed without shareholder approval. However, shareholders will be given notice at least 60 days prior to any such change.

Using a bottom-up approach, the portfolio managers seek to select securities of companies that have large market opportunities. Companies that have large market opportunities are those that, in our opinion, may have a large demand or market for their goods or services. The portfolio managers also consider a company's operational efficiencies, management's plans for capital allocation, and the company's shareholder orientation. All of these factors give the portfolio managers insight into the outlook for a company, helping the portfolio managers identify companies poised for sustainable free cash-flow growth. The portfolio managers believe that sustainable free cash-flow growth, if it occurs, may result in price appreciation for the company's stock.

Although the Portfolio tends to hold a relatively focused portfolio of between 25 and 40 stocks, it maintains a diversified portfolio representing a number of different industries. Such an approach helps to minimize the impact that any one security or industry could have on the portfolio if it were to experience a period of slow or declining earnings growth.

Because the Portfolio's objective is capital appreciation, the amount of dividend income that a stock provides is only an incidental consideration.

The Portfolio may also invest in other securities, including preferred stock, real estate investment trusts (REITs), warrants, equity and debt securities that are convertible into stocks, debt securities of government and corporate issuers and investment company securities, futures, and options. To the extent that this Portfolio invests in convertible debt securities, those securities will be purchased on the basis of their equity characteristics, and ratings of those securities, if any, will not be an important factor in their selection.

What are the principal risks of investing in the Portfolio?

Investing in any mutual fund involves the risk that you may lose part or all of the money you invest. Over time, the value of your investment in the Portfolio will increase and decrease according to changes in the value of the securities in its portfolio. Principal risks include:

Risk Definition

Market risk

The risk that all or a majority of the securities in a certain market — such as the stock or bond market — will decline in value because of factors such as adverse political or economic conditions, future expectations, investor confidence, or heavy institutional selling.

Foreign risk

The risk that foreign securities (particularly in emerging markets) may be adversely affected by political instability; changes in currency exchange rates; inefficient markets and higher transaction costs; foreign economic conditions; the imposition of economic or trade sanctions; or inadequate or different regulatory and accounting standards.

Real estate industry risk

This risk includes, among others, possible declines in the value of real estate; risks related to general and local economic conditions; possible lack of availability of mortgage funds; overbuilding; extended vacancies of properties; increases in competition, property taxes, and operating expenses; changes in zoning laws; costs resulting from the cleanup of, and liability to third parties resulting from, environmental problems; casualty for condemnation losses; uninsured damages from floods, earthquakes, or other natural disasters; limitations on and variations in rents; and changes in interest rates.

Futures and options risk

The possibility that a portfolio may experience a loss if it employs an options or futures strategy related to a security or a market index and that security or index moves in the opposite direction from what the manager anticipated. Futures and options also involve additional expenses, which could reduce any benefit or increase any loss that a portfolio gains from using the strategy.

Derivatives risk

Derivatives contracts, such as options, futures, and swaps, may involve additional expenses (such as the payment of premiums) and are subject to significant loss if a security or a securities index to which a derivatives contract is associated moves in the opposite direction from what the portfolio manager anticipated. Derivatives contracts are also subject to the risk that the counterparty may fail to perform its obligations under the contract due to financial difficulties (such as a bankruptcy or reorganization).

Credit risk

The risk that an issuer of a debt security, including a governmental issuer, or an entity that insures a bond may be unable to make interest payments and repay principal in a timely manner.

Liquidity risk

The possibility that securities cannot be readily sold within seven days at approximately the price at which a portfolio has valued them.

Investments not guaranteed by
Delaware Management Company
(Manager) or its affiliates

Neither the Manager nor its affiliates noted in this document are authorized deposit-taking institutions for the purposes of the Banking Act 1959 (Commonwealth of Australia). The obligations of these entities do not represent deposits or other liabilities of Macquarie Bank Limited (MBL). MBL does not guarantee or otherwise provide assurance in respect of the obligations of these entities, unless noted otherwise.

How has The Large-Cap Growth Equity Portfolio performed?

The bar chart and table below provide some indication of the risks of investing in the Portfolio by showing changes in the Portfolio's performance from year to year and by showing how the Portfolio's average annual total returns for the 1-, 5-, and 10-year periods compare with those of a broad measure of market performance. The Portfolio's past performance (before and after taxes) is not necessarily an indication of how it will perform in the future. The returns reflect any expense caps in effect during these periods. The returns would be lower without the expense caps. You may obtain the Portfolio's most recently available month-end performance by calling 800 231-8002 or by visiting our website at delawareinvestments.com/institutional.

Year-by-year total return (The Large-Cap Growth Equity Portfolio)

Bar Chart

During the periods illustrated in this bar chart, The Large-Cap Growth Equity Portfolio's highest quarterly return was 16.08% for the quarter ended March 31, 2012 and its lowest quarterly return was -22.25% for the quarter ended Dec. 31, 2008.

Average annual total returns for periods ended December 31, 2015

Average Annual Total Returns Equity Oriented or Fixed Income Oriented Funds The Large-Cap Growth Equity Portfolio
1 Year
5 Years
10 Years
DPT CLASS
5.19% 15.02% 7.99%
DPT CLASS After Taxes on Distributions
1.55% 13.68% 7.33%
DPT CLASS After Taxes on Distributions and sale of Portfolio shares
5.91% 12.09% 6.51%
Russell 1000® Growth Index
5.67% 13.53% 8.53%

Russell Investment Group is the source and owner of the trademarks, service marks, and copyrights related to the Russell Indexes. Russell is a trademark of the Russell Investment Group.
Actual after-tax returns depend on the investor's individual tax situation and may differ from the returns shown. After-tax returns are not relevant for shares held in tax-deferred investment vehicles such as employer-sponsored 401(k) plans and individual retirement accounts (IRAs). The after-tax returns shown are calculated using the highest individual federal marginal income tax rates in effect during the Portfolio's lifetime and do not reflect the impact of state and local taxes.

v2.4.1.9
Label Element Value
Risk/Return: rr_RiskReturnAbstract  
Risk/Return, Heading rr_RiskReturnHeading

The Large-Cap Growth Equity Portfolio

Investment Objective, Heading rr_ObjectiveHeading

What is the Portfolio's investment objective?

Investment Objective, Primary rr_ObjectivePrimaryTextBlock

The Large-Cap Growth Equity Portfolio seeks capital appreciation.

Expense, Heading rr_ExpenseHeading

What are the Portfolio's fees and expenses?

Expense, Narrative rr_ExpenseNarrativeTextBlock

The table below describes the fees and expenses that you may pay if you buy and hold shares of the Portfolio.

Operating Expenses, Caption rr_OperatingExpensesCaption

Annual portfolio operating expenses (expenses that you pay each year as a percentage of the value of your investment)

Fee Waiver or Reimbursement over Assets, Date of Termination rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination
Feb. 28, 2017
Portfolio Turnover, Heading rr_PortfolioTurnoverHeading

Portfolio turnover

Portfolio Turnover rr_PortfolioTurnoverTextBlock

The Portfolio pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Portfolio shares are held in a taxable account. These costs, which are not reflected in annual portfolio operating expenses or in the example, affect the Portfolio's performance. During the most recent fiscal year, the Portfolio's portfolio turnover rate was 49% of the average value of its portfolio.

Portfolio Turnover, Rate rr_PortfolioTurnoverRate 49.00%rr_PortfolioTurnoverRate
Expense Example, Heading rr_ExpenseExampleHeading

Example

Expense Example, Narrative rr_ExpenseExampleNarrativeTextBlock

This example is intended to help you compare the cost of investing in the Portfolio with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the Portfolio for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and reflects the Manager's expense waivers and reimbursements for the 1-year contractual period and the total operating expenses without waivers for years 2 through 10. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Investment Strategy, Heading rr_StrategyHeading

What are the Portfolio's principal investment strategies?

Investment Strategy, Narrative rr_StrategyNarrativeTextBlock

The Portfolio invests primarily in common stocks of growth-oriented companies that the portfolio managers believe have long-term capital appreciation potential and expect to grow faster than the U.S. economy. For purposes of the Portfolio, the portfolio managers will generally consider large-capitalization companies to be those that, at the time of purchase, have total market capitalizations within the range of market capitalizations of companies in the Russell 1000® Growth Index. While the market capitalization of companies in the Russell 1000 Growth Index ranged from approximately $717.61 million to approximately $583.6 billion as of Dec. 31, 2015, the Portfolio will normally invest in common stocks of companies with market capitalizations of at least $3 billion at the time of purchase. The market capitalization range for the Russell 1000 Growth Index will change on a periodic basis. A company's market capitalization is determined based on its current market capitalization. Russell Investment Group is the source and owner of the trademarks, service marks, and copyrights related to the Russell Indexes. Russell is a trademark of the Russell Investment Group.

Under normal circumstances, the Portfolio will invest at least 80% of its net assets, plus any borrowings for investment purposes, in equity securities of large-capitalization companies (80% Policy). The Portfolio's 80% Policy may be changed without shareholder approval. However, shareholders will be given notice at least 60 days prior to any such change.

Using a bottom-up approach, the portfolio managers seek to select securities of companies that have large market opportunities. Companies that have large market opportunities are those that, in our opinion, may have a large demand or market for their goods or services. The portfolio managers also consider a company's operational efficiencies, management's plans for capital allocation, and the company's shareholder orientation. All of these factors give the portfolio managers insight into the outlook for a company, helping the portfolio managers identify companies poised for sustainable free cash-flow growth. The portfolio managers believe that sustainable free cash-flow growth, if it occurs, may result in price appreciation for the company's stock.

Although the Portfolio tends to hold a relatively focused portfolio of between 25 and 40 stocks, it maintains a diversified portfolio representing a number of different industries. Such an approach helps to minimize the impact that any one security or industry could have on the portfolio if it were to experience a period of slow or declining earnings growth.

Because the Portfolio's objective is capital appreciation, the amount of dividend income that a stock provides is only an incidental consideration.

The Portfolio may also invest in other securities, including preferred stock, real estate investment trusts (REITs), warrants, equity and debt securities that are convertible into stocks, debt securities of government and corporate issuers and investment company securities, futures, and options. To the extent that this Portfolio invests in convertible debt securities, those securities will be purchased on the basis of their equity characteristics, and ratings of those securities, if any, will not be an important factor in their selection.

Strategy Portfolio Concentration rr_StrategyPortfolioConcentration
Under normal circumstances, the Portfolio will invest at least 80% of its net assets, plus any borrowings for investment purposes, in equity securities of large-capitalization companies (80% Policy). The Portfolio's 80% Policy may be changed without shareholder approval. However, shareholders will be given notice at least 60 days prior to any such change.
Risk, Heading rr_RiskHeading

What are the principal risks of investing in the Portfolio?

Risk, Narrative rr_RiskNarrativeTextBlock

Investing in any mutual fund involves the risk that you may lose part or all of the money you invest. Over time, the value of your investment in the Portfolio will increase and decrease according to changes in the value of the securities in its portfolio. Principal risks include:

Risk Definition

Market risk

The risk that all or a majority of the securities in a certain market — such as the stock or bond market — will decline in value because of factors such as adverse political or economic conditions, future expectations, investor confidence, or heavy institutional selling.

Foreign risk

The risk that foreign securities (particularly in emerging markets) may be adversely affected by political instability; changes in currency exchange rates; inefficient markets and higher transaction costs; foreign economic conditions; the imposition of economic or trade sanctions; or inadequate or different regulatory and accounting standards.

Real estate industry risk

This risk includes, among others, possible declines in the value of real estate; risks related to general and local economic conditions; possible lack of availability of mortgage funds; overbuilding; extended vacancies of properties; increases in competition, property taxes, and operating expenses; changes in zoning laws; costs resulting from the cleanup of, and liability to third parties resulting from, environmental problems; casualty for condemnation losses; uninsured damages from floods, earthquakes, or other natural disasters; limitations on and variations in rents; and changes in interest rates.

Futures and options risk

The possibility that a portfolio may experience a loss if it employs an options or futures strategy related to a security or a market index and that security or index moves in the opposite direction from what the manager anticipated. Futures and options also involve additional expenses, which could reduce any benefit or increase any loss that a portfolio gains from using the strategy.

Derivatives risk

Derivatives contracts, such as options, futures, and swaps, may involve additional expenses (such as the payment of premiums) and are subject to significant loss if a security or a securities index to which a derivatives contract is associated moves in the opposite direction from what the portfolio manager anticipated. Derivatives contracts are also subject to the risk that the counterparty may fail to perform its obligations under the contract due to financial difficulties (such as a bankruptcy or reorganization).

Credit risk

The risk that an issuer of a debt security, including a governmental issuer, or an entity that insures a bond may be unable to make interest payments and repay principal in a timely manner.

Liquidity risk

The possibility that securities cannot be readily sold within seven days at approximately the price at which a portfolio has valued them.

Investments not guaranteed by
Delaware Management Company
(Manager) or its affiliates

Neither the Manager nor its affiliates noted in this document are authorized deposit-taking institutions for the purposes of the Banking Act 1959 (Commonwealth of Australia). The obligations of these entities do not represent deposits or other liabilities of Macquarie Bank Limited (MBL). MBL does not guarantee or otherwise provide assurance in respect of the obligations of these entities, unless noted otherwise.

Risk, Lose Money rr_RiskLoseMoney
Investing in any mutual fund involves the risk that you may lose part or all of the money you invest.
Risk, Not Insured Depository Institution rr_RiskNotInsuredDepositoryInstitution
Neither the Manager nor its affiliates noted in this document are authorized deposit-taking institutions for the purposes of the Banking Act 1959 (Commonwealth of Australia). The obligations of these entities do not represent deposits or other liabilities of Macquarie Bank Limited (MBL). MBL does not guarantee or otherwise provide assurance in respect of the obligations of these entities, unless noted otherwise.
Bar Chart and Performance Table, Heading rr_BarChartAndPerformanceTableHeading

How has The Large-Cap Growth Equity Portfolio performed?

Performance, Narrative rr_PerformanceNarrativeTextBlock

The bar chart and table below provide some indication of the risks of investing in the Portfolio by showing changes in the Portfolio's performance from year to year and by showing how the Portfolio's average annual total returns for the 1-, 5-, and 10-year periods compare with those of a broad measure of market performance. The Portfolio's past performance (before and after taxes) is not necessarily an indication of how it will perform in the future. The returns reflect any expense caps in effect during these periods. The returns would be lower without the expense caps. You may obtain the Portfolio's most recently available month-end performance by calling 800 231-8002 or by visiting our website at delawareinvestments.com/institutional.

Performance, Information Illustrates Variability of Returns rr_PerformanceInformationIllustratesVariabilityOfReturns
The bar chart and table below provide some indication of the risks of investing in the Portfolio by showing changes in the Portfolio's performance from year to year and by showing how the Portfolio's average annual total returns for the 1-, 5-, and 10-year periods compare with those of a broad measure of market performance.
Performance Availability Phone rr_PerformanceAvailabilityPhone
800 231-8002
Performance Availability Website Address rr_PerformanceAvailabilityWebSiteAddress
delawareinvestments.com/institutional
Performance Past Does Not Indicate Future rr_PerformancePastDoesNotIndicateFuture
The Portfolio's past performance (before and after taxes) is not necessarily an indication of how it will perform in the future.
Bar Chart, Heading rr_BarChartHeading

Year-by-year total return (The Large-Cap Growth Equity Portfolio)

Bar Chart, Closing rr_BarChartClosingTextBlock

During the periods illustrated in this bar chart, The Large-Cap Growth Equity Portfolio's highest quarterly return was 16.08% for the quarter ended March 31, 2012 and its lowest quarterly return was -22.25% for the quarter ended Dec. 31, 2008.

Highest Quarterly Return, Label rr_HighestQuarterlyReturnLabel
highest quarterly return
Highest Quarterly Return, Date rr_BarChartHighestQuarterlyReturnDate Mar. 31, 2012
Highest Quarterly Return rr_BarChartHighestQuarterlyReturn 16.08%rr_BarChartHighestQuarterlyReturn
Lowest Quarterly Return, Label rr_LowestQuarterlyReturnLabel
lowest quarterly return
Lowest Quarterly Return, Date rr_BarChartLowestQuarterlyReturnDate Dec. 31, 2008
Lowest Quarterly Return rr_BarChartLowestQuarterlyReturn (22.25%)rr_BarChartLowestQuarterlyReturn
Performance Table, Heading rr_PerformanceTableHeading

Average annual total returns for periods ended December 31, 2015

Performance Table Uses Highest Federal Rate rr_PerformanceTableUsesHighestFederalRate
The after-tax returns shown are calculated using the highest individual federal marginal income tax rates in effect during the Portfolio's lifetime and do not reflect the impact of state and local taxes.
Performance Table Not Relevant to Tax Deferred rr_PerformanceTableNotRelevantToTaxDeferred
After-tax returns are not relevant for shares held in tax-deferred investment vehicles such as employer-sponsored 401(k) plans and individual retirement accounts (IRAs).
Performance Table, Closing rr_PerformanceTableClosingTextBlock

Russell Investment Group is the source and owner of the trademarks, service marks, and copyrights related to the Russell Indexes. Russell is a trademark of the Russell Investment Group.
Actual after-tax returns depend on the investor's individual tax situation and may differ from the returns shown. After-tax returns are not relevant for shares held in tax-deferred investment vehicles such as employer-sponsored 401(k) plans and individual retirement accounts (IRAs). The after-tax returns shown are calculated using the highest individual federal marginal income tax rates in effect during the Portfolio's lifetime and do not reflect the impact of state and local taxes.

Russell 1000® Growth Index
 
Risk/Return: rr_RiskReturnAbstract  
Index No Deduction for Fees, Expenses, Taxes rr_IndexNoDeductionForFeesExpensesTaxes
reflects no deduction for fees, expenses, or taxes
1 Year rr_AverageAnnualReturnYear01 5.67%rr_AverageAnnualReturnYear01
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DPT CLASS
 
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Annual Return 2008 rr_AnnualReturn2008 (43.22%)rr_AnnualReturn2008
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Annual Return 2010 rr_AnnualReturn2010 14.14%rr_AnnualReturn2010
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Annual Return 2014 rr_AnnualReturn2014 12.76%rr_AnnualReturn2014
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DPT CLASS | After Taxes on Distributions
 
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DPT CLASS | After Taxes on Distributions and sale of Portfolio shares
 
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[1] The Portfolio's investment manager, Delaware Management Company (Manager), has contractually agreed to waive all or a portion of its investment advisory fees and/or pay/reimburse expenses (excluding any 12b-1 fees, acquired fund fees and expenses, taxes, interest, expenses, short sale and dividend interest expenses, brokerage fees, certain insurance costs, and nonroutine expenses or costs, including, but not limited to, those relating to reorganizations, litigation, conducting shareholder meetings, and liquidations) in order to prevent total annual portfolio operating expenses from exceeding 0.65% of the Portfolio's average daily net assets from Feb. 26, 2016 through Feb. 28, 2017. The waivers and reimbursements may only be terminated by agreement of the Manager and the Portfolio.
v2.4.1.9
Equity Oriented or Fixed Income Oriented Funds | The Large-Cap Value Equity Portfolio

The Large-Cap Value Equity Portfolio

What is the Portfolio's investment objective?

The Large-Cap Value Equity Portfolio seeks long-term capital appreciation.

What are the Portfolio's fees and expenses?

The table below describes the fees and expenses that you may pay if you buy and hold shares of the Portfolio.

Annual portfolio operating expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses
Equity Oriented or Fixed Income Oriented Funds
The Large-Cap Value Equity Portfolio
DPT CLASS
Management fees 0.55%rr_ManagementFeesOverAssets
Distribution and service (12b-1) fees none
Other expenses 0.10%rr_OtherExpensesOverAssets
Total annual portfolio operating expenses 0.65%rr_ExpensesOverAssets
Fee waivers and expense reimbursements [1] none
Total annual portfolio operating expenses after fee waivers and expense reimbursements 0.65%rr_NetExpensesOverAssets
[1] The Portfolio's investment manager, Delaware Management Company (Manager), has contractually agreed to waive all or a portion of its investment advisory fees and/or pay/reimburse expenses (excluding any 12b-1 fees, acquired fund fees and expenses, taxes, interest, expenses, short sale and dividend interest expenses, brokerage fees, certain insurance costs, and nonroutine expenses or costs, including, but not limited to, those relating to reorganizations, litigation, conducting shareholder meetings, and liquidations) in order to prevent total annual portfolio operating expenses from exceeding 0.70% of the Portfolio's average daily net assets from Feb. 26, 2016 through Feb. 28, 2017. The waivers and reimbursements may only be terminated by agreement of the Manager and the Portfolio.

Example

This example is intended to help you compare the cost of investing in the Portfolio with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the Portfolio for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and reflects the Manager's expense waivers and reimbursements for the 1-year contractual period and the total operating expenses without waivers for years 2 through 10. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example (USD $)
1 Year
3 Years
5 Years
10 Years
Equity Oriented or Fixed Income Oriented Funds The Large-Cap Value Equity Portfolio DPT CLASS
66 208 362 810

Portfolio turnover

The Portfolio pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Portfolio shares are held in a taxable account. These costs, which are not reflected in annual portfolio operating expenses or in the example, affect the Portfolio's performance. During the most recent fiscal year, the Portfolio's portfolio turnover rate was 31% of the average value of its portfolio.

What are the Portfolio's principal investment strategies?

The Portfolio invests primarily in securities of large-capitalization companies that the Manager believes have long-term capital appreciation potential. The Portfolio currently defines large-capitalization stocks as those with market capitalizations of $5 billion or greater at the time of purchase. The Manager follows a value-oriented investment philosophy in selecting stocks for the Portfolio using a research-intensive approach that considers factors such as: security prices that reflect a market valuation that is judged to be below the estimated present or future value of the company; favorable earning prospects and dividend yield; the financial condition of the issuer; and various qualitative factors. Typically, the Manager seeks to select securities that it believes are undervalued in relation to their intrinsic value as indicated by multiple factors, including the earnings and cash-flow potential or the asset value of the respective issuers. The Manager also considers a company's plans for future operations on a selective basis.

Under normal circumstances, at least 80% of the Portfolio's net assets, plus any borrowings for investment purposes, will be invested in equity securities of large-capitalization companies (80% Policy). The Portfolio's 80% Policy may be changed without shareholder approval. However, shareholders will be given notice at least 60 days prior to any such change.

The Manager may sell a security if it no longer believes the security will contribute to meeting the investment objective of the Portfolio. In considering whether to sell a security, the Manager may evaluate, among other things, the factors listed above, the condition of the U.S. economy, the condition of non-U.S. economies, and changes in the condition and outlook in the issuer's industry sector.

What are the principal risks of investing in the Portfolio?

Investing in any mutual fund involves the risk that you may lose part or all of the money you invest. Over time, the value of your investment in the Portfolio will increase and decrease according to changes in the value of the securities in its portfolio. Principal risks include:

Risk Definition

Market risk

The risk that all or a majority of the securities in a certain market — such as the stock or bond market — will decline in value because of factors such as adverse political or economic conditions, future expectations, investor confidence, or heavy institutional selling.

Foreign risk

The risk that foreign securities (particularly in emerging markets) may be adversely affected by political instability; changes in currency exchange rates; inefficient markets and higher transaction costs; foreign economic conditions; the imposition of economic or trade sanctions; or inadequate or different regulatory and accounting standards.

Derivatives risk

Derivatives contracts, such as options, futures, and swaps, may involve additional expenses (such as the payment of premiums) and are subject to significant loss if a security or a securities index to which a derivatives contract is associated moves in the opposite direction from what the portfolio manager anticipated. Derivatives contracts are also subject to the risk that the counterparty may fail to perform its obligations under the contract due to financial difficulties (such as a bankruptcy or reorganization).

Liquidity risk

The possibility that securities cannot be readily sold within seven days at approximately the price at which a portfolio has valued them.

Investments not guaranteed by
Delaware Management Company
(Manager) or its affiliates

Neither the Manager nor its affiliates noted in this document are authorized deposit-taking institutions for the purposes of the Banking Act 1959 (Commonwealth of Australia). The obligations of these entities do not represent deposits or other liabilities of Macquarie Bank Limited (MBL). MBL does not guarantee or otherwise provide assurance in respect of the obligations of these entities, unless noted otherwise.

How has The Large-Cap Value Equity Portfolio performed?

The bar chart and table below provide some indication of the risks of investing in the Portfolio by showing changes in the Portfolio's performance from year to year and by showing how the Portfolio's average annual total returns for the 1-, 5-, and 10-year periods compare with those of a broad measure of market performance. The Portfolio's past performance (before and after taxes) is not necessarily an indication of how it will perform in the future. The returns reflect any expense caps in effect during these periods. The returns would be lower without the expense caps. You may obtain the Portfolio's most recently available month-end performance by calling 800 231-8002 or by visiting our website at delawareinvestments.com/institutional.

Year-by-year total return (The Large-Cap Value Equity Portfolio)

Bar Chart

During the periods illustrated in this bar chart, The Large-Cap Value Equity Portfolio's highest quarterly return was 14.29% for the quarter ended Dec. 31, 2011 and its lowest quarterly return was -13.21% for the quarter ended Dec. 31, 2008.

Average annual total returns for periods ended December 31, 2015

Average Annual Total Returns Equity Oriented or Fixed Income Oriented Funds The Large-Cap Value Equity Portfolio
1 Year
5 Years
10 Years
DPT CLASS
(0.74%) 13.97% 7.74%
DPT CLASS After Taxes on Distributions
(3.07%) 12.97% 6.91%
DPT CLASS After Taxes on Distributions and sale of Portfolio shares
1.44% 11.23% 6.28%
Russell 1000® Value Index
(3.83%) 11.27% 6.16%

Russell Investment Group is the source and owner of the trademarks, service marks, and copyrights related to the Russell Indexes. Russell is a trademark of the Russell Investment Group.
Actual after-tax returns depend on the investor's individual tax situation and may differ from the returns shown. After-tax returns are not relevant for shares held in tax-deferred investment vehicles such as employer-sponsored 401(k) plans and individual retirement accounts (IRAs). The after-tax returns shown are calculated using the highest individual federal marginal income tax rates in effect during the Portfolio's lifetime and do not reflect the impact of state and local taxes.

v2.4.1.9
Label Element Value
Risk/Return: rr_RiskReturnAbstract  
Risk/Return, Heading rr_RiskReturnHeading

The Large-Cap Value Equity Portfolio

Investment Objective, Heading rr_ObjectiveHeading

What is the Portfolio's investment objective?

Investment Objective, Primary rr_ObjectivePrimaryTextBlock

The Large-Cap Value Equity Portfolio seeks long-term capital appreciation.

Expense, Heading rr_ExpenseHeading

What are the Portfolio's fees and expenses?

Expense, Narrative rr_ExpenseNarrativeTextBlock

The table below describes the fees and expenses that you may pay if you buy and hold shares of the Portfolio.

Operating Expenses, Caption rr_OperatingExpensesCaption

Annual portfolio operating expenses (expenses that you pay each year as a percentage of the value of your investment)

Fee Waiver or Reimbursement over Assets, Date of Termination rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination
Feb. 28, 2017
Portfolio Turnover, Heading rr_PortfolioTurnoverHeading

Portfolio turnover

Portfolio Turnover rr_PortfolioTurnoverTextBlock

The Portfolio pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Portfolio shares are held in a taxable account. These costs, which are not reflected in annual portfolio operating expenses or in the example, affect the Portfolio's performance. During the most recent fiscal year, the Portfolio's portfolio turnover rate was 31% of the average value of its portfolio.

Portfolio Turnover, Rate rr_PortfolioTurnoverRate 31.00%rr_PortfolioTurnoverRate
Expense Example, Heading rr_ExpenseExampleHeading

Example

Expense Example, Narrative rr_ExpenseExampleNarrativeTextBlock

This example is intended to help you compare the cost of investing in the Portfolio with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the Portfolio for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and reflects the Manager's expense waivers and reimbursements for the 1-year contractual period and the total operating expenses without waivers for years 2 through 10. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Investment Strategy, Heading rr_StrategyHeading

What are the Portfolio's principal investment strategies?

Investment Strategy, Narrative rr_StrategyNarrativeTextBlock

The Portfolio invests primarily in securities of large-capitalization companies that the Manager believes have long-term capital appreciation potential. The Portfolio currently defines large-capitalization stocks as those with market capitalizations of $5 billion or greater at the time of purchase. The Manager follows a value-oriented investment philosophy in selecting stocks for the Portfolio using a research-intensive approach that considers factors such as: security prices that reflect a market valuation that is judged to be below the estimated present or future value of the company; favorable earning prospects and dividend yield; the financial condition of the issuer; and various qualitative factors. Typically, the Manager seeks to select securities that it believes are undervalued in relation to their intrinsic value as indicated by multiple factors, including the earnings and cash-flow potential or the asset value of the respective issuers. The Manager also considers a company's plans for future operations on a selective basis.

Under normal circumstances, at least 80% of the Portfolio's net assets, plus any borrowings for investment purposes, will be invested in equity securities of large-capitalization companies (80% Policy). The Portfolio's 80% Policy may be changed without shareholder approval. However, shareholders will be given notice at least 60 days prior to any such change.

The Manager may sell a security if it no longer believes the security will contribute to meeting the investment objective of the Portfolio. In considering whether to sell a security, the Manager may evaluate, among other things, the factors listed above, the condition of the U.S. economy, the condition of non-U.S. economies, and changes in the condition and outlook in the issuer's industry sector.

Strategy Portfolio Concentration rr_StrategyPortfolioConcentration
Under normal circumstances, at least 80% of the Portfolio's net assets, plus any borrowings for investment purposes, will be invested in equity securities of large-capitalization companies (80% Policy). The Portfolio's 80% Policy may be changed without shareholder approval. However, shareholders will be given notice at least 60 days prior to any such change.
Risk, Heading rr_RiskHeading

What are the principal risks of investing in the Portfolio?

Risk, Narrative rr_RiskNarrativeTextBlock

Investing in any mutual fund involves the risk that you may lose part or all of the money you invest. Over time, the value of your investment in the Portfolio will increase and decrease according to changes in the value of the securities in its portfolio. Principal risks include:

Risk Definition

Market risk

The risk that all or a majority of the securities in a certain market — such as the stock or bond market — will decline in value because of factors such as adverse political or economic conditions, future expectations, investor confidence, or heavy institutional selling.

Foreign risk

The risk that foreign securities (particularly in emerging markets) may be adversely affected by political instability; changes in currency exchange rates; inefficient markets and higher transaction costs; foreign economic conditions; the imposition of economic or trade sanctions; or inadequate or different regulatory and accounting standards.

Derivatives risk

Derivatives contracts, such as options, futures, and swaps, may involve additional expenses (such as the payment of premiums) and are subject to significant loss if a security or a securities index to which a derivatives contract is associated moves in the opposite direction from what the portfolio manager anticipated. Derivatives contracts are also subject to the risk that the counterparty may fail to perform its obligations under the contract due to financial difficulties (such as a bankruptcy or reorganization).

Liquidity risk

The possibility that securities cannot be readily sold within seven days at approximately the price at which a portfolio has valued them.

Investments not guaranteed by
Delaware Management Company
(Manager) or its affiliates

Neither the Manager nor its affiliates noted in this document are authorized deposit-taking institutions for the purposes of the Banking Act 1959 (Commonwealth of Australia). The obligations of these entities do not represent deposits or other liabilities of Macquarie Bank Limited (MBL). MBL does not guarantee or otherwise provide assurance in respect of the obligations of these entities, unless noted otherwise.

Risk, Lose Money rr_RiskLoseMoney
Investing in any mutual fund involves the risk that you may lose part or all of the money you invest.
Risk, Not Insured Depository Institution rr_RiskNotInsuredDepositoryInstitution
Neither the Manager nor its affiliates noted in this document are authorized deposit-taking institutions for the purposes of the Banking Act 1959 (Commonwealth of Australia). The obligations of these entities do not represent deposits or other liabilities of Macquarie Bank Limited (MBL). MBL does not guarantee or otherwise provide assurance in respect of the obligations of these entities, unless noted otherwise.
Bar Chart and Performance Table, Heading rr_BarChartAndPerformanceTableHeading

How has The Large-Cap Value Equity Portfolio performed?

Performance, Narrative rr_PerformanceNarrativeTextBlock

The bar chart and table below provide some indication of the risks of investing in the Portfolio by showing changes in the Portfolio's performance from year to year and by showing how the Portfolio's average annual total returns for the 1-, 5-, and 10-year periods compare with those of a broad measure of market performance. The Portfolio's past performance (before and after taxes) is not necessarily an indication of how it will perform in the future. The returns reflect any expense caps in effect during these periods. The returns would be lower without the expense caps. You may obtain the Portfolio's most recently available month-end performance by calling 800 231-8002 or by visiting our website at delawareinvestments.com/institutional.

Performance, Information Illustrates Variability of Returns rr_PerformanceInformationIllustratesVariabilityOfReturns
The bar chart and table below provide some indication of the risks of investing in the Portfolio by showing changes in the Portfolio's performance from year to year and by showing how the Portfolio's average annual total returns for the 1-, 5-, and 10-year periods compare with those of a broad measure of market performance.
Performance Availability Phone rr_PerformanceAvailabilityPhone
800 231-8002
Performance Availability Website Address rr_PerformanceAvailabilityWebSiteAddress
delawareinvestments.com/institutional
Performance Past Does Not Indicate Future rr_PerformancePastDoesNotIndicateFuture
The Portfolio's past performance (before and after taxes) is not necessarily an indication of how it will perform in the future.
Bar Chart, Heading rr_BarChartHeading

Year-by-year total return (The Large-Cap Value Equity Portfolio)

Bar Chart, Closing rr_BarChartClosingTextBlock

During the periods illustrated in this bar chart, The Large-Cap Value Equity Portfolio's highest quarterly return was 14.29% for the quarter ended Dec. 31, 2011 and its lowest quarterly return was -13.21% for the quarter ended Dec. 31, 2008.

Highest Quarterly Return, Label rr_HighestQuarterlyReturnLabel
highest quarterly return
Highest Quarterly Return, Date rr_BarChartHighestQuarterlyReturnDate Dec. 31, 2011
Highest Quarterly Return rr_BarChartHighestQuarterlyReturn 14.29%rr_BarChartHighestQuarterlyReturn
Lowest Quarterly Return, Label rr_LowestQuarterlyReturnLabel
lowest quarterly return
Lowest Quarterly Return, Date rr_BarChartLowestQuarterlyReturnDate Dec. 31, 2008
Lowest Quarterly Return rr_BarChartLowestQuarterlyReturn (13.21%)rr_BarChartLowestQuarterlyReturn
Performance Table, Heading rr_PerformanceTableHeading

Average annual total returns for periods ended December 31, 2015

Performance Table Uses Highest Federal Rate rr_PerformanceTableUsesHighestFederalRate
The after-tax returns shown are calculated using the highest individual federal marginal income tax rates in effect during the Portfolio's lifetime and do not reflect the impact of state and local taxes.
Performance Table Not Relevant to Tax Deferred rr_PerformanceTableNotRelevantToTaxDeferred
After-tax returns are not relevant for shares held in tax-deferred investment vehicles such as employer-sponsored 401(k) plans and individual retirement accounts (IRAs).
Performance Table, Closing rr_PerformanceTableClosingTextBlock

Russell Investment Group is the source and owner of the trademarks, service marks, and copyrights related to the Russell Indexes. Russell is a trademark of the Russell Investment Group.
Actual after-tax returns depend on the investor's individual tax situation and may differ from the returns shown. After-tax returns are not relevant for shares held in tax-deferred investment vehicles such as employer-sponsored 401(k) plans and individual retirement accounts (IRAs). The after-tax returns shown are calculated using the highest individual federal marginal income tax rates in effect during the Portfolio's lifetime and do not reflect the impact of state and local taxes.

Russell 1000® Value Index
 
Risk/Return: rr_RiskReturnAbstract  
Index No Deduction for Fees, Expenses, Taxes rr_IndexNoDeductionForFeesExpensesTaxes
reflects no deduction for fees, expenses, or taxes
1 Year rr_AverageAnnualReturnYear01 (3.83%)rr_AverageAnnualReturnYear01
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DPT CLASS
 
Risk/Return: rr_RiskReturnAbstract  
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DPT CLASS | After Taxes on Distributions
 
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DPT CLASS | After Taxes on Distributions and sale of Portfolio shares
 
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10 Years rr_AverageAnnualReturnYear10 6.28%rr_AverageAnnualReturnYear10
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[1] The Portfolio's investment manager, Delaware Management Company (Manager), has contractually agreed to waive all or a portion of its investment advisory fees and/or pay/reimburse expenses (excluding any 12b-1 fees, acquired fund fees and expenses, taxes, interest, expenses, short sale and dividend interest expenses, brokerage fees, certain insurance costs, and nonroutine expenses or costs, including, but not limited to, those relating to reorganizations, litigation, conducting shareholder meetings, and liquidations) in order to prevent total annual portfolio operating expenses from exceeding 0.70% of the Portfolio's average daily net assets from Feb. 26, 2016 through Feb. 28, 2017. The waivers and reimbursements may only be terminated by agreement of the Manager and the Portfolio.
v2.4.1.9
Equity Oriented or Fixed Income Oriented Funds | The Focus Smid-Cap Growth Equity Portfolio

The Focus Smid-Cap Growth Equity Portfolio

What is the Portfolio's investment objective?

The Focus Smid-Cap Growth Equity Portfolio seeks long-term capital appreciation.

What are the Portfolio's fees and expenses?

The table below describes the fees and expenses that you may pay if you buy and hold shares of the Portfolio.

Annual portfolio operating expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses
Equity Oriented or Fixed Income Oriented Funds
The Focus Smid-Cap Growth Equity Portfolio
DPT CLASS
Management fees 0.75%rr_ManagementFeesOverAssets
Distribution and service (12b-1) fees none
Other expenses 0.17%rr_OtherExpensesOverAssets
Total annual portfolio operating expenses 0.92%rr_ExpensesOverAssets
Fee waivers and expense reimbursements [1] none
Total annual portfolio operating expenses after fee waivers and expense reimbursements 0.92%rr_NetExpensesOverAssets
[1] The Portfolio's investment manager, Delaware Management Company (Manager), has contractually agreed to waive all or a portion of its investment advisory fees and/or pay/ reimburse expenses (excluding any 12b-1 fees, acquired fund fees and expenses, taxes, interest, expenses, short sale and dividend interest expenses, brokerage fees, certain insurance costs, and nonroutine expenses or costs, including, but not limited to, those relating to reorganizations, litigation, conducting shareholder meetings, and liquidations) in order to prevent total annual portfolio operating expenses from exceeding 0.92% of the Portfolio's average daily net assets from Feb. 26, 2016 through Feb. 28, 2017. The waivers and reimbursements may only be terminated by agreement of the Manager and the Portfolio.

Example

This example is intended to help you compare the cost of investing in the Portfolio with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the Portfolio for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and reflects the Manager's expense waivers and reimbursements for the 1-year contractual period and the total operating expenses without waivers for years 2 through 10. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example (USD $)
1 Year
3 Years
5 Years
10 Years
Equity Oriented or Fixed Income Oriented Funds The Focus Smid-Cap Growth Equity Portfolio DPT CLASS
94 293 509 1,131

Portfolio turnover

The Portfolio pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Portfolio shares are held in a taxable account. These costs, which are not reflected in annual portfolio operating expenses or in the example, affect the Portfolio's performance. During the most recent fiscal year, the Portfolio's portfolio turnover rate was 21% of the average value of its portfolio.

What are the Portfolio's principal investment strategies?

The Portfolio invests primarily in common stocks of growth-oriented companies that its portfolio managers believe have long-term capital appreciation potential and expect to grow faster than the U.S. economy. Under normal circumstances, the Portfolio invests at least 80% of its net assets, plus any borrowings for investment purposes, in securities of small- and mid-capitalization companies (80% policy). The Portfolio's 80% policy may be changed without shareholder approval. However, shareholders will be given notice at least 60 days prior to any such change. For purposes of this Portfolio, small-market capitalization companies are those companies whose market capitalization is similar to the market capitalization of companies in the Russell 2000® Growth Index, and mid-market capitalization companies are those companies whose market capitalization is similar to the market capitalization of companies in the Russell Midcap® Growth Index. The two indices listed above are for purposes of determining range and not for targeting portfolio management. As of Dec. 31, 2015, the Russell 2000 Growth Index had a market capitalization range between $18.66 million and $6.5 billion, and the Russell Midcap Growth Index had a market capitalization range between $717.6 million and $30.5 billion. The market capitalization ranges for the Russell 2000 Growth Index and Russell Midcap Growth Index will change on a periodic basis. A company's market capitalization is determined based on its current market capitalization. Russell Investment Group is the source and owner of the trademarks, service marks, and copyrights related to the Russell Indexes. Russell is a trademark of the Russell Investment Group.

Under normal circumstances, the Portfolio will invest at least 80% of its net assets, plus any borrowings for investment purposes, in equity securities of small and mid-capitalization companies (80% Policy). The Portfolio's 80% Policy may be changed without shareholder approval. However, shareholders will be given notice at least 60 days prior to any such change.

Using a bottom-up approach, the portfolio managers seek to select securities of companies that have large market opportunities. Companies that have large market opportunities are those that, in the portfolio managers' opinion, may have a large demand or market for their goods or services. The portfolio managers also consider a company's operational efficiencies, management's plans for capital allocation, and the company's shareholder orientation. All of these factors give the portfolio managers insight into the outlook for a company, helping the portfolio managers identify companies poised for sustainable free cash-flow growth. The portfolio managers believe that sustainable free cash-flow growth, if it occurs, may result in price appreciation for the company's stock.

The Portfolio generally holds 25 to 30 stocks, although from time to time the Portfolio may hold fewer or more names depending on our assessment of the investment opportunities available. In addition, the portfolio managers maintain a diversified portfolio representing a number of different industries. Such an approach helps to minimize the impact that any one security or industry could have on the Portfolio if the security or industry were to experience a period of slow or declining growth.

Because the Portfolio's objective is capital appreciation, the amount of dividend income that a stock provides is only an incidental consideration.

The Portfolio may engage in options and futures transactions. In addition, the Portfolio may invest up to 20% of its assets in foreign securities, which may include global depositary receipts (GDRs) and, without limitation, in sponsored and unsponsored American depositary receipts (ADRs) that are actively traded in the United States. The Portfolio may invest up to 10% of its net assets in emerging market securities.

The Portfolio may invest in real estate investment trusts (REITs).

In unusual market conditions, in order to meet redemption requests, for temporary defensive purposes and pending investment, the Portfolio may hold a substantial portion of its assets in cash or short-term, debt obligations.

What are the principal risks of investing in the Portfolio?

Investing in any mutual fund involves the risk that you may lose part or all of the money you invest. Over time, the value of your investment in the Portfolio will increase and decrease according to changes in the value of the securities in its portfolio. Principal risks include:

Risk Definition

Market risk

The risk that all or a majority of the securities in a certain market — such as the stock or bond market — will decline in value because of factors such as adverse political or economic conditions, future expectations, investor confidence, or heavy institutional selling.

Limited number of stocks risk

The possibility that a single security's increase or decrease in value may have a greater impact on the fund's value and total return because the fund may hold larger positions in fewer securities than other funds.

Company size risk

The risk that investments in small- and/or medium-sized companies may be more volatile than those of larger companies because of limited financial resources or dependence on narrow product lines.

Foreign risk

The risk that foreign securities (particularly in emerging markets) may be adversely affected by political instability; changes in currency exchange rates; inefficient markets and higher transaction costs; foreign economic conditions; the imposition of economic or trade sanctions; or inadequate or different regulatory and accounting standards.

Currency risk

The risk that the value of a portfolio's investments may be negatively affected by changes in foreign currency exchange rates.

Real estate industry risk

This risk includes, among others, possible declines in the value of real estate; risks related to general and local economic conditions; possible lack of availability of mortgage funds; overbuilding; extended vacancies of properties; increases in competition, property taxes, and operating expenses; changes in zoning laws; costs resulting from the cleanup of, and liability to third parties resulting from, environmental problems; casualty for condemnation losses; uninsured damages from floods, earthquakes, or other natural disasters; limitations on and variations in rents; and changes in interest rates.

Derivatives risk

Derivatives contracts, such as options, futures, and swaps, may involve additional expenses (such as the payment of premiums) and are subject to significant loss if a security or a securities index to which a derivatives contract is associated moves in the opposite direction from what the portfolio manager anticipated. Derivatives contracts are also subject to the risk that the counterparty may fail to perform its obligations under the contract due to financial difficulties (such as a bankruptcy or reorganization).

Counterparty risk

The risk that a counterparty to a derivatives contract (such as a futures or options contract) or a repurchase agreement may fail to perform its obligations under the contract or agreement due to financial difficulties (such as a bankruptcy or reorganization).

Credit risk

The risk that an issuer of a debt security, including a governmental issuer, or an entity that insures a bond may be unable to make interest payments and repay principal in a timely manner.

Interest rate risk

The risk that securities will decrease in value if interest rates rise. The risk is generally associated with bonds; however, because companies in the real estate sector and smaller companies often borrow money to finance their operations, they may be adversely affected by rising interest rates.

Liquidity risk

The possibility that securities cannot be readily sold within seven days at approximately the price at which a portfolio has valued them.

Investments not guaranteed by
Delaware Management Company
(Manager) or its affiliates

Neither the Manager nor its affiliates noted in this document are authorized deposit-taking institutions for the purposes of the Banking Act 1959 (Commonwealth of Australia). The obligations of these entities do not represent deposits or other liabilities of  Macquarie Bank Limited (MBL). MBL does not guarantee or otherwise provide assurance in respect of the obligations of these entities, unless noted otherwise.

How has The Focus Smid-Cap Growth Equity Portfolio performed?

The bar chart and table below provide some indication of the risks of investing in the Portfolio by showing changes in the Portfolio's performance from year to year and by showing how the Portfolio's average annual total returns for the 1-, 5-, and 10-year periods compare with those of a broad measure of market performance. The Portfolio's past performance (before and after taxes) is not necessarily an indication of how it will perform in the future. The returns reflect any expense caps in effect during these periods. The returns would be lower without the expense caps. You may obtain the Portfolio's most recently available month-end performance by calling 800 231-8002 or by visiting our website at delawareinvestments.com/institutional.

Year-by-year total return (The Focus Smid-Cap Growth Equity Portfolio)

Bar Chart

During the periods illustrated in this bar chart, The Focus Smid-Cap Growth Equity Portfolio's highest quarterly return was 27.04% for the quarter ended June 30, 2009 and its lowest quarterly return was -24.94% for the quarter ended Dec. 31, 2008.

Average annual total returns for periods ended December 31, 2015

Average Annual Total Returns Equity Oriented or Fixed Income Oriented Funds The Focus Smid-Cap Growth Equity Portfolio
1 Year
5 Years
10 Years
DPT CLASS
7.40% 12.99% 11.48%
DPT CLASS After Taxes on Distributions
5.89% 11.16% 10.24%
DPT CLASS After Taxes on Distributions and sale of Portfolio shares
5.41% 10.09% 9.24%
Russell 2500® Growth Index
(0.19%) 11.43% 8.49%

Russell Investment Group is the source and owner of the trademarks, service marks, and copyrights related to the Russell Indexes. Russell is a trademark of the Russell Investment Group.
Actual after-tax returns depend on the investor's individual tax situation and may differ from the returns shown. After-tax returns are not relevant for shares held in tax-deferred investment vehicles such as employer-sponsored 401(k) plans and individual retirement accounts (IRAs). The after-tax returns shown are calculated using the highest individual federal marginal income tax rates in effect during the Portfolio's lifetime and do not reflect the impact of state and local taxes.

v2.4.1.9
Label Element Value
Risk/Return: rr_RiskReturnAbstract  
Risk/Return, Heading rr_RiskReturnHeading

The Focus Smid-Cap Growth Equity Portfolio

Investment Objective, Heading rr_ObjectiveHeading

What is the Portfolio's investment objective?

Investment Objective, Primary rr_ObjectivePrimaryTextBlock

The Focus Smid-Cap Growth Equity Portfolio seeks long-term capital appreciation.

Expense, Heading rr_ExpenseHeading

What are the Portfolio's fees and expenses?

Expense, Narrative rr_ExpenseNarrativeTextBlock

The table below describes the fees and expenses that you may pay if you buy and hold shares of the Portfolio.

Operating Expenses, Caption rr_OperatingExpensesCaption

Annual portfolio operating expenses (expenses that you pay each year as a percentage of the value of your investment)

Fee Waiver or Reimbursement over Assets, Date of Termination rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination
Feb. 28, 2017
Portfolio Turnover, Heading rr_PortfolioTurnoverHeading

Portfolio turnover

Portfolio Turnover rr_PortfolioTurnoverTextBlock

The Portfolio pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Portfolio shares are held in a taxable account. These costs, which are not reflected in annual portfolio operating expenses or in the example, affect the Portfolio's performance. During the most recent fiscal year, the Portfolio's portfolio turnover rate was 21% of the average value of its portfolio.

Portfolio Turnover, Rate rr_PortfolioTurnoverRate 21.00%rr_PortfolioTurnoverRate
Expense Example, Heading rr_ExpenseExampleHeading

Example

Expense Example, Narrative rr_ExpenseExampleNarrativeTextBlock

This example is intended to help you compare the cost of investing in the Portfolio with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the Portfolio for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and reflects the Manager's expense waivers and reimbursements for the 1-year contractual period and the total operating expenses without waivers for years 2 through 10. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Investment Strategy, Heading rr_StrategyHeading

What are the Portfolio's principal investment strategies?

Investment Strategy, Narrative rr_StrategyNarrativeTextBlock

The Portfolio invests primarily in common stocks of growth-oriented companies that its portfolio managers believe have long-term capital appreciation potential and expect to grow faster than the U.S. economy. Under normal circumstances, the Portfolio invests at least 80% of its net assets, plus any borrowings for investment purposes, in securities of small- and mid-capitalization companies (80% policy). The Portfolio's 80% policy may be changed without shareholder approval. However, shareholders will be given notice at least 60 days prior to any such change. For purposes of this Portfolio, small-market capitalization companies are those companies whose market capitalization is similar to the market capitalization of companies in the Russell 2000® Growth Index, and mid-market capitalization companies are those companies whose market capitalization is similar to the market capitalization of companies in the Russell Midcap® Growth Index. The two indices listed above are for purposes of determining range and not for targeting portfolio management. As of Dec. 31, 2015, the Russell 2000 Growth Index had a market capitalization range between $18.66 million and $6.5 billion, and the Russell Midcap Growth Index had a market capitalization range between $717.6 million and $30.5 billion. The market capitalization ranges for the Russell 2000 Growth Index and Russell Midcap Growth Index will change on a periodic basis. A company's market capitalization is determined based on its current market capitalization. Russell Investment Group is the source and owner of the trademarks, service marks, and copyrights related to the Russell Indexes. Russell is a trademark of the Russell Investment Group.

Under normal circumstances, the Portfolio will invest at least 80% of its net assets, plus any borrowings for investment purposes, in equity securities of small and mid-capitalization companies (80% Policy). The Portfolio's 80% Policy may be changed without shareholder approval. However, shareholders will be given notice at least 60 days prior to any such change.

Using a bottom-up approach, the portfolio managers seek to select securities of companies that have large market opportunities. Companies that have large market opportunities are those that, in the portfolio managers' opinion, may have a large demand or market for their goods or services. The portfolio managers also consider a company's operational efficiencies, management's plans for capital allocation, and the company's shareholder orientation. All of these factors give the portfolio managers insight into the outlook for a company, helping the portfolio managers identify companies poised for sustainable free cash-flow growth. The portfolio managers believe that sustainable free cash-flow growth, if it occurs, may result in price appreciation for the company's stock.

The Portfolio generally holds 25 to 30 stocks, although from time to time the Portfolio may hold fewer or more names depending on our assessment of the investment opportunities available. In addition, the portfolio managers maintain a diversified portfolio representing a number of different industries. Such an approach helps to minimize the impact that any one security or industry could have on the Portfolio if the security or industry were to experience a period of slow or declining growth.

Because the Portfolio's objective is capital appreciation, the amount of dividend income that a stock provides is only an incidental consideration.

The Portfolio may engage in options and futures transactions. In addition, the Portfolio may invest up to 20% of its assets in foreign securities, which may include global depositary receipts (GDRs) and, without limitation, in sponsored and unsponsored American depositary receipts (ADRs) that are actively traded in the United States. The Portfolio may invest up to 10% of its net assets in emerging market securities.

The Portfolio may invest in real estate investment trusts (REITs).

In unusual market conditions, in order to meet redemption requests, for temporary defensive purposes and pending investment, the Portfolio may hold a substantial portion of its assets in cash or short-term, debt obligations.

Strategy Portfolio Concentration rr_StrategyPortfolioConcentration
Under normal circumstances, the Portfolio will invest at least 80% of its net assets, plus any borrowings for investment purposes, in equity securities of small and mid-capitalization companies (80% Policy). The Portfolio's 80% Policy may be changed without shareholder approval. However, shareholders will be given notice at least 60 days prior to any such change.
Risk, Heading rr_RiskHeading

What are the principal risks of investing in the Portfolio?

Risk, Narrative rr_RiskNarrativeTextBlock

Investing in any mutual fund involves the risk that you may lose part or all of the money you invest. Over time, the value of your investment in the Portfolio will increase and decrease according to changes in the value of the securities in its portfolio. Principal risks include:

Risk Definition

Market risk

The risk that all or a majority of the securities in a certain market — such as the stock or bond market — will decline in value because of factors such as adverse political or economic conditions, future expectations, investor confidence, or heavy institutional selling.

Limited number of stocks risk

The possibility that a single security's increase or decrease in value may have a greater impact on the fund's value and total return because the fund may hold larger positions in fewer securities than other funds.

Company size risk

The risk that investments in small- and/or medium-sized companies may be more volatile than those of larger companies because of limited financial resources or dependence on narrow product lines.

Foreign risk

The risk that foreign securities (particularly in emerging markets) may be adversely affected by political instability; changes in currency exchange rates; inefficient markets and higher transaction costs; foreign economic conditions; the imposition of economic or trade sanctions; or inadequate or different regulatory and accounting standards.

Currency risk

The risk that the value of a portfolio's investments may be negatively affected by changes in foreign currency exchange rates.

Real estate industry risk

This risk includes, among others, possible declines in the value of real estate; risks related to general and local economic conditions; possible lack of availability of mortgage funds; overbuilding; extended vacancies of properties; increases in competition, property taxes, and operating expenses; changes in zoning laws; costs resulting from the cleanup of, and liability to third parties resulting from, environmental problems; casualty for condemnation losses; uninsured damages from floods, earthquakes, or other natural disasters; limitations on and variations in rents; and changes in interest rates.

Derivatives risk

Derivatives contracts, such as options, futures, and swaps, may involve additional expenses (such as the payment of premiums) and are subject to significant loss if a security or a securities index to which a derivatives contract is associated moves in the opposite direction from what the portfolio manager anticipated. Derivatives contracts are also subject to the risk that the counterparty may fail to perform its obligations under the contract due to financial difficulties (such as a bankruptcy or reorganization).

Counterparty risk

The risk that a counterparty to a derivatives contract (such as a futures or options contract) or a repurchase agreement may fail to perform its obligations under the contract or agreement due to financial difficulties (such as a bankruptcy or reorganization).

Credit risk

The risk that an issuer of a debt security, including a governmental issuer, or an entity that insures a bond may be unable to make interest payments and repay principal in a timely manner.

Interest rate risk

The risk that securities will decrease in value if interest rates rise. The risk is generally associated with bonds; however, because companies in the real estate sector and smaller companies often borrow money to finance their operations, they may be adversely affected by rising interest rates.

Liquidity risk

The possibility that securities cannot be readily sold within seven days at approximately the price at which a portfolio has valued them.

Investments not guaranteed by
Delaware Management Company
(Manager) or its affiliates

Neither the Manager nor its affiliates noted in this document are authorized deposit-taking institutions for the purposes of the Banking Act 1959 (Commonwealth of Australia). The obligations of these entities do not represent deposits or other liabilities of  Macquarie Bank Limited (MBL). MBL does not guarantee or otherwise provide assurance in respect of the obligations of these entities, unless noted otherwise.

Risk, Lose Money rr_RiskLoseMoney
Investing in any mutual fund involves the risk that you may lose part or all of the money you invest.
Risk, Not Insured Depository Institution rr_RiskNotInsuredDepositoryInstitution
Neither the Manager nor its affiliates noted in this document are authorized deposit-taking institutions for the purposes of the Banking Act 1959 (Commonwealth of Australia). The obligations of these entities do not represent deposits or other liabilities of  Macquarie Bank Limited (MBL). MBL does not guarantee or otherwise provide assurance in respect of the obligations of these entities, unless noted otherwise.
Bar Chart and Performance Table, Heading rr_BarChartAndPerformanceTableHeading

How has The Focus Smid-Cap Growth Equity Portfolio performed?

Performance, Narrative rr_PerformanceNarrativeTextBlock

The bar chart and table below provide some indication of the risks of investing in the Portfolio by showing changes in the Portfolio's performance from year to year and by showing how the Portfolio's average annual total returns for the 1-, 5-, and 10-year periods compare with those of a broad measure of market performance. The Portfolio's past performance (before and after taxes) is not necessarily an indication of how it will perform in the future. The returns reflect any expense caps in effect during these periods. The returns would be lower without the expense caps. You may obtain the Portfolio's most recently available month-end performance by calling 800 231-8002 or by visiting our website at delawareinvestments.com/institutional.

Performance, Information Illustrates Variability of Returns rr_PerformanceInformationIllustratesVariabilityOfReturns
The bar chart and table below provide some indication of the risks of investing in the Portfolio by showing changes in the Portfolio's performance from year to year and by showing how the Portfolio's average annual total returns for the 1-, 5-, and 10-year periods compare with those of a broad measure of market performance.
Performance Availability Phone rr_PerformanceAvailabilityPhone
800 231-8002
Performance Availability Website Address rr_PerformanceAvailabilityWebSiteAddress
delawareinvestments.com/institutional
Performance Past Does Not Indicate Future rr_PerformancePastDoesNotIndicateFuture
The Portfolio's past performance (before and after taxes) is not necessarily an indication of how it will perform in the future.
Bar Chart, Heading rr_BarChartHeading

Year-by-year total return (The Focus Smid-Cap Growth Equity Portfolio)

Bar Chart, Closing rr_BarChartClosingTextBlock

During the periods illustrated in this bar chart, The Focus Smid-Cap Growth Equity Portfolio's highest quarterly return was 27.04% for the quarter ended June 30, 2009 and its lowest quarterly return was -24.94% for the quarter ended Dec. 31, 2008.

Highest Quarterly Return, Label rr_HighestQuarterlyReturnLabel
highest quarterly return
Highest Quarterly Return, Date rr_BarChartHighestQuarterlyReturnDate Jun. 30, 2009
Highest Quarterly Return rr_BarChartHighestQuarterlyReturn 27.04%rr_BarChartHighestQuarterlyReturn
Lowest Quarterly Return, Label rr_LowestQuarterlyReturnLabel
lowest quarterly return
Lowest Quarterly Return, Date rr_BarChartLowestQuarterlyReturnDate Dec. 31, 2008
Lowest Quarterly Return rr_BarChartLowestQuarterlyReturn (24.94%)rr_BarChartLowestQuarterlyReturn
Performance Table, Heading rr_PerformanceTableHeading

Average annual total returns for periods ended December 31, 2015

Performance Table Uses Highest Federal Rate rr_PerformanceTableUsesHighestFederalRate
The after-tax returns shown are calculated using the highest individual federal marginal income tax rates in effect during the Portfolio's lifetime and do not reflect the impact of state and local taxes.
Performance Table Not Relevant to Tax Deferred rr_PerformanceTableNotRelevantToTaxDeferred
After-tax returns are not relevant for shares held in tax-deferred investment vehicles such as employer-sponsored 401(k) plans and individual retirement accounts (IRAs).
Performance Table, Closing rr_PerformanceTableClosingTextBlock

Russell Investment Group is the source and owner of the trademarks, service marks, and copyrights related to the Russell Indexes. Russell is a trademark of the Russell Investment Group.
Actual after-tax returns depend on the investor's individual tax situation and may differ from the returns shown. After-tax returns are not relevant for shares held in tax-deferred investment vehicles such as employer-sponsored 401(k) plans and individual retirement accounts (IRAs). The after-tax returns shown are calculated using the highest individual federal marginal income tax rates in effect during the Portfolio's lifetime and do not reflect the impact of state and local taxes.

Russell 2500® Growth Index
 
Risk/Return: rr_RiskReturnAbstract  
Index No Deduction for Fees, Expenses, Taxes rr_IndexNoDeductionForFeesExpensesTaxes
reflects no deduction for fees, expenses, or taxes
1 Year rr_AverageAnnualReturnYear01 (0.19%)rr_AverageAnnualReturnYear01
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5 Years rr_AverageAnnualReturnYear05 11.43%rr_AverageAnnualReturnYear05
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10 Years rr_AverageAnnualReturnYear10 8.49%rr_AverageAnnualReturnYear10
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DPT CLASS
 
Risk/Return: rr_RiskReturnAbstract  
Management fees rr_ManagementFeesOverAssets 0.75%rr_ManagementFeesOverAssets
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Distribution and service (12b-1) fees rr_DistributionAndService12b1FeesOverAssets none
Other expenses rr_OtherExpensesOverAssets 0.17%rr_OtherExpensesOverAssets
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Total annual portfolio operating expenses rr_ExpensesOverAssets 0.92%rr_ExpensesOverAssets
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Fee waivers and expense reimbursements rr_FeeWaiverOrReimbursementOverAssets none [1]
Total annual portfolio operating expenses after fee waivers and expense reimbursements rr_NetExpensesOverAssets 0.92%rr_NetExpensesOverAssets
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1 Year rr_ExpenseExampleYear01 94rr_ExpenseExampleYear01
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3 Years rr_ExpenseExampleYear03 293rr_ExpenseExampleYear03
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5 Years rr_ExpenseExampleYear05 509rr_ExpenseExampleYear05
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10 Years rr_ExpenseExampleYear10 1,131rr_ExpenseExampleYear10
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Annual Return 2006 rr_AnnualReturn2006 5.41%rr_AnnualReturn2006
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Annual Return 2007 rr_AnnualReturn2007 7.19%rr_AnnualReturn2007
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Annual Return 2008 rr_AnnualReturn2008 (35.91%)rr_AnnualReturn2008
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Annual Return 2009 rr_AnnualReturn2009 55.76%rr_AnnualReturn2009
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Annual Return 2012 rr_AnnualReturn2012 10.65%rr_AnnualReturn2012
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DPT CLASS | After Taxes on Distributions
 
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[1] The Portfolio's investment manager, Delaware Management Company (Manager), has contractually agreed to waive all or a portion of its investment advisory fees and/or pay/ reimburse expenses (excluding any 12b-1 fees, acquired fund fees and expenses, taxes, interest, expenses, short sale and dividend interest expenses, brokerage fees, certain insurance costs, and nonroutine expenses or costs, including, but not limited to, those relating to reorganizations, litigation, conducting shareholder meetings, and liquidations) in order to prevent total annual portfolio operating expenses from exceeding 0.92% of the Portfolio's average daily net assets from Feb. 26, 2016 through Feb. 28, 2017. The waivers and reimbursements may only be terminated by agreement of the Manager and the Portfolio.
v2.4.1.9
Equity Oriented or Fixed Income Oriented Funds | The Select 20 Portfolio

The Select 20 Portfolio

What is the Portfolio's investment objective?

The Select 20 Portfolio seeks long-term capital appreciation.

What are the Portfolio's fees and expenses?

The table below describes the fees and expenses that you may pay if you buy and hold shares of the Portfolio.

Annual portfolio operating expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses
Equity Oriented or Fixed Income Oriented Funds
The Select 20 Portfolio
DPT CLASS
Management fees 0.75%rr_ManagementFeesOverAssets
Distribution and service (12b-1) fees none
Other expenses 0.14%rr_OtherExpensesOverAssets
Total annual portfolio operating expenses 0.89%rr_ExpensesOverAssets
Less fee waivers and expense reimbursements [1] none
Total annual portfolio operating expenses after fee waivers and expense reimbursements 0.89%rr_NetExpensesOverAssets
[1] The Portfolio's investment manager, Delaware Management Company (Manager), has contractually agreed to waive all or a portion of its investment advisory fees and/or pay/ reimburse expenses (excluding any 12b-1 fees, acquired fund fees and expenses, taxes, interest, expenses, short sale and dividend interest expenses, brokerage fees, certain insurance costs, and nonroutine expenses or costs, including, but not limited to, those relating to reorganizations, litigation, conducting shareholder meetings, and liquidations) in order to prevent total annual portfolio operating expenses from exceeding 0.89% of the Portfolio's average daily net assets from Feb. 26, 2016 through Feb. 28, 2017. These waivers and reimbursements may only be terminated by agreement of the Manager and the Portfolio.

Example

This example is intended to help you compare the cost of investing in the Portfolio with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the Portfolio for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and reflects the Manager's expense waivers and reimbursements for the 1-year contractual period and the total operating expenses without waivers for years 2 through 10. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example (USD $)
1 Year
3 Years
5 Years
10 Years
Equity Oriented or Fixed Income Oriented Funds The Select 20 Portfolio DPT CLASS
91 284 493 1,096

Portfolio turnover

The Portfolio pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Portfolio shares are held in a taxable account. These costs, which are not reflected in annual portfolio operating expenses or in the example, affect the Portfolio's performance. During the most recent fiscal year, the Portfolio's portfolio turnover rate was 31% of the average value of its portfolio.

What are the Portfolio's principal investment strategies?

The Portfolio seeks to achieve its objective by investing in a portfolio of 20 securities. The Portfolio will invest in no fewer than 15 and no more than 25 equity securities. The Portfolio is considered “nondiversified” as defined in the Investment Company Act of 1940, as amended (1940 Act), which means that it may invest in a smaller number of issuers than a diversified mutual fund.

The portfolio managers invest primarily in common stocks of companies that they believe have long-term capital appreciation potential and are expected to grow faster than the U.S. economy. The portfolio managers consider companies of any size or market capitalization. Using a bottom-up approach, the portfolio managers seek to select securities of companies that have large market opportunities. Companies that have large market opportunities are those that, in the portfolio managers' opinion, may have a large demand or market for their goods or services. The portfolio managers also consider a company's operational efficiencies, management plans for capital allocation, and the company's shareholder orientation.

The portfolio managers research individual companies and analyze economic and market conditions, seeking to identify the securities or market sectors that they think are the best investments for the Portfolio. Specifically, the portfolio managers look for structural changes in the economy, industry, or product cycle changes, or changes in management, targeting those companies that can best capitalize on such changes. The following is a description of how the portfolio managers pursue the Portfolio's investment goals.

The portfolio managers strive to identify companies that offer the potential for long-term price appreciation because they are likely to experience sustainable free cash-flow growth. Using a bottom-up approach, the portfolio managers look for companies that they believe:

have attractive end-market potential or dominance of a profitable niche market, dominant business models, and strong cash-flow generation;
 

demonstrate operational and scale efficiencies;
 

have demonstrated expertise for capital allocation; or
 

have clear shareholder-oriented governance and compensation policies.

All of these factors give the portfolio managers insight into the outlook for a company, helping the portfolio managers to identify companies poised for sustainable free cash-flow growth. The portfolio managers believe that sustainable free cash-flow growth, if it occurs, may result in price appreciation for the company's stock.

The portfolio managers maintain a diversified portfolio, typically holding a mix of different stocks, representing a wide array of industries and a mix of small-, medium-, and large-size companies.

The portfolio managers may invest up to 20% of the Portfolio's net assets in securities of foreign issuers, including issuers located in emerging markets.

The portfolio managers may invest in real estate investment trusts (REITs).

What are the principal risks of investing in the Portfolio?

Investing in any mutual fund involves the risk that you may lose part or all of the money you invest. Over time, the value of your investment in the Portfolio will increase and decrease according to changes in the value of the securities in its portfolio. Principal risks include:

Risk Definition

Market risk

The risk that all or a majority of the securities in a certain market — such as the stock or bond market — will decline in value because of factors such as adverse political or economic conditions, future expectations, investor confidence, or heavy institutional selling.

Limited number of stocks risk

The possibility that a single security's increase or decrease in value may have a greater impact on the portfolio's value and total return because the portfolio may hold larger positions in fewer securities than other portfolios.

Company size risk

The risk that investments in small- and/or medium-sized companies may be more volatile than those of larger companies because of limited financial resources or dependence on narrow product lines.

Nondiversification risk

A nondiversified portfolio has the flexibility to invest as much as 50% of its assets in as few as two issuers with no single issuer accounting for more than 25% of the portfolio. The remaining 50% of the portfolio must be diversified so that no more than 5% of its assets are invested in the securities of a single issuer. Because a nondiversified portfolio may invest its assets in fewer issuers, the value of portfolio shares may increase or decrease more rapidly than if it were fully diversified.

Foreign risk

The risk that foreign securities (particularly in emerging markets) may be adversely affected by political instability; changes in currency exchange rates; inefficient markets and higher transaction costs; foreign economic conditions; the imposition of economic or trade sanctions; or inadequate or different regulatory and accounting standards.

Real estate industry risk

This risk includes, among others, possible declines in the value of real estate; risks related to general and local economic conditions; possible lack of availability of mortgage funds; overbuilding; extended vacancies of properties; increases in competition; property taxes and operating expenses; changes in zoning laws; costs resulting from the cleanup of, and liability to third parties resulting from, environmental problems; casualty for condemnation losses; uninsured damages from floods, earthquakes, or other natural disasters; limitations on and variations in rents; and changes in interest rates.

Derivatives risk

Derivatives contracts, such as options, futures, and swaps, may involve additional expenses (such as the payment of premiums) and are subject to significant loss if a security or a securities index to which a derivatives contract is associated moves in the opposite direction from what the portfolio manager anticipated. Derivatives contracts are also subject to the risk that the counterparty may fail to perform its obligations under the contract due to financial difficulties (such as a bankruptcy or reorganization).

Liquidity risk

The possibility that securities cannot be readily sold within seven days at approximately the price at which a portfolio has valued them.

Investments not guaranteed by
Delaware Management Company
(Manager) or its affiliates

Neither the Manager nor its affiliates noted in this document are authorized deposit-taking institutions for the purposes of the Banking Act 1959 (Commonwealth of Australia). The obligations of these entities do not represent deposits or other liabilities of Macquarie Bank Limited (MBL). MBL does not guarantee or otherwise provide assurance in respect of the obligations of these entities, unless noted otherwise.

How has The Select 20 Portfolio performed?

The bar chart and table below provide some indication of the risks of investing in the Portfolio by showing changes in the Portfolio's performance from year to year and by showing how the Portfolio's average annual total returns for the 1-, 5-, and 10-year periods compare with those of a broad measure of market performance. The Portfolio's past performance (before and after taxes) is not necessarily an indication of how it will perform in the future. The returns reflect any expense caps in effect during these periods. The returns would be lower without the expense caps. You may obtain the Portfolio's most recently available month-end performance by calling 800 231-8002 or by visiting our website at delawareinvestments.com/institutional. On Feb. 28, 2008, the Portfolio changed its investment strategy to limit its investments to no less than 15 securities and no more than 25 securities. The performance prior to Feb. 28, 2008 is that of the Portfolio's predecessor, The All-Cap Growth Equity Portfolio.

Year-by-year total return (The Select 20 Portfolio)

Bar Chart

During the periods illustrated in this bar chart, The Select 20 Portfolio's highest quarterly return was 18.57% for the quarter ended June 30, 2009 and its lowest quarterly return was -21.91% for the quarter ended Dec. 31, 2008.

Average annual total returns for periods ended December 31, 2015

Average Annual Total Returns Equity Oriented or Fixed Income Oriented Funds The Select 20 Portfolio
1 Year
5 Years
10 Years
DPT CLASS
4.72% 14.48% 7.88%
DPT CLASS After Taxes on Distributions
0.15% 11.77% 6.59%
DPT CLASS After Taxes on Distributions and sale of Portfolio shares
6.35% 11.52% 6.36%
Russell 3000® Growth Index
5.09% 13.30% 8.49%

Russell Investment Group is the source and owner of the trademarks, service marks, and copyrights related to the Russell Indexes. Russell is a trademark of the Russell Investment Group.
Actual after-tax returns depend on the investor's individual tax situation and may differ from the returns shown. After-tax returns are not relevant for shares held in tax-deferred investment vehicles such as employer-sponsored 401(k) plans and individual retirement accounts (IRAs). The after-tax returns shown are calculated using the highest individual federal marginal income tax rates in effect during the Portfolio's lifetime and do not reflect the impact of state and local taxes.

v2.4.1.9
Label Element Value
Risk/Return: rr_RiskReturnAbstract  
Risk/Return, Heading rr_RiskReturnHeading

The Select 20 Portfolio

Investment Objective, Heading rr_ObjectiveHeading

What is the Portfolio's investment objective?

Investment Objective, Primary rr_ObjectivePrimaryTextBlock

The Select 20 Portfolio seeks long-term capital appreciation.

Expense, Heading rr_ExpenseHeading

What are the Portfolio's fees and expenses?

Expense, Narrative rr_ExpenseNarrativeTextBlock

The table below describes the fees and expenses that you may pay if you buy and hold shares of the Portfolio.

Operating Expenses, Caption rr_OperatingExpensesCaption

Annual portfolio operating expenses (expenses that you pay each year as a percentage of the value of your investment)

Fee Waiver or Reimbursement over Assets, Date of Termination rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination
Feb. 28, 2017
Portfolio Turnover, Heading rr_PortfolioTurnoverHeading

Portfolio turnover

Portfolio Turnover rr_PortfolioTurnoverTextBlock

The Portfolio pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Portfolio shares are held in a taxable account. These costs, which are not reflected in annual portfolio operating expenses or in the example, affect the Portfolio's performance. During the most recent fiscal year, the Portfolio's portfolio turnover rate was 31% of the average value of its portfolio.

Portfolio Turnover, Rate rr_PortfolioTurnoverRate 31.00%rr_PortfolioTurnoverRate
Expense Example, Heading rr_ExpenseExampleHeading

Example

Expense Example, Narrative rr_ExpenseExampleNarrativeTextBlock

This example is intended to help you compare the cost of investing in the Portfolio with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the Portfolio for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and reflects the Manager's expense waivers and reimbursements for the 1-year contractual period and the total operating expenses without waivers for years 2 through 10. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Investment Strategy, Heading rr_StrategyHeading

What are the Portfolio's principal investment strategies?

Investment Strategy, Narrative rr_StrategyNarrativeTextBlock

The Portfolio seeks to achieve its objective by investing in a portfolio of 20 securities. The Portfolio will invest in no fewer than 15 and no more than 25 equity securities. The Portfolio is considered “nondiversified” as defined in the Investment Company Act of 1940, as amended (1940 Act), which means that it may invest in a smaller number of issuers than a diversified mutual fund.

The portfolio managers invest primarily in common stocks of companies that they believe have long-term capital appreciation potential and are expected to grow faster than the U.S. economy. The portfolio managers consider companies of any size or market capitalization. Using a bottom-up approach, the portfolio managers seek to select securities of companies that have large market opportunities. Companies that have large market opportunities are those that, in the portfolio managers' opinion, may have a large demand or market for their goods or services. The portfolio managers also consider a company's operational efficiencies, management plans for capital allocation, and the company's shareholder orientation.

The portfolio managers research individual companies and analyze economic and market conditions, seeking to identify the securities or market sectors that they think are the best investments for the Portfolio. Specifically, the portfolio managers look for structural changes in the economy, industry, or product cycle changes, or changes in management, targeting those companies that can best capitalize on such changes. The following is a description of how the portfolio managers pursue the Portfolio's investment goals.

The portfolio managers strive to identify companies that offer the potential for long-term price appreciation because they are likely to experience sustainable free cash-flow growth. Using a bottom-up approach, the portfolio managers look for companies that they believe:

have attractive end-market potential or dominance of a profitable niche market, dominant business models, and strong cash-flow generation;
 

demonstrate operational and scale efficiencies;
 

have demonstrated expertise for capital allocation; or
 

have clear shareholder-oriented governance and compensation policies.

All of these factors give the portfolio managers insight into the outlook for a company, helping the portfolio managers to identify companies poised for sustainable free cash-flow growth. The portfolio managers believe that sustainable free cash-flow growth, if it occurs, may result in price appreciation for the company's stock.

The portfolio managers maintain a diversified portfolio, typically holding a mix of different stocks, representing a wide array of industries and a mix of small-, medium-, and large-size companies.

The portfolio managers may invest up to 20% of the Portfolio's net assets in securities of foreign issuers, including issuers located in emerging markets.

The portfolio managers may invest in real estate investment trusts (REITs).

Strategy Portfolio Concentration rr_StrategyPortfolioConcentration
The portfolio managers invest primarily in common stocks of companies that they believe have long-term capital appreciation potential and are expected to grow faster than the U.S. economy. The portfolio managers consider companies of any size or market capitalization.
Risk, Heading rr_RiskHeading

What are the principal risks of investing in the Portfolio?

Risk, Narrative rr_RiskNarrativeTextBlock

Investing in any mutual fund involves the risk that you may lose part or all of the money you invest. Over time, the value of your investment in the Portfolio will increase and decrease according to changes in the value of the securities in its portfolio. Principal risks include:

Risk Definition

Market risk

The risk that all or a majority of the securities in a certain market — such as the stock or bond market — will decline in value because of factors such as adverse political or economic conditions, future expectations, investor confidence, or heavy institutional selling.

Limited number of stocks risk

The possibility that a single security's increase or decrease in value may have a greater impact on the portfolio's value and total return because the portfolio may hold larger positions in fewer securities than other portfolios.

Company size risk

The risk that investments in small- and/or medium-sized companies may be more volatile than those of larger companies because of limited financial resources or dependence on narrow product lines.

Nondiversification risk

A nondiversified portfolio has the flexibility to invest as much as 50% of its assets in as few as two issuers with no single issuer accounting for more than 25% of the portfolio. The remaining 50% of the portfolio must be diversified so that no more than 5% of its assets are invested in the securities of a single issuer. Because a nondiversified portfolio may invest its assets in fewer issuers, the value of portfolio shares may increase or decrease more rapidly than if it were fully diversified.

Foreign risk

The risk that foreign securities (particularly in emerging markets) may be adversely affected by political instability; changes in currency exchange rates; inefficient markets and higher transaction costs; foreign economic conditions; the imposition of economic or trade sanctions; or inadequate or different regulatory and accounting standards.

Real estate industry risk

This risk includes, among others, possible declines in the value of real estate; risks related to general and local economic conditions; possible lack of availability of mortgage funds; overbuilding; extended vacancies of properties; increases in competition; property taxes and operating expenses; changes in zoning laws; costs resulting from the cleanup of, and liability to third parties resulting from, environmental problems; casualty for condemnation losses; uninsured damages from floods, earthquakes, or other natural disasters; limitations on and variations in rents; and changes in interest rates.

Derivatives risk

Derivatives contracts, such as options, futures, and swaps, may involve additional expenses (such as the payment of premiums) and are subject to significant loss if a security or a securities index to which a derivatives contract is associated moves in the opposite direction from what the portfolio manager anticipated. Derivatives contracts are also subject to the risk that the counterparty may fail to perform its obligations under the contract due to financial difficulties (such as a bankruptcy or reorganization).

Liquidity risk

The possibility that securities cannot be readily sold within seven days at approximately the price at which a portfolio has valued them.

Investments not guaranteed by
Delaware Management Company
(Manager) or its affiliates

Neither the Manager nor its affiliates noted in this document are authorized deposit-taking institutions for the purposes of the Banking Act 1959 (Commonwealth of Australia). The obligations of these entities do not represent deposits or other liabilities of Macquarie Bank Limited (MBL). MBL does not guarantee or otherwise provide assurance in respect of the obligations of these entities, unless noted otherwise.

Risk, Lose Money rr_RiskLoseMoney
Investing in any mutual fund involves the risk that you may lose part or all of the money you invest.
Risk, Nondiversified Status rr_RiskNondiversifiedStatus
A nondiversified portfolio has the flexibility to invest as much as 50% of its assets in as few as two issuers with no single issuer accounting for more than 25% of the portfolio. The remaining 50% of the portfolio must be diversified so that no more than 5% of its assets are invested in the securities of a single issuer. Because a nondiversified portfolio may invest its assets in fewer issuers, the value of portfolio shares may increase or decrease more rapidly than if it were fully diversified.
Risk, Not Insured Depository Institution rr_RiskNotInsuredDepositoryInstitution
Neither the Manager nor its affiliates noted in this document are authorized deposit-taking institutions for the purposes of the Banking Act 1959 (Commonwealth of Australia). The obligations of these entities do not represent deposits or other liabilities of Macquarie Bank Limited (MBL). MBL does not guarantee or otherwise provide assurance in respect of the obligations of these entities, unless noted otherwise.
Bar Chart and Performance Table, Heading rr_BarChartAndPerformanceTableHeading

How has The Select 20 Portfolio performed?

Performance, Narrative rr_PerformanceNarrativeTextBlock

The bar chart and table below provide some indication of the risks of investing in the Portfolio by showing changes in the Portfolio's performance from year to year and by showing how the Portfolio's average annual total returns for the 1-, 5-, and 10-year periods compare with those of a broad measure of market performance. The Portfolio's past performance (before and after taxes) is not necessarily an indication of how it will perform in the future. The returns reflect any expense caps in effect during these periods. The returns would be lower without the expense caps. You may obtain the Portfolio's most recently available month-end performance by calling 800 231-8002 or by visiting our website at delawareinvestments.com/institutional. On Feb. 28, 2008, the Portfolio changed its investment strategy to limit its investments to no less than 15 securities and no more than 25 securities. The performance prior to Feb. 28, 2008 is that of the Portfolio's predecessor, The All-Cap Growth Equity Portfolio.

Performance, Information Illustrates Variability of Returns rr_PerformanceInformationIllustratesVariabilityOfReturns
The bar chart and table below provide some indication of the risks of investing in the Portfolio by showing changes in the Portfolio's performance from year to year and by showing how the Portfolio's average annual total returns for the 1-, 5-, and 10-year periods compare with those of a broad measure of market performance.
Performance Availability Phone rr_PerformanceAvailabilityPhone
800 231-8002
Performance Availability Website Address rr_PerformanceAvailabilityWebSiteAddress
delawareinvestments.com/institutional
Performance Past Does Not Indicate Future rr_PerformancePastDoesNotIndicateFuture
The Portfolio's past performance (before and after taxes) is not necessarily an indication of how it will perform in the future.
Bar Chart, Heading rr_BarChartHeading

Year-by-year total return (The Select 20 Portfolio)

Bar Chart, Closing rr_BarChartClosingTextBlock

During the periods illustrated in this bar chart, The Select 20 Portfolio's highest quarterly return was 18.57% for the quarter ended June 30, 2009 and its lowest quarterly return was -21.91% for the quarter ended Dec. 31, 2008.

Highest Quarterly Return, Label rr_HighestQuarterlyReturnLabel
highest quarterly return
Highest Quarterly Return, Date rr_BarChartHighestQuarterlyReturnDate Jun. 30, 2009
Highest Quarterly Return rr_BarChartHighestQuarterlyReturn 18.57%rr_BarChartHighestQuarterlyReturn
Lowest Quarterly Return, Label rr_LowestQuarterlyReturnLabel
lowest quarterly return
Lowest Quarterly Return, Date rr_BarChartLowestQuarterlyReturnDate Dec. 31, 2008
Lowest Quarterly Return rr_BarChartLowestQuarterlyReturn (21.91%)rr_BarChartLowestQuarterlyReturn
Performance Table, Heading rr_PerformanceTableHeading

Average annual total returns for periods ended December 31, 2015

Performance Table Uses Highest Federal Rate rr_PerformanceTableUsesHighestFederalRate
The after-tax returns shown are calculated using the highest individual federal marginal income tax rates in effect during the Portfolio's lifetime and do not reflect the impact of state and local taxes.
Performance Table Not Relevant to Tax Deferred rr_PerformanceTableNotRelevantToTaxDeferred
After-tax returns are not relevant for shares held in tax-deferred investment vehicles such as employer-sponsored 401(k) plans and individual retirement accounts (IRAs).
Performance Table, Closing rr_PerformanceTableClosingTextBlock

Russell Investment Group is the source and owner of the trademarks, service marks, and copyrights related to the Russell Indexes. Russell is a trademark of the Russell Investment Group.
Actual after-tax returns depend on the investor's individual tax situation and may differ from the returns shown. After-tax returns are not relevant for shares held in tax-deferred investment vehicles such as employer-sponsored 401(k) plans and individual retirement accounts (IRAs). The after-tax returns shown are calculated using the highest individual federal marginal income tax rates in effect during the Portfolio's lifetime and do not reflect the impact of state and local taxes.

Russell 3000® Growth Index
 
Risk/Return: rr_RiskReturnAbstract  
Index No Deduction for Fees, Expenses, Taxes rr_IndexNoDeductionForFeesExpensesTaxes
reflects no deduction for fees, expenses, or taxes
1 Year rr_AverageAnnualReturnYear01 5.09%rr_AverageAnnualReturnYear01
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10 Years rr_AverageAnnualReturnYear10 8.49%rr_AverageAnnualReturnYear10
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DPT CLASS
 
Risk/Return: rr_RiskReturnAbstract  
Management fees rr_ManagementFeesOverAssets 0.75%rr_ManagementFeesOverAssets
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Distribution and service (12b-1) fees rr_DistributionAndService12b1FeesOverAssets none
Other expenses rr_OtherExpensesOverAssets 0.14%rr_OtherExpensesOverAssets
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[1] The Portfolio's investment manager, Delaware Management Company (Manager), has contractually agreed to waive all or a portion of its investment advisory fees and/or pay/ reimburse expenses (excluding any 12b-1 fees, acquired fund fees and expenses, taxes, interest, expenses, short sale and dividend interest expenses, brokerage fees, certain insurance costs, and nonroutine expenses or costs, including, but not limited to, those relating to reorganizations, litigation, conducting shareholder meetings, and liquidations) in order to prevent total annual portfolio operating expenses from exceeding 0.89% of the Portfolio's average daily net assets from Feb. 26, 2016 through Feb. 28, 2017. These waivers and reimbursements may only be terminated by agreement of the Manager and the Portfolio.
v2.4.1.9
Equity Oriented or Fixed Income Oriented Funds | The Labor Select International Equity Portfolio

The Labor Select International Equity Portfolio

What is the Portfolio's investment objective?

The Labor Select International Equity Portfolio seeks maximum long-term total return.

What are the Portfolio's fees and expenses?

The table below describes the fees and expenses that you may pay if you buy and hold shares of the Portfolio.

Annual portfolio operating expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses
Equity Oriented or Fixed Income Oriented Funds
The Labor Select International Equity Portfolio
DPT CLASS
Management fees 0.75%rr_ManagementFeesOverAssets
Distribution and service (12b-1) fees none
Other expenses 0.12%rr_OtherExpensesOverAssets
Total annual portfolio operating expenses 0.87%rr_ExpensesOverAssets

Example

This example is intended to help you compare the cost of investing in the Portfolio with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the Portfolio for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the Portfolio's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example (USD $)
1 Year
3 Years
5 Years
10 Years
Equity Oriented or Fixed Income Oriented Funds The Labor Select International Equity Portfolio DPT CLASS
89 278 482 1,073

Portfolio turnover

The Portfolio pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Portfolio shares are held in a taxable account. These costs, which are not reflected in annual portfolio operating expenses or in the example, affect the Portfolio's performance. During the most recent fiscal year, the Portfolio's portfolio turnover rate was 20% of the average value of its portfolio.

What are the Portfolio's principal investment strategies?

The Portfolio will primarily invest in equity securities of companies that are organized, have a majority of their assets, or derive most of their operating income outside of the U.S., and which, in the opinion of the Portfolio's portfolio managers, are undervalued at the time of purchase based on the rigorous fundamental analysis that the portfolio managers employ. In addition to following these quantitative guidelines, the Sub-advisor will select securities of issuers that present certain characteristics that are compatible or operate in accordance with certain investment policies or restrictions followed by organized labor.

Under normal circumstances, the Portfolio will invest at least 80% of its net assets, plus any borrowings for investment purposes, in equity securities (80% Policy). The Portfolio's 80% Policy may be changed without shareholder approval. However, shareholders will be given notice at least 60 days prior to any such change. Under normal circumstances, the Portfolio will invest at least 40% of its total assets in securities of non-U.S. issuers. This policy is in addition to the 80% Policy.

In selecting portfolio securities, the portfolio managers emphasize strong performance in falling markets relative to other mutual funds focusing on international equity investments. Equity securities include, but are not limited to, common stocks, securities convertible into common stocks, securities having common stock characteristics, such as rights and warrants to purchase common stocks, and preferred shares. To the extent that this Portfolio invests in convertible debt securities, those securities will be purchased on the basis of their equity characteristics, and ratings of those securities, if any, will not be an important factor in their selection. Additionally, the Portfolio may, from time to time, hold its assets in cash (which may be U.S. dollars or foreign currency, including the euro) or may invest in short-term debt securities or other money market instruments. Except when a temporary defensive approach is appropriate, the Portfolio generally will not hold more than 5% of its assets in cash or such short-term instruments. From time to time, the Portfolio may invest up to 30% of its net assets in securities of issuers in the commercial banking industry; to the extent the Portfolio invests 30% of its net assets in such securities, it may be slightly more sensitive to movement in the commercial banking industry.

The Portfolio may make limited use (not more than 15% of its assets) of foreign fixed income securities when, in the portfolio managers' opinion, attractive opportunities exist relative to those available through equity securities or the short-term investments described above. The foreign fixed income securities in which the Portfolio may invest may be U.S. dollar or foreign currency denominated, including the euro, and may include obligations of foreign governments, foreign government agencies, supranational organizations or corporations, and other private entities. Such governmental fixed income securities will be, at the time of purchase, of the highest quality (for example, AAA by S&P or Aaa by Moody's) or of comparable quality. Corporate fixed income securities will be, at the time of purchase, rated in one of the top two rating categories (for example, AAA and AA by S&P or Aaa and Aa by Moody's) or of comparable quality.

The portfolio managers' approach in selecting investments for the Portfolio is primarily quantitatively oriented to individual stock selection and is value driven. In selecting stocks for the Portfolio, the portfolio managers identify those stocks that they believe will provide the highest total return over a market cycle, taking into consideration the movement in the price of the individual security, the impact of currency adjustment on a U.S.-domiciled, dollar-based investor, and the investment guidelines described below. The portfolio managers conduct extensive fundamental research on a global basis, and it is through this research effort that securities with the potential for maximum long-term total return are identified. The center of the fundamental research effort is a value-oriented dividend discount methodology applied to individual securities and market analysis that isolates value across country boundaries. The portfolio managers' approach focuses on future anticipated dividends and discounts the value of those dividends back to what they would be worth if they were being paid today. Comparisons of the values of different possible investments are then made.

Supplementing the portfolio managers' quantitative approach to stock selection, the portfolio managers also attempt to follow certain qualitative investment guidelines that seek to identify issuers that present certain characteristics that are compatible or operate in accordance with certain investment policies or restrictions followed by organized labor. These qualitative investment guidelines include country screens, as well as additional issuer-specific criteria. The country screens require that the securities are of companies domiciled in those countries that are included in the MSCI EAFE (Europe, Australasia, and Far East) Index and Canada, as long as the country does not appear on any list of prohibited or boycotted nations of the AFL-CIO or certain other labor organizations. Nations that are currently in this Index include, among others, Japan, the United Kingdom, Germany, France, and the Netherlands. In addition, the Portfolio will tend to favor investments in issuers located in those countries that the portfolio managers perceive as enjoying favorable relations with the U.S. Pursuant to the Portfolio's issuer-specific criteria, the Portfolio will: (1) invest only in companies that are publicly traded; (2) focus on companies that show, in the portfolio managers' opinion, evidence of pursuing fair labor practices; (3) focus on companies that have not been subject to penalties or tariffs imposed by applicable U.S. government agencies for unfair trade practices within the previous two years; and (4) not invest in initial public offerings. Evidence of pursuing fair labor practices would include whether a company has demonstrated patterns of noncompliance with applicable labor or health and safety laws. The qualitative labor sensitivity factors that the portfolio managers will utilize in selecting securities will vary over time, and will be solely in the portfolio managers' discretion.

The portfolio managers do not normally intend to respond to short-term market fluctuations or to acquire securities for the purpose of short-term trading; however, the portfolio managers may take advantage of short-term opportunities that are consistent with the Portfolio's investment objective. It is anticipated that the annual turnover rate of the Portfolio, under normal circumstances, will generally not exceed 100%.

Currency considerations carry a special risk for a portfolio of international securities, and the portfolio managers use a purchasing power parity approach to evaluate currency risk. In this regard, the Portfolio may actively carry out hedging activities, and may invest in forward foreign currency exchange contracts to hedge currency risks associated with the purchase of individual securities denominated in a particular currency.

What are the principal risks of investing in the Portfolio?

Investing in any mutual fund involves the risk that you may lose part or all of the money you invest. Over time, the value of your investment in the Portfolio will increase and decrease according to changes in the value of the securities in its portfolio. Principal risks include:

Risk Definition

Market risk

The risk that all or a majority of the securities in a certain market — such as the stock or bond market — will decline in value because of factors such as adverse political or economic conditions, future expectations, investor confidence, or heavy institutional selling.

Foreign risk

The risk that foreign securities (particularly in emerging markets) may be adversely affected by political instability; changes in currency exchange rates; inefficient markets and higher transaction costs; foreign economic conditions; the imposition of economic or trade sanctions; or inadequate or different regulatory and accounting standards.

Foreign government/
supranational securities risk

The risk that a foreign government or government-related issuer may be unable to make timely payments on its external debt obligations.

Currency risk

The risk that the value of a portfolio's investments may be negatively affected by changes in foreign currency exchange rates.

Derivatives risk

Derivatives contracts, such as options, futures, and swaps, may involve additional expenses (such as the payment of premiums) and are subject to significant loss if a security or a securities index to which a derivatives contract is associated moves in the opposite direction from what the portfolio manager anticipated. Derivatives contracts are also subject to the risk that the counterparty may fail to perform its obligations under the contract due to financial difficulties (such as a bankruptcy or reorganization).

Interest rate risk

The risk that securities will decrease in value if interest rates rise. The risk is generally associated with bonds; however, because companies in the real estate sector and smaller companies often borrow money to finance their operations, they may be adversely affected by rising interest rates.

Liquidity risk

The possibility that securities cannot be readily sold within seven days at approximately the price at which a portfolio has valued them.

Investments not guaranteed by
Delaware Management Company
(Manager) or its affiliates

Neither the Manager nor its affiliates noted in this document are authorized deposit-taking institutions for the purposes of the Banking Act 1959 (Commonwealth of Australia). The obligations of these entities do not represent deposits or other liabilities of Macquarie Bank Limited (MBL). MBL does not guarantee or otherwise provide assurance in respect of the obligations of these entities, unless noted otherwise.

How has The Labor Select International Equity Portfolio performed?

The bar chart and table below provide some indication of the risks of investing in the Portfolio by showing changes in the Portfolio's performance from year to year and by showing how the Portfolio's average annual total returns for the 1-, 5-, and 10-year periods compare with those of a broad measure of market performance. The Portfolio's past performance (before and after taxes) is not necessarily an indication of how it will perform in the future. The returns reflect any expense caps in effect during these periods. The returns would be lower without the expense caps. You may obtain the Portfolio's most recently available month-end performance by calling 800 231-8002 or by visiting our website at delawareinvestments.com/institutional.

Year-by-year total return (The Labor Select International Equity Portfolio)

Bar Chart

During the periods illustrated in this bar chart, The Labor Select International Equity Portfolio's highest quarterly return was 21.23% for the quarter ended June 30, 2009 and its lowest quarterly return was -17.66% for the quarter ended March 31, 2009.

Average annual total returns for periods ended December 31, 2015

Average Annual Total Returns Equity Oriented or Fixed Income Oriented Funds The Labor Select International Equity Portfolio
1 Year
5 Years
10 Years
DPT CLASS
(3.84%) 3.25% 2.94%
DPT CLASS After Taxes on Distributions
(4.34%) 2.43% 1.88%
DPT CLASS After Taxes on Distributions and sale of Portfolio shares
(1.50%) 2.59% 2.66%
MSCI EAFE Index (gross returns)
(0.39%) 4.07% 3.50%
MSCI EAFE Index (net returns)
(0.81%) 3.60% 3.03%

Actual after-tax returns depend on the investor's individual tax situation and may differ from the returns shown. After-tax returns are not relevant for shares held in tax-deferred investment vehicles such as employer-sponsored 401(k) plans and individual retirement accounts (IRAs). The after-tax returns shown are calculated using the highest individual federal marginal income tax rates in effect during the Portfolio's lifetime and do not reflect the impact of state and local taxes.

v2.4.1.9
Label Element Value
Risk/Return: rr_RiskReturnAbstract  
Risk/Return, Heading rr_RiskReturnHeading

The Labor Select International Equity Portfolio

Investment Objective, Heading rr_ObjectiveHeading

What is the Portfolio's investment objective?

Investment Objective, Primary rr_ObjectivePrimaryTextBlock

The Labor Select International Equity Portfolio seeks maximum long-term total return.

Expense, Heading rr_ExpenseHeading

What are the Portfolio's fees and expenses?

Expense, Narrative rr_ExpenseNarrativeTextBlock

The table below describes the fees and expenses that you may pay if you buy and hold shares of the Portfolio.

Operating Expenses, Caption rr_OperatingExpensesCaption

Annual portfolio operating expenses (expenses that you pay each year as a percentage of the value of your investment)

Portfolio Turnover, Heading rr_PortfolioTurnoverHeading

Portfolio turnover

Portfolio Turnover rr_PortfolioTurnoverTextBlock

The Portfolio pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Portfolio shares are held in a taxable account. These costs, which are not reflected in annual portfolio operating expenses or in the example, affect the Portfolio's performance. During the most recent fiscal year, the Portfolio's portfolio turnover rate was 20% of the average value of its portfolio.

Portfolio Turnover, Rate rr_PortfolioTurnoverRate 20.00%rr_PortfolioTurnoverRate
Expense Example, Heading rr_ExpenseExampleHeading

Example

Expense Example, Narrative rr_ExpenseExampleNarrativeTextBlock

This example is intended to help you compare the cost of investing in the Portfolio with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the Portfolio for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the Portfolio's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Investment Strategy, Heading rr_StrategyHeading

What are the Portfolio's principal investment strategies?

Investment Strategy, Narrative rr_StrategyNarrativeTextBlock

The Portfolio will primarily invest in equity securities of companies that are organized, have a majority of their assets, or derive most of their operating income outside of the U.S., and which, in the opinion of the Portfolio's portfolio managers, are undervalued at the time of purchase based on the rigorous fundamental analysis that the portfolio managers employ. In addition to following these quantitative guidelines, the Sub-advisor will select securities of issuers that present certain characteristics that are compatible or operate in accordance with certain investment policies or restrictions followed by organized labor.

Under normal circumstances, the Portfolio will invest at least 80% of its net assets, plus any borrowings for investment purposes, in equity securities (80% Policy). The Portfolio's 80% Policy may be changed without shareholder approval. However, shareholders will be given notice at least 60 days prior to any such change. Under normal circumstances, the Portfolio will invest at least 40% of its total assets in securities of non-U.S. issuers. This policy is in addition to the 80% Policy.

In selecting portfolio securities, the portfolio managers emphasize strong performance in falling markets relative to other mutual funds focusing on international equity investments. Equity securities include, but are not limited to, common stocks, securities convertible into common stocks, securities having common stock characteristics, such as rights and warrants to purchase common stocks, and preferred shares. To the extent that this Portfolio invests in convertible debt securities, those securities will be purchased on the basis of their equity characteristics, and ratings of those securities, if any, will not be an important factor in their selection. Additionally, the Portfolio may, from time to time, hold its assets in cash (which may be U.S. dollars or foreign currency, including the euro) or may invest in short-term debt securities or other money market instruments. Except when a temporary defensive approach is appropriate, the Portfolio generally will not hold more than 5% of its assets in cash or such short-term instruments. From time to time, the Portfolio may invest up to 30% of its net assets in securities of issuers in the commercial banking industry; to the extent the Portfolio invests 30% of its net assets in such securities, it may be slightly more sensitive to movement in the commercial banking industry.

The Portfolio may make limited use (not more than 15% of its assets) of foreign fixed income securities when, in the portfolio managers' opinion, attractive opportunities exist relative to those available through equity securities or the short-term investments described above. The foreign fixed income securities in which the Portfolio may invest may be U.S. dollar or foreign currency denominated, including the euro, and may include obligations of foreign governments, foreign government agencies, supranational organizations or corporations, and other private entities. Such governmental fixed income securities will be, at the time of purchase, of the highest quality (for example, AAA by S&P or Aaa by Moody's) or of comparable quality. Corporate fixed income securities will be, at the time of purchase, rated in one of the top two rating categories (for example, AAA and AA by S&P or Aaa and Aa by Moody's) or of comparable quality.

The portfolio managers' approach in selecting investments for the Portfolio is primarily quantitatively oriented to individual stock selection and is value driven. In selecting stocks for the Portfolio, the portfolio managers identify those stocks that they believe will provide the highest total return over a market cycle, taking into consideration the movement in the price of the individual security, the impact of currency adjustment on a U.S.-domiciled, dollar-based investor, and the investment guidelines described below. The portfolio managers conduct extensive fundamental research on a global basis, and it is through this research effort that securities with the potential for maximum long-term total return are identified. The center of the fundamental research effort is a value-oriented dividend discount methodology applied to individual securities and market analysis that isolates value across country boundaries. The portfolio managers' approach focuses on future anticipated dividends and discounts the value of those dividends back to what they would be worth if they were being paid today. Comparisons of the values of different possible investments are then made.

Supplementing the portfolio managers' quantitative approach to stock selection, the portfolio managers also attempt to follow certain qualitative investment guidelines that seek to identify issuers that present certain characteristics that are compatible or operate in accordance with certain investment policies or restrictions followed by organized labor. These qualitative investment guidelines include country screens, as well as additional issuer-specific criteria. The country screens require that the securities are of companies domiciled in those countries that are included in the MSCI EAFE (Europe, Australasia, and Far East) Index and Canada, as long as the country does not appear on any list of prohibited or boycotted nations of the AFL-CIO or certain other labor organizations. Nations that are currently in this Index include, among others, Japan, the United Kingdom, Germany, France, and the Netherlands. In addition, the Portfolio will tend to favor investments in issuers located in those countries that the portfolio managers perceive as enjoying favorable relations with the U.S. Pursuant to the Portfolio's issuer-specific criteria, the Portfolio will: (1) invest only in companies that are publicly traded; (2) focus on companies that show, in the portfolio managers' opinion, evidence of pursuing fair labor practices; (3) focus on companies that have not been subject to penalties or tariffs imposed by applicable U.S. government agencies for unfair trade practices within the previous two years; and (4) not invest in initial public offerings. Evidence of pursuing fair labor practices would include whether a company has demonstrated patterns of noncompliance with applicable labor or health and safety laws. The qualitative labor sensitivity factors that the portfolio managers will utilize in selecting securities will vary over time, and will be solely in the portfolio managers' discretion.

The portfolio managers do not normally intend to respond to short-term market fluctuations or to acquire securities for the purpose of short-term trading; however, the portfolio managers may take advantage of short-term opportunities that are consistent with the Portfolio's investment objective. It is anticipated that the annual turnover rate of the Portfolio, under normal circumstances, will generally not exceed 100%.

Currency considerations carry a special risk for a portfolio of international securities, and the portfolio managers use a purchasing power parity approach to evaluate currency risk. In this regard, the Portfolio may actively carry out hedging activities, and may invest in forward foreign currency exchange contracts to hedge currency risks associated with the purchase of individual securities denominated in a particular currency.

Strategy Portfolio Concentration rr_StrategyPortfolioConcentration
Under normal circumstances, the Portfolio will invest at least 80% of its net assets, plus any borrowings for investment purposes, in equity securities (80% Policy). The Portfolio's 80% Policy may be changed without shareholder approval. However, shareholders will be given notice at least 60 days prior to any such change. Under normal circumstances, the Portfolio will invest at least 40% of its total assets in securities of non-U.S. issuers. This policy is in addition to the 80% Policy.
Risk, Heading rr_RiskHeading

What are the principal risks of investing in the Portfolio?

Risk, Narrative rr_RiskNarrativeTextBlock

Investing in any mutual fund involves the risk that you may lose part or all of the money you invest. Over time, the value of your investment in the Portfolio will increase and decrease according to changes in the value of the securities in its portfolio. Principal risks include:

Risk Definition

Market risk

The risk that all or a majority of the securities in a certain market — such as the stock or bond market — will decline in value because of factors such as adverse political or economic conditions, future expectations, investor confidence, or heavy institutional selling.

Foreign risk

The risk that foreign securities (particularly in emerging markets) may be adversely affected by political instability; changes in currency exchange rates; inefficient markets and higher transaction costs; foreign economic conditions; the imposition of economic or trade sanctions; or inadequate or different regulatory and accounting standards.

Foreign government/
supranational securities risk

The risk that a foreign government or government-related issuer may be unable to make timely payments on its external debt obligations.

Currency risk

The risk that the value of a portfolio's investments may be negatively affected by changes in foreign currency exchange rates.

Derivatives risk

Derivatives contracts, such as options, futures, and swaps, may involve additional expenses (such as the payment of premiums) and are subject to significant loss if a security or a securities index to which a derivatives contract is associated moves in the opposite direction from what the portfolio manager anticipated. Derivatives contracts are also subject to the risk that the counterparty may fail to perform its obligations under the contract due to financial difficulties (such as a bankruptcy or reorganization).

Interest rate risk

The risk that securities will decrease in value if interest rates rise. The risk is generally associated with bonds; however, because companies in the real estate sector and smaller companies often borrow money to finance their operations, they may be adversely affected by rising interest rates.

Liquidity risk

The possibility that securities cannot be readily sold within seven days at approximately the price at which a portfolio has valued them.

Investments not guaranteed by
Delaware Management Company
(Manager) or its affiliates

Neither the Manager nor its affiliates noted in this document are authorized deposit-taking institutions for the purposes of the Banking Act 1959 (Commonwealth of Australia). The obligations of these entities do not represent deposits or other liabilities of Macquarie Bank Limited (MBL). MBL does not guarantee or otherwise provide assurance in respect of the obligations of these entities, unless noted otherwise.

Risk, Lose Money rr_RiskLoseMoney
Investing in any mutual fund involves the risk that you may lose part or all of the money you invest.
Risk, Not Insured Depository Institution rr_RiskNotInsuredDepositoryInstitution
Neither the Manager nor its affiliates noted in this document are authorized deposit-taking institutions for the purposes of the Banking Act 1959 (Commonwealth of Australia). The obligations of these entities do not represent deposits or other liabilities of Macquarie Bank Limited (MBL). MBL does not guarantee or otherwise provide assurance in respect of the obligations of these entities, unless noted otherwise.
Bar Chart and Performance Table, Heading rr_BarChartAndPerformanceTableHeading

How has The Labor Select International Equity Portfolio performed?

Performance, Narrative rr_PerformanceNarrativeTextBlock

The bar chart and table below provide some indication of the risks of investing in the Portfolio by showing changes in the Portfolio's performance from year to year and by showing how the Portfolio's average annual total returns for the 1-, 5-, and 10-year periods compare with those of a broad measure of market performance. The Portfolio's past performance (before and after taxes) is not necessarily an indication of how it will perform in the future. The returns reflect any expense caps in effect during these periods. The returns would be lower without the expense caps. You may obtain the Portfolio's most recently available month-end performance by calling 800 231-8002 or by visiting our website at delawareinvestments.com/institutional.

Performance, Information Illustrates Variability of Returns rr_PerformanceInformationIllustratesVariabilityOfReturns
The bar chart and table below provide some indication of the risks of investing in the Portfolio by showing changes in the Portfolio's performance from year to year and by showing how the Portfolio's average annual total returns for the 1-, 5-, and 10-year periods compare with those of a broad measure of market performance.
Performance Availability Phone rr_PerformanceAvailabilityPhone
800 231-8002
Performance Availability Website Address rr_PerformanceAvailabilityWebSiteAddress
delawareinvestments.com/institutional
Performance Past Does Not Indicate Future rr_PerformancePastDoesNotIndicateFuture
The Portfolio's past performance (before and after taxes) is not necessarily an indication of how it will perform in the future.
Bar Chart, Heading rr_BarChartHeading

Year-by-year total return (The Labor Select International Equity Portfolio)

Bar Chart, Closing rr_BarChartClosingTextBlock

During the periods illustrated in this bar chart, The Labor Select International Equity Portfolio's highest quarterly return was 21.23% for the quarter ended June 30, 2009 and its lowest quarterly return was -17.66% for the quarter ended March 31, 2009.

Highest Quarterly Return, Label rr_HighestQuarterlyReturnLabel
highest quarterly return
Highest Quarterly Return, Date rr_BarChartHighestQuarterlyReturnDate Jun. 30, 2009
Highest Quarterly Return rr_BarChartHighestQuarterlyReturn 21.23%rr_BarChartHighestQuarterlyReturn
Lowest Quarterly Return, Label rr_LowestQuarterlyReturnLabel
lowest quarterly return
Lowest Quarterly Return, Date rr_BarChartLowestQuarterlyReturnDate Mar. 31, 2009
Lowest Quarterly Return rr_BarChartLowestQuarterlyReturn (17.66%)rr_BarChartLowestQuarterlyReturn
Performance Table, Heading rr_PerformanceTableHeading

Average annual total returns for periods ended December 31, 2015

Performance Table Uses Highest Federal Rate rr_PerformanceTableUsesHighestFederalRate
The after-tax returns shown are calculated using the highest individual federal marginal income tax rates in effect during the Portfolio's lifetime and do not reflect the impact of state and local taxes.
Performance Table Not Relevant to Tax Deferred rr_PerformanceTableNotRelevantToTaxDeferred
After-tax returns are not relevant for shares held in tax-deferred investment vehicles such as employer-sponsored 401(k) plans and individual retirement accounts (IRAs).
Performance Table, Closing rr_PerformanceTableClosingTextBlock

Actual after-tax returns depend on the investor's individual tax situation and may differ from the returns shown. After-tax returns are not relevant for shares held in tax-deferred investment vehicles such as employer-sponsored 401(k) plans and individual retirement accounts (IRAs). The after-tax returns shown are calculated using the highest individual federal marginal income tax rates in effect during the Portfolio's lifetime and do not reflect the impact of state and local taxes.

MSCI EAFE Index (gross returns)
 
Risk/Return: rr_RiskReturnAbstract  
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v2.4.1.9
Equity Oriented or Fixed Income Oriented Funds | The Emerging Markets Portfolio

The Emerging Markets Portfolio

What is the Portfolio's investment objective?

The Emerging Markets Portfolio seeks long-term capital appreciation.

What are the Portfolio's fees and expenses?

The table below describes the fees and expenses that you may pay if you buy and hold shares of the Portfolio.

Shareholder fees (fees paid directly from your investment)

Shareholder Fees
Equity Oriented or Fixed Income Oriented Funds
The Emerging Markets Portfolio
DPT CLASS
Maximum sales charge (load) imposed on purchases as apercentage of offering price none
Maximum contingent deferred sales charge (load) as a percentage of original purchase price or redemption price, whichever is lower none
Purchase reimbursement fees [1] 0.55%rr_ExchangeFeeOverRedemption
Redemption reimbursement fees [1] 0.55%rr_RedemptionFeeOverRedemption
[1] The purchase reimbursement fees and redemption reimbursement fees are paid to the Portfolio. These fees are designed to reflect an approximation of the brokerage and other transaction costs associated with the investment of an investor's purchase amount or the disposition of assets to meet redemptions, and to limit the extent to which the Portfolio (and, indirectly, the Portfolio's existing shareholders) would have to bear such costs. In lieu of the reimbursement fees, investors in The Emerging Markets Portfolio may be permitted to utilize alternative purchase and redemption methods designed to accomplish the same economic effect as the reimbursement fees.

Annual portfolio operating expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses
Equity Oriented or Fixed Income Oriented Funds
The Emerging Markets Portfolio
DPT CLASS
Management fees 1.00%rr_ManagementFeesOverAssets
Distribution and service (12b-1) fees none
Other expenses 0.19%rr_OtherExpensesOverAssets
Total annual portfolio operating expenses 1.19%rr_ExpensesOverAssets

Example

This example is intended to help you compare the cost of investing in the Portfolio with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the Portfolio for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the Portfolio's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example (USD $)
1 Year
3 Years
5 Years
10 Years
Equity Oriented or Fixed Income Oriented Funds The Emerging Markets Portfolio DPT CLASS
232 492 772 1,570
Expense Example, No Redemption (USD $)
1 Year
3 Years
5 Years
10 Years
Equity Oriented or Fixed Income Oriented Funds The Emerging Markets Portfolio DPT CLASS
176 431 706 1,490

Portfolio turnover

The Portfolio pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Portfolio shares are held in a taxable account. These costs, which are not reflected in annual portfolio operating expenses or in the example, affect the Portfolio's performance. During the most recent fiscal year, the Portfolio's portfolio turnover rate was 27% of the average value of its portfolio.

What are the Portfolio's principal investment strategies?

The Emerging Markets Portfolio is an international fund. The Portfolio generally invests in equity securities of companies organized in, having a majority of their assets in, or deriving a majority of their operating income from, emerging countries. Equity securities include, but are not limited to, common stocks, preferred stocks, convertible securities, certain nontraditional equity securities, and warrants. To the extent that this Portfolio invests in convertible debt securities, those securities will be purchased on the basis of their equity characteristics, and ratings of those securities, if any, will not be an important factor in their selection.

Under normal circumstances, the Portfolio will invest at least 80% of its net assets, plus any borrowings for investment purposes, in investments of emerging market issuers (80% Policy). The Portfolio's 80% Policy may be changed without shareholder approval. However, shareholders will be given notice at least 60 days prior to any such change. Under normal circumstances, the Portfolio will invest at least 40% of its total assets in securities of non-U.S. issuers. This policy is in addition to the 80% Policy.

The Portfolio considers an “emerging country” to be any country that is generally recognized to be an emerging or developing country by the international financial community, including the World Bank and the International Finance Corporation, as well as countries that are classified by the United Nations as developing. In addition, any country that is included in the International Finance Corporation Free Index or MSCI Emerging Markets Index will be considered to be an “emerging country.” There are more than 130 countries that are generally considered to be emerging or developing countries by the international financial community, approximately 40 of which currently have stock markets. Almost every nation in the world is included within this group of developing or emerging countries except the U.S., Canada, Japan, Australia, New Zealand, and nations located in Western Europe.

The Portfolio will focus its investments in those emerging countries where the Portfolio's portfolio managers consider the economies to be developing strongly and where the markets are becoming more sophisticated. Currently, investing in many other emerging countries is not feasible, or may, in the portfolio managers' opinion, involve unacceptable political risks. The portfolio managers believe that investment opportunities may result from an evolving long-term international trend favoring more market-oriented economies, a trend that may particularly benefit certain countries having developing markets. This trend may be facilitated by local or international political, economic, or financial developments that could benefit the capital markets in such countries.

In considering possible emerging countries in which the Portfolio may invest, the portfolio managers will place particular emphasis on factors such as economic conditions (including growth trends, inflation rates, and trade balances), regulatory and currency controls, accounting standards, and political and social conditions. The portfolio managers currently anticipate that the countries in which the Portfolio may invest will include, among others, Argentina, Brazil, Chile, China, Colombia, Croatia, the Czech Republic, Egypt, Estonia, Ghana, Greece, Hong Kong, Hungary, India, Indonesia, Jordan, Kazakhstan, Kenya, Malaysia, Mexico, Morocco, North Korea, Pakistan, Panama, Peru, the Philippines, Poland, Qatar, Romania, Russia, Slovenia, South Africa, South Korea, Sri Lanka, Taiwan, Thailand, Turkey, Ukraine, United Arab Emirates, Venezuela, Vietnam, and Zimbabwe. As markets in other emerging countries develop, the portfolio managers expect to expand and further diversify the countries in which the Portfolio invests.

Although this is not an exclusive list, the portfolio managers consider an emerging country equity security to be one that is issued by a company that exhibits one or more of the following characteristics: (1) its principal securities trading market is in an emerging country, as defined above; (2) while traded in any market, alone or on a consolidated basis, the company derives 50% or more of its annual revenues from either goods produced, sales made or services performed in emerging countries; or (3) it is organized under the laws of, and has a principal office in, an emerging country. The portfolio managers will determine eligibility based on publicly available information and inquiries made of the companies.

Up to 35% of the Portfolio's net assets may be invested in debt securities issued by emerging country companies, and foreign governments, their agencies, instrumentalities, or political subdivisions, all of which may be high yield, high-risk fixed income securities that are below investment grade and are rated lower than BBB- by S&P and lower than Baa3 by Moody's, or similarly rated by another NRSRO. The Portfolio may also invest in zero-coupon bonds. The Portfolio may invest in securities issued in any currency and may hold foreign currency. Securities of issuers within a given country may be denominated in the currency of another country or in multinational currency units, including the euro. For temporary defensive purposes, the Portfolio may invest all or a substantial portion of its assets in high-quality debt instruments.

Currency considerations carry a special risk for a portfolio of international securities. The portfolio managers use a purchasing power parity approach to evaluate currency risk. In this regard, the Portfolio may actively carry on hedging activities, and may invest in forward foreign currency exchange contracts to hedge currency risks associated with the purchase of individual securities denominated in a particular currency.

What are the principal risks of investing in the Portfolio?

Investing in any mutual fund involves the risk that you may lose part or all of the money you invest. Over time, the value of your investment in the Portfolio will increase and decrease according to changes in the value of the securities in its portfolio. Principal risks include:

Risk Definition

Market risk

The risk that all or a majority of the securities in a certain market — such as the stock or bond market — will decline in value because of factors such as adverse political or economic conditions, future expectations, investor confidence, or heavy institutional selling.

Foreign risk

The risk that foreign securities (particularly in emerging markets) may be adversely affected by political instability; changes in currency exchange rates; inefficient markets and higher transaction costs; foreign economic conditions; the imposition of economic or trade sanctions; or inadequate or different regulatory and accounting standards.

Foreign government/
supranational securities risk

The risk that a foreign government or government-related issuer may be unable to make timely payments on its external debt obligations.

Currency risk

The risk that the value of a portfolio's investments may be negatively affected by changes in foreign currency exchange rates.

Derivatives risk

Derivatives contracts, such as options, futures, and swaps, may involve additional expenses (such as the payment of premiums) and are subject to significant loss if a security or a securities index to which a derivatives contract is associated moves in the opposite direction from what the portfolio manager anticipated. Derivatives contracts are also subject to the risk that the counterparty may fail to perform its obligations under the contract due to financial difficulties (such as a bankruptcy or reorganization).

High yield risk

The risk that high yield securities, commonly known as “junk bonds,” are subject to reduced creditworthiness of issuers; increased risk of default and a more limited and less liquid secondary market than higher rated securities; and greater price volatility and risk of loss of income and principal than are higher rated securities because they are rated below investment grade. High yield bonds are sometimes issued by municipalities with less financial strength and therefore less ability to make projected payments on the bonds.

Credit risk

The risk that an issuer of a debt security, including a governmental issuer, or an entity that insures a bond may be unable to make interest payments and repay principal in a timely manner.

Interest rate risk

The risk that securities will decrease in value if interest rates rise. The risk is generally associated with bonds; however, because companies in the real estate sector and smaller companies often borrow money to finance their operations, they may be adversely affected by rising interest rates.

Liquidity risk

The possibility that securities cannot be readily sold within seven days at approximately the price at which a portfolio has valued them.

Investments not guaranteed by
Delaware Management Company
(Manager) or its affiliates

Neither the Manager nor its affiliates noted in this document are authorized deposit-taking institutions for the purposes of the Banking Act 1959 (Commonwealth of Australia). The obligations of these entities do not represent deposits or other liabilities of Macquarie Bank Limited (MBL). MBL does not guarantee or otherwise provide assurance in respect of the obligations of these entities, unless noted otherwise.

How has The Emerging Markets Portfolio performed?

The bar chart and table below provide some indication of the risks of investing in the Portfolio by showing changes in the Portfolio's performance from year to year and by showing how the Portfolio's average annual total returns for the 1-, 5-, and 10-year periods compare with those of a broad measure of market performance. The Portfolio's past performance (before and after taxes) is not necessarily an indication of how it will perform in the future. The returns reflect any expense caps in effect during these periods. The returns would be lower without the expense caps. You may obtain the Portfolio's most recently available month-end performance by calling 800 231-8002 or by visiting our website at delawareinvestments.com/institutional.
Year-by-year total return (The Emerging Markets Portfolio)
Bar Chart

During the periods illustrated in this bar chart, The Emerging Markets Portfolio's highest quarterly return was 32.73% for the quarter ended June 30, 2009 and its lowest quarterly return was -25.15% for the quarter ended Dec. 31, 2008.

Average annual total returns for periods ended December 31, 2015

Average Annual Total Returns Equity Oriented or Fixed Income Oriented Funds The Emerging Markets Portfolio
1 Year
5 Years
10 Years
DPT CLASS
(16.35%) (3.80%) 3.89%
DPT CLASS After Taxes on Distributions
(16.72%) (4.78%) 2.28%
DPT CLASS After Taxes on Distributions and sale of Portfolio shares
(8.70%) (2.34%) 3.74%
MSCI Emerging Markets Index (gross returns)
(14.60%) (4.47%) 3.95%
MSCI Emerging Markets Index (net returns)
(14.92%) (4.81%) 3.61%

Actual after-tax returns depend on the investor's individual tax situation and may differ from the returns shown. After-tax returns are not relevant for shares held in tax-deferred investment vehicles such as employer-sponsored 401(k) plans and individual retirement accounts (IRAs). The after-tax returns shown are calculated using the highest individual federal marginal income tax rates in effect during the Portfolio's lifetime and do not reflect the impact of state and local taxes.

v2.4.1.9
Label Element Value
Risk/Return: rr_RiskReturnAbstract  
Risk/Return, Heading rr_RiskReturnHeading

The Emerging Markets Portfolio

Investment Objective, Heading rr_ObjectiveHeading

What is the Portfolio's investment objective?

Investment Objective, Primary rr_ObjectivePrimaryTextBlock

The Emerging Markets Portfolio seeks long-term capital appreciation.

Expense, Heading rr_ExpenseHeading

What are the Portfolio's fees and expenses?

Expense, Narrative rr_ExpenseNarrativeTextBlock

The table below describes the fees and expenses that you may pay if you buy and hold shares of the Portfolio.

Shareholder Fees, Caption rr_ShareholderFeesCaption

Shareholder fees (fees paid directly from your investment)

Operating Expenses, Caption rr_OperatingExpensesCaption

Annual portfolio operating expenses (expenses that you pay each year as a percentage of the value of your investment)

Portfolio Turnover, Heading rr_PortfolioTurnoverHeading

Portfolio turnover

Portfolio Turnover rr_PortfolioTurnoverTextBlock

The Portfolio pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Portfolio shares are held in a taxable account. These costs, which are not reflected in annual portfolio operating expenses or in the example, affect the Portfolio's performance. During the most recent fiscal year, the Portfolio's portfolio turnover rate was 27% of the average value of its portfolio.

Portfolio Turnover, Rate rr_PortfolioTurnoverRate 27.00%rr_PortfolioTurnoverRate
Expense Example, Heading rr_ExpenseExampleHeading

Example

Expense Example, Narrative rr_ExpenseExampleNarrativeTextBlock

This example is intended to help you compare the cost of investing in the Portfolio with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the Portfolio for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the Portfolio's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Investment Strategy, Heading rr_StrategyHeading

What are the Portfolio's principal investment strategies?

Investment Strategy, Narrative rr_StrategyNarrativeTextBlock

The Emerging Markets Portfolio is an international fund. The Portfolio generally invests in equity securities of companies organized in, having a majority of their assets in, or deriving a majority of their operating income from, emerging countries. Equity securities include, but are not limited to, common stocks, preferred stocks, convertible securities, certain nontraditional equity securities, and warrants. To the extent that this Portfolio invests in convertible debt securities, those securities will be purchased on the basis of their equity characteristics, and ratings of those securities, if any, will not be an important factor in their selection.

Under normal circumstances, the Portfolio will invest at least 80% of its net assets, plus any borrowings for investment purposes, in investments of emerging market issuers (80% Policy). The Portfolio's 80% Policy may be changed without shareholder approval. However, shareholders will be given notice at least 60 days prior to any such change. Under normal circumstances, the Portfolio will invest at least 40% of its total assets in securities of non-U.S. issuers. This policy is in addition to the 80% Policy.

The Portfolio considers an “emerging country” to be any country that is generally recognized to be an emerging or developing country by the international financial community, including the World Bank and the International Finance Corporation, as well as countries that are classified by the United Nations as developing. In addition, any country that is included in the International Finance Corporation Free Index or MSCI Emerging Markets Index will be considered to be an “emerging country.” There are more than 130 countries that are generally considered to be emerging or developing countries by the international financial community, approximately 40 of which currently have stock markets. Almost every nation in the world is included within this group of developing or emerging countries except the U.S., Canada, Japan, Australia, New Zealand, and nations located in Western Europe.

The Portfolio will focus its investments in those emerging countries where the Portfolio's portfolio managers consider the economies to be developing strongly and where the markets are becoming more sophisticated. Currently, investing in many other emerging countries is not feasible, or may, in the portfolio managers' opinion, involve unacceptable political risks. The portfolio managers believe that investment opportunities may result from an evolving long-term international trend favoring more market-oriented economies, a trend that may particularly benefit certain countries having developing markets. This trend may be facilitated by local or international political, economic, or financial developments that could benefit the capital markets in such countries.

In considering possible emerging countries in which the Portfolio may invest, the portfolio managers will place particular emphasis on factors such as economic conditions (including growth trends, inflation rates, and trade balances), regulatory and currency controls, accounting standards, and political and social conditions. The portfolio managers currently anticipate that the countries in which the Portfolio may invest will include, among others, Argentina, Brazil, Chile, China, Colombia, Croatia, the Czech Republic, Egypt, Estonia, Ghana, Greece, Hong Kong, Hungary, India, Indonesia, Jordan, Kazakhstan, Kenya, Malaysia, Mexico, Morocco, North Korea, Pakistan, Panama, Peru, the Philippines, Poland, Qatar, Romania, Russia, Slovenia, South Africa, South Korea, Sri Lanka, Taiwan, Thailand, Turkey, Ukraine, United Arab Emirates, Venezuela, Vietnam, and Zimbabwe. As markets in other emerging countries develop, the portfolio managers expect to expand and further diversify the countries in which the Portfolio invests.

Although this is not an exclusive list, the portfolio managers consider an emerging country equity security to be one that is issued by a company that exhibits one or more of the following characteristics: (1) its principal securities trading market is in an emerging country, as defined above; (2) while traded in any market, alone or on a consolidated basis, the company derives 50% or more of its annual revenues from either goods produced, sales made or services performed in emerging countries; or (3) it is organized under the laws of, and has a principal office in, an emerging country. The portfolio managers will determine eligibility based on publicly available information and inquiries made of the companies.

Up to 35% of the Portfolio's net assets may be invested in debt securities issued by emerging country companies, and foreign governments, their agencies, instrumentalities, or political subdivisions, all of which may be high yield, high-risk fixed income securities that are below investment grade and are rated lower than BBB- by S&P and lower than Baa3 by Moody's, or similarly rated by another NRSRO. The Portfolio may also invest in zero-coupon bonds. The Portfolio may invest in securities issued in any currency and may hold foreign currency. Securities of issuers within a given country may be denominated in the currency of another country or in multinational currency units, including the euro. For temporary defensive purposes, the Portfolio may invest all or a substantial portion of its assets in high-quality debt instruments.

Currency considerations carry a special risk for a portfolio of international securities. The portfolio managers use a purchasing power parity approach to evaluate currency risk. In this regard, the Portfolio may actively carry on hedging activities, and may invest in forward foreign currency exchange contracts to hedge currency risks associated with the purchase of individual securities denominated in a particular currency.

Strategy Portfolio Concentration rr_StrategyPortfolioConcentration
Under normal circumstances, the Portfolio will invest at least 80% of its net assets, plus any borrowings for investment purposes, in investments of emerging market issuers (80% Policy). The Portfolio's 80% Policy may be changed without shareholder approval. However, shareholders will be given notice at least 60 days prior to any such change. Under normal circumstances, the Portfolio will invest at least 40% of its total assets in securities of non-U.S. issuers. This policy is in addition to the 80% Policy.
Risk, Heading rr_RiskHeading

What are the principal risks of investing in the Portfolio?

Risk, Narrative rr_RiskNarrativeTextBlock

Investing in any mutual fund involves the risk that you may lose part or all of the money you invest. Over time, the value of your investment in the Portfolio will increase and decrease according to changes in the value of the securities in its portfolio. Principal risks include:

Risk Definition

Market risk

The risk that all or a majority of the securities in a certain market — such as the stock or bond market — will decline in value because of factors such as adverse political or economic conditions, future expectations, investor confidence, or heavy institutional selling.

Foreign risk

The risk that foreign securities (particularly in emerging markets) may be adversely affected by political instability; changes in currency exchange rates; inefficient markets and higher transaction costs; foreign economic conditions; the imposition of economic or trade sanctions; or inadequate or different regulatory and accounting standards.

Foreign government/
supranational securities risk

The risk that a foreign government or government-related issuer may be unable to make timely payments on its external debt obligations.

Currency risk

The risk that the value of a portfolio's investments may be negatively affected by changes in foreign currency exchange rates.

Derivatives risk

Derivatives contracts, such as options, futures, and swaps, may involve additional expenses (such as the payment of premiums) and are subject to significant loss if a security or a securities index to which a derivatives contract is associated moves in the opposite direction from what the portfolio manager anticipated. Derivatives contracts are also subject to the risk that the counterparty may fail to perform its obligations under the contract due to financial difficulties (such as a bankruptcy or reorganization).

High yield risk

The risk that high yield securities, commonly known as “junk bonds,” are subject to reduced creditworthiness of issuers; increased risk of default and a more limited and less liquid secondary market than higher rated securities; and greater price volatility and risk of loss of income and principal than are higher rated securities because they are rated below investment grade. High yield bonds are sometimes issued by municipalities with less financial strength and therefore less ability to make projected payments on the bonds.

Credit risk

The risk that an issuer of a debt security, including a governmental issuer, or an entity that insures a bond may be unable to make interest payments and repay principal in a timely manner.

Interest rate risk

The risk that securities will decrease in value if interest rates rise. The risk is generally associated with bonds; however, because companies in the real estate sector and smaller companies often borrow money to finance their operations, they may be adversely affected by rising interest rates.

Liquidity risk

The possibility that securities cannot be readily sold within seven days at approximately the price at which a portfolio has valued them.

Investments not guaranteed by
Delaware Management Company
(Manager) or its affiliates

Neither the Manager nor its affiliates noted in this document are authorized deposit-taking institutions for the purposes of the Banking Act 1959 (Commonwealth of Australia). The obligations of these entities do not represent deposits or other liabilities of Macquarie Bank Limited (MBL). MBL does not guarantee or otherwise provide assurance in respect of the obligations of these entities, unless noted otherwise.

Risk, Lose Money rr_RiskLoseMoney
Investing in any mutual fund involves the risk that you may lose part or all of the money you invest.
Risk, Not Insured Depository Institution rr_RiskNotInsuredDepositoryInstitution
Neither the Manager nor its affiliates noted in this document are authorized deposit-taking institutions for the purposes of the Banking Act 1959 (Commonwealth of Australia). The obligations of these entities do not represent deposits or other liabilities of Macquarie Bank Limited (MBL). MBL does not guarantee or otherwise provide assurance in respect of the obligations of these entities, unless noted otherwise.
Bar Chart and Performance Table, Heading rr_BarChartAndPerformanceTableHeading

How has The Emerging Markets Portfolio performed?

Performance, Narrative rr_PerformanceNarrativeTextBlock
The bar chart and table below provide some indication of the risks of investing in the Portfolio by showing changes in the Portfolio's performance from year to year and by showing how the Portfolio's average annual total returns for the 1-, 5-, and 10-year periods compare with those of a broad measure of market performance. The Portfolio's past performance (before and after taxes) is not necessarily an indication of how it will perform in the future. The returns reflect any expense caps in effect during these periods. The returns would be lower without the expense caps. You may obtain the Portfolio's most recently available month-end performance by calling 800 231-8002 or by visiting our website at delawareinvestments.com/institutional.
Performance, Information Illustrates Variability of Returns rr_PerformanceInformationIllustratesVariabilityOfReturns
The bar chart and table below provide some indication of the risks of investing in the Portfolio by showing changes in the Portfolio's performance from year to year and by showing how the Portfolio's average annual total returns for the 1-, 5-, and 10-year periods compare with those of a broad measure of market performance.
Performance Availability Phone rr_PerformanceAvailabilityPhone
800 231-8002
Performance Availability Website Address rr_PerformanceAvailabilityWebSiteAddress
delawareinvestments.com/institutional
Performance Past Does Not Indicate Future rr_PerformancePastDoesNotIndicateFuture
The Portfolio's past performance (before and after taxes) is not necessarily an indication of how it will perform in the future.
Bar Chart, Heading rr_BarChartHeading
Year-by-year total return (The Emerging Markets Portfolio)
Bar Chart, Closing rr_BarChartClosingTextBlock

During the periods illustrated in this bar chart, The Emerging Markets Portfolio's highest quarterly return was 32.73% for the quarter ended June 30, 2009 and its lowest quarterly return was -25.15% for the quarter ended Dec. 31, 2008.

Highest Quarterly Return, Label rr_HighestQuarterlyReturnLabel
highest quarterly return
Highest Quarterly Return, Date rr_BarChartHighestQuarterlyReturnDate Jun. 30, 2009
Highest Quarterly Return rr_BarChartHighestQuarterlyReturn 32.73%rr_BarChartHighestQuarterlyReturn
Lowest Quarterly Return, Label rr_LowestQuarterlyReturnLabel
lowest quarterly return
Lowest Quarterly Return, Date rr_BarChartLowestQuarterlyReturnDate Dec. 31, 2008
Lowest Quarterly Return rr_BarChartLowestQuarterlyReturn (25.15%)rr_BarChartLowestQuarterlyReturn
Performance Table, Heading rr_PerformanceTableHeading

Average annual total returns for periods ended December 31, 2015

Performance Table Uses Highest Federal Rate rr_PerformanceTableUsesHighestFederalRate
The after-tax returns shown are calculated using the highest individual federal marginal income tax rates in effect during the Portfolio's lifetime and do not reflect the impact of state and local taxes.
Performance Table Not Relevant to Tax Deferred rr_PerformanceTableNotRelevantToTaxDeferred
After-tax returns are not relevant for shares held in tax-deferred investment vehicles such as employer-sponsored 401(k) plans and individual retirement accounts (IRAs).
Performance Table, Closing rr_PerformanceTableClosingTextBlock

Actual after-tax returns depend on the investor's individual tax situation and may differ from the returns shown. After-tax returns are not relevant for shares held in tax-deferred investment vehicles such as employer-sponsored 401(k) plans and individual retirement accounts (IRAs). The after-tax returns shown are calculated using the highest individual federal marginal income tax rates in effect during the Portfolio's lifetime and do not reflect the impact of state and local taxes.

MSCI Emerging Markets Index (gross returns)
 
Risk/Return: rr_RiskReturnAbstract  
Index No Deduction for Fees, Expenses, Taxes rr_IndexNoDeductionForFeesExpensesTaxes
reflects no deduction for fees, expenses, or taxes
1 Year rr_AverageAnnualReturnYear01 (14.60%)rr_AverageAnnualReturnYear01
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MSCI Emerging Markets Index (net returns)
 
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DPT CLASS
 
Risk/Return: rr_RiskReturnAbstract  
Maximum sales charge (load) imposed on purchases as apercentage of offering price rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum contingent deferred sales charge (load) as a percentage of original purchase price or redemption price, whichever is lower rr_MaximumDeferredSalesChargeOverOfferingPrice none
Purchase reimbursement fees rr_ExchangeFeeOverRedemption 0.55%rr_ExchangeFeeOverRedemption
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[1]
Redemption reimbursement fees rr_RedemptionFeeOverRedemption 0.55%rr_RedemptionFeeOverRedemption
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[1]
Management fees rr_ManagementFeesOverAssets 1.00%rr_ManagementFeesOverAssets
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Distribution and service (12b-1) fees rr_DistributionAndService12b1FeesOverAssets none
Other expenses rr_OtherExpensesOverAssets 0.19%rr_OtherExpensesOverAssets
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5 Years rr_ExpenseExampleYear05 772rr_ExpenseExampleYear05
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Annual Return 2007 rr_AnnualReturn2007 28.72%rr_AnnualReturn2007
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Annual Return 2008 rr_AnnualReturn2008 (44.88%)rr_AnnualReturn2008
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Annual Return 2009 rr_AnnualReturn2009 68.22%rr_AnnualReturn2009
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Annual Return 2010 rr_AnnualReturn2010 17.59%rr_AnnualReturn2010
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Annual Return 2011 rr_AnnualReturn2011 (11.86%)rr_AnnualReturn2011
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Annual Return 2012 rr_AnnualReturn2012 21.94%rr_AnnualReturn2012
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Annual Return 2013 rr_AnnualReturn2013 (7.58%)rr_AnnualReturn2013
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Annual Return 2014 rr_AnnualReturn2014 (0.86%)rr_AnnualReturn2014
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Annual Return 2015 rr_AnnualReturn2015 (16.35%)rr_AnnualReturn2015
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5 Years rr_AverageAnnualReturnYear05 (3.80%)rr_AverageAnnualReturnYear05
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DPT CLASS | After Taxes on Distributions
 
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DPT CLASS | After Taxes on Distributions and sale of Portfolio shares
 
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[1] The purchase reimbursement fees and redemption reimbursement fees are paid to the Portfolio. These fees are designed to reflect an approximation of the brokerage and other transaction costs associated with the investment of an investor's purchase amount or the disposition of assets to meet redemptions, and to limit the extent to which the Portfolio (and, indirectly, the Portfolio's existing shareholders) would have to bear such costs. In lieu of the reimbursement fees, investors in The Emerging Markets Portfolio may be permitted to utilize alternative purchase and redemption methods designed to accomplish the same economic effect as the reimbursement fees.
v2.4.1.9
Equity Oriented or Fixed Income Oriented Funds | The Emerging Markets Portfolio II

The Emerging Markets Portfolio II

What is the Portfolio's investment objective?

The Emerging Markets Portfolio II seeks long-term capital appreciation.

What are the Portfolio's fees and expenses?

The table below describes the fees and expenses that you may pay if you buy and hold shares of the Portfolio.

Annual portfolio operating expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses
Equity Oriented or Fixed Income Oriented Funds
The Emerging Markets Portfolio II
DPT CLASS
Management fees 1.00%rr_ManagementFeesOverAssets
Distribution and service (12b-1) fees none
Other expenses 0.35%rr_OtherExpensesOverAssets
Total annual portfolio operating expenses 1.35%rr_ExpensesOverAssets
Fee waivers and expense reimbursements [1] (0.15%)rr_FeeWaiverOrReimbursementOverAssets
Total annual portfolio operating expenses after fee waivers and expense reimbursements 1.20%rr_NetExpensesOverAssets
[1] The Portfolio's investment manager, Delaware Management Company (Manager), has contractually agreed to waive all or a portion of its investment advisory fees and/or pay/reimburse expenses (excluding any 12b-1 fees, acquired fund fees and expenses, taxes, interest, expenses, short sale and dividend interest expenses, brokerage fees, certain insurance costs, and nonroutine expenses or costs, including, but not limited to, those relating to reorganizations, litigation, conducting shareholder meetings, and liquidations) in order to prevent total annual portfolio operating expenses from exceeding 1.20% of the Portfolio's average daily net assets from Feb. 26, 2016 through Feb. 28, 2017. These waivers and reimbursements may only be terminated by agreement of the Manager and the Portfolio.

Example

This example is intended to help you compare the cost of investing in the Portfolio with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the Portfolio for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and reflects the Manager's expense waivers and reimbursements for the 1-year contractual period and the total operating expenses without waivers for years 2 through 10. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example (USD $)
1 Year
3 Years
5 Years
10 Years
Equity Oriented or Fixed Income Oriented Funds The Emerging Markets Portfolio II DPT CLASS
122 413 725 1,611

Portfolio turnover

The Portfolio pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Portfolio shares are held in a taxable account. These costs, which are not reflected in annual portfolio operating expenses or in the example, affect the Portfolio's performance. During the most recent fiscal year, the Portfolio's portfolio turnover rate was 8% of the average value of its portfolio.

What are the Portfolio's principal investment strategies?

The Portfolio invests primarily in a broad range of equity securities of companies located in emerging market countries. Emerging market countries include those currently considered to be developing by the World Bank, the United Nations or the countries' governments. These countries typically are located in the Asia-Pacific region, Eastern Europe, the Middle East, Central America, and South America, and Africa. Under normal market conditions, at least 80% of the Portfolio's net assets, plus any borrowings for investment purposes, will be invested in emerging market issuers (80% policy). The Portfolio's 80% policy can be changed without shareholder approval. However, shareholders would be given at least 60 days' notice prior to any such change. The Portfolio may invest in companies of any size and may invest 25% of its assets in the securities of issuers located in the same country.

Although the Portfolio invests primarily in companies from countries considered to be emerging, the Portfolio will also invest in companies that are not in emerging countries: (1) if the portfolio manager believes that the performance of a company or its industry will be influenced by opportunities in the emerging markets; (2) to maintain exposure to industry segments where the portfolio manager believes there are not satisfactory investment opportunities in emerging countries; and (3) if the portfolio manager believes there is the potential for significant benefit to the Portfolio.

The Manager believes that although market price and intrinsic business value are positively correlated in the long run, short-term divergences can emerge. The Portfolio seeks to take advantage of these divergences through a fundamental, bottom-up approach. The Portfolio invests in securities of companies with sustainable franchises when they are trading at a discount to the Manager's intrinsic value estimate for that security.

The Manager defines sustainable franchises as those companies with potential to earn excess returns above their cost of capital over the long run. Sustainability analysis involves identification of a company's source of competitive advantage and the ability of its management to maximize its return potential. The Manager prefers companies with large market opportunities in which to deploy capital, providing opportunities to grow faster than the overall economy.

Intrinsic value assessment is quantitatively determined through a variety of valuation methods including discounted cash flow, replacement cost, private market transaction, and multiples analysis.

What are the principal risks of investing in the Portfolio?

Investing in any mutual fund involves the risk that you may lose part or all of the money you invest. Over time, the value of your investment in the Portfolio will increase and decrease according to changes in the value of the securities in its portfolio. Principal risks include:


Risk Definition

Market risk

The risk that all or a majority of the securities in a certain market — such as the stock or bond market — will decline in value because of factors such as adverse political or economic conditions, future expectations, investor confidence, or heavy institutional selling.

Foreign risk

The risk that foreign securities (particularly in emerging markets) may be adversely affected by political instability; changes in currency exchange rates; inefficient markets and higher transaction costs; foreign economic conditions; the imposition of economic or trade sanctions; or inadequate or different regulatory and accounting standards.

Foreign government/
supranational securities risk

The risk that a foreign government or government related issuer may be unable to make timely payments on its external debt obligations.

Company size risk

The risk that investments in small- and/or medium-sized companies may be more volatile than those of larger companies because of limited financial resources or dependence on narrow product lines.

Currency risk

The risk that the value of a portfolio's investments may be negatively affected by changes in foreign currency exchange rates.

Derivatives risk

Derivatives contracts, such as options, futures, and swaps, may involve additional expenses (such as the payment of premiums) and are subject to significant loss if a security or a securities index to which a derivatives contract is associated moves in the opposite direction from what the portfolio manager anticipated. Derivatives contracts are also subject to the risk that the counterparty may fail to perform its obligations under the contract due to financial difficulties (such as a bankruptcy or reorganization).

Interest rate risk

The risk that securities will decrease in value if interest rates rise. The risk is generally associated with bonds; however, because companies in the real estate sector and smaller companies often borrow money to finance their operations, they may be adversely affected by rising interest rates.

Liquidity risk

The possibility that securities cannot be readily sold within seven days at approximately the price at which a portfolio has valued them.

Investments not guaranteed by
Delaware Management Company
(Manager) or its affiliates

Neither the Manager nor its affiliates noted in this document are authorized deposit-taking institutions for the purposes of the Banking Act 1959 (Commonwealth of Australia). The obligations of these entities do not represent deposits or other liabilities of Macquarie Bank Limited (MBL). MBL does not guarantee or otherwise provide assurance in respect of the obligations of these entities, unless noted otherwise.

How has The Emerging Markets Portfolio II performed?

The bar chart and table below provide some indication of the risks of investing in the Portfolio by showing changes in the Portfolio's performance from year to year and by showing how the Portfolio's average annual total returns for the 1-year, 5-year, and lifetime periods compare with those of a broad measure of market performance. The Portfolio's past performance (before and after taxes) is not necessarily an indication of how it will perform in the future. The returns reflect any expense caps in effect during these periods. The returns would be lower without the expense caps. You may obtain the Portfolio's most recently available month-end performance by calling 800 231-8002 or by visiting our website at delawareinvestments.com/institutional.

Year-by-year total return (The Emerging Markets Portfolio II)

Bar Chart

During the period illustrated in this bar chart, The Emerging Markets Portfolio II's highest quarterly return was 12.68% for the quarter ended Sept. 30, 2013 and its lowest quarterly return was -24.40% for the quarter ended Sept. 30, 2011.

Average annual total returns for periods ended December 31, 2015

Average Annual Total Returns Equity Oriented or Fixed Income Oriented Funds The Emerging Markets Portfolio II
1 Year
5 Years
Lifetime
DPT CLASS
(17.01%) (4.68%) (1.15%)
DPT CLASS After Taxes on Distributions
(17.73%) (5.40%) (1.86%)
DPT CLASS After Taxes on Distributions and sale of Portfolio shares
(8.77%) (3.42%) (0.80%)
MSCI Emerging Markets Index (gross returns)
(14.60%) (4.47%) 0.17%
MSCI Emerging Markets Index (net returns)
(14.92%) (4.81%) (0.18%)

Actual after-tax returns depend on the investor's individual tax situation and may differ from the returns shown. After-tax returns are not relevant for shares held in tax-deferred investment vehicles such as employer-sponsored 401(k) plans and individual retirement accounts (IRAs). The after-tax returns shown are calculated using the highest individual federal marginal income tax rates in effect during the Portfolio's lifetime and do not reflect the impact of state and local taxes.

v2.4.1.9
Label Element Value
Risk/Return: rr_RiskReturnAbstract  
Risk/Return, Heading rr_RiskReturnHeading

The Emerging Markets Portfolio II

Investment Objective, Heading rr_ObjectiveHeading

What is the Portfolio's investment objective?

Investment Objective, Primary rr_ObjectivePrimaryTextBlock

The Emerging Markets Portfolio II seeks long-term capital appreciation.

Expense, Heading rr_ExpenseHeading

What are the Portfolio's fees and expenses?

Expense, Narrative rr_ExpenseNarrativeTextBlock

The table below describes the fees and expenses that you may pay if you buy and hold shares of the Portfolio.

Operating Expenses, Caption rr_OperatingExpensesCaption

Annual portfolio operating expenses (expenses that you pay each year as a percentage of the value of your investment)

Fee Waiver or Reimbursement over Assets, Date of Termination rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination
Feb. 28, 2017
Portfolio Turnover, Heading rr_PortfolioTurnoverHeading

Portfolio turnover

Portfolio Turnover rr_PortfolioTurnoverTextBlock

The Portfolio pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Portfolio shares are held in a taxable account. These costs, which are not reflected in annual portfolio operating expenses or in the example, affect the Portfolio's performance. During the most recent fiscal year, the Portfolio's portfolio turnover rate was 8% of the average value of its portfolio.

Portfolio Turnover, Rate rr_PortfolioTurnoverRate 8.00%rr_PortfolioTurnoverRate
Expense Example, Heading rr_ExpenseExampleHeading

Example

Expense Example, Narrative rr_ExpenseExampleNarrativeTextBlock

This example is intended to help you compare the cost of investing in the Portfolio with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the Portfolio for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and reflects the Manager's expense waivers and reimbursements for the 1-year contractual period and the total operating expenses without waivers for years 2 through 10. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Investment Strategy, Heading rr_StrategyHeading

What are the Portfolio's principal investment strategies?

Investment Strategy, Narrative rr_StrategyNarrativeTextBlock

The Portfolio invests primarily in a broad range of equity securities of companies located in emerging market countries. Emerging market countries include those currently considered to be developing by the World Bank, the United Nations or the countries' governments. These countries typically are located in the Asia-Pacific region, Eastern Europe, the Middle East, Central America, and South America, and Africa. Under normal market conditions, at least 80% of the Portfolio's net assets, plus any borrowings for investment purposes, will be invested in emerging market issuers (80% policy). The Portfolio's 80% policy can be changed without shareholder approval. However, shareholders would be given at least 60 days' notice prior to any such change. The Portfolio may invest in companies of any size and may invest 25% of its assets in the securities of issuers located in the same country.

Although the Portfolio invests primarily in companies from countries considered to be emerging, the Portfolio will also invest in companies that are not in emerging countries: (1) if the portfolio manager believes that the performance of a company or its industry will be influenced by opportunities in the emerging markets; (2) to maintain exposure to industry segments where the portfolio manager believes there are not satisfactory investment opportunities in emerging countries; and (3) if the portfolio manager believes there is the potential for significant benefit to the Portfolio.

The Manager believes that although market price and intrinsic business value are positively correlated in the long run, short-term divergences can emerge. The Portfolio seeks to take advantage of these divergences through a fundamental, bottom-up approach. The Portfolio invests in securities of companies with sustainable franchises when they are trading at a discount to the Manager's intrinsic value estimate for that security.

The Manager defines sustainable franchises as those companies with potential to earn excess returns above their cost of capital over the long run. Sustainability analysis involves identification of a company's source of competitive advantage and the ability of its management to maximize its return potential. The Manager prefers companies with large market opportunities in which to deploy capital, providing opportunities to grow faster than the overall economy.

Intrinsic value assessment is quantitatively determined through a variety of valuation methods including discounted cash flow, replacement cost, private market transaction, and multiples analysis.

Strategy Portfolio Concentration rr_StrategyPortfolioConcentration
Under normal market conditions, at least 80% of the Portfolio's net assets, plus any borrowings for investment purposes, will be invested in emerging market issuers (80% policy). The Portfolio's 80% policy can be changed without shareholder approval. However, shareholders would be given at least 60 days' notice prior to any such change.
Risk, Heading rr_RiskHeading

What are the principal risks of investing in the Portfolio?

Risk, Narrative rr_RiskNarrativeTextBlock

Investing in any mutual fund involves the risk that you may lose part or all of the money you invest. Over time, the value of your investment in the Portfolio will increase and decrease according to changes in the value of the securities in its portfolio. Principal risks include:


Risk Definition

Market risk

The risk that all or a majority of the securities in a certain market — such as the stock or bond market — will decline in value because of factors such as adverse political or economic conditions, future expectations, investor confidence, or heavy institutional selling.

Foreign risk

The risk that foreign securities (particularly in emerging markets) may be adversely affected by political instability; changes in currency exchange rates; inefficient markets and higher transaction costs; foreign economic conditions; the imposition of economic or trade sanctions; or inadequate or different regulatory and accounting standards.

Foreign government/
supranational securities risk

The risk that a foreign government or government related issuer may be unable to make timely payments on its external debt obligations.

Company size risk

The risk that investments in small- and/or medium-sized companies may be more volatile than those of larger companies because of limited financial resources or dependence on narrow product lines.

Currency risk

The risk that the value of a portfolio's investments may be negatively affected by changes in foreign currency exchange rates.

Derivatives risk

Derivatives contracts, such as options, futures, and swaps, may involve additional expenses (such as the payment of premiums) and are subject to significant loss if a security or a securities index to which a derivatives contract is associated moves in the opposite direction from what the portfolio manager anticipated. Derivatives contracts are also subject to the risk that the counterparty may fail to perform its obligations under the contract due to financial difficulties (such as a bankruptcy or reorganization).

Interest rate risk

The risk that securities will decrease in value if interest rates rise. The risk is generally associated with bonds; however, because companies in the real estate sector and smaller companies often borrow money to finance their operations, they may be adversely affected by rising interest rates.

Liquidity risk

The possibility that securities cannot be readily sold within seven days at approximately the price at which a portfolio has valued them.

Investments not guaranteed by
Delaware Management Company
(Manager) or its affiliates

Neither the Manager nor its affiliates noted in this document are authorized deposit-taking institutions for the purposes of the Banking Act 1959 (Commonwealth of Australia). The obligations of these entities do not represent deposits or other liabilities of Macquarie Bank Limited (MBL). MBL does not guarantee or otherwise provide assurance in respect of the obligations of these entities, unless noted otherwise.

Risk, Lose Money rr_RiskLoseMoney
Investing in any mutual fund involves the risk that you may lose part or all of the money you invest.
Risk, Not Insured Depository Institution rr_RiskNotInsuredDepositoryInstitution
Neither the Manager nor its affiliates noted in this document are authorized deposit-taking institutions for the purposes of the Banking Act 1959 (Commonwealth of Australia). The obligations of these entities do not represent deposits or other liabilities of Macquarie Bank Limited (MBL). MBL does not guarantee or otherwise provide assurance in respect of the obligations of these entities, unless noted otherwise.
Bar Chart and Performance Table, Heading rr_BarChartAndPerformanceTableHeading

How has The Emerging Markets Portfolio II performed?

Performance, Narrative rr_PerformanceNarrativeTextBlock

The bar chart and table below provide some indication of the risks of investing in the Portfolio by showing changes in the Portfolio's performance from year to year and by showing how the Portfolio's average annual total returns for the 1-year, 5-year, and lifetime periods compare with those of a broad measure of market performance. The Portfolio's past performance (before and after taxes) is not necessarily an indication of how it will perform in the future. The returns reflect any expense caps in effect during these periods. The returns would be lower without the expense caps. You may obtain the Portfolio's most recently available month-end performance by calling 800 231-8002 or by visiting our website at delawareinvestments.com/institutional.

Performance, Information Illustrates Variability of Returns rr_PerformanceInformationIllustratesVariabilityOfReturns
The bar chart and table below provide some indication of the risks of investing in the Portfolio by showing changes in the Portfolio's performance from year to year and by showing how the Portfolio's average annual total returns for the 1-year, 5-year, and lifetime periods compare with those of a broad measure of market performance.
Performance Availability Phone rr_PerformanceAvailabilityPhone
800 231-8002
Performance Availability Website Address rr_PerformanceAvailabilityWebSiteAddress
delawareinvestments.com/institutional
Performance Past Does Not Indicate Future rr_PerformancePastDoesNotIndicateFuture
The Portfolio's past performance (before and after taxes) is not necessarily an indication of how it will perform in the future.
Bar Chart, Heading rr_BarChartHeading

Year-by-year total return (The Emerging Markets Portfolio II)

Bar Chart, Closing rr_BarChartClosingTextBlock

During the period illustrated in this bar chart, The Emerging Markets Portfolio II's highest quarterly return was 12.68% for the quarter ended Sept. 30, 2013 and its lowest quarterly return was -24.40% for the quarter ended Sept. 30, 2011.

Highest Quarterly Return, Label rr_HighestQuarterlyReturnLabel
highest quarterly return
Highest Quarterly Return, Date rr_BarChartHighestQuarterlyReturnDate Sep. 30, 2013
Highest Quarterly Return rr_BarChartHighestQuarterlyReturn 12.68%rr_BarChartHighestQuarterlyReturn
Lowest Quarterly Return, Label rr_LowestQuarterlyReturnLabel
lowest quarterly return
Lowest Quarterly Return, Date rr_BarChartLowestQuarterlyReturnDate Sep. 30, 2011
Lowest Quarterly Return rr_BarChartLowestQuarterlyReturn (24.40%)rr_BarChartLowestQuarterlyReturn
Performance Table, Heading rr_PerformanceTableHeading

Average annual total returns for periods ended December 31, 2015

Performance Table Uses Highest Federal Rate rr_PerformanceTableUsesHighestFederalRate
The after-tax returns shown are calculated using the highest individual federal marginal income tax rates in effect during the Portfolio's lifetime and do not reflect the impact of state and local taxes.
Performance Table Not Relevant to Tax Deferred rr_PerformanceTableNotRelevantToTaxDeferred
After-tax returns are not relevant for shares held in tax-deferred investment vehicles such as employer-sponsored 401(k) plans and individual retirement accounts (IRAs).
Performance Table, Closing rr_PerformanceTableClosingTextBlock

Actual after-tax returns depend on the investor's individual tax situation and may differ from the returns shown. After-tax returns are not relevant for shares held in tax-deferred investment vehicles such as employer-sponsored 401(k) plans and individual retirement accounts (IRAs). The after-tax returns shown are calculated using the highest individual federal marginal income tax rates in effect during the Portfolio's lifetime and do not reflect the impact of state and local taxes.

MSCI Emerging Markets Index (gross returns)
 
Risk/Return: rr_RiskReturnAbstract  
Index No Deduction for Fees, Expenses, Taxes rr_IndexNoDeductionForFeesExpensesTaxes
reflects no deduction for fees, expenses, or taxes
1 Year rr_AverageAnnualReturnYear01 (14.60%)rr_AverageAnnualReturnYear01
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Risk/Return: rr_RiskReturnAbstract  
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DPT CLASS
 
Risk/Return: rr_RiskReturnAbstract  
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[1]
Total annual portfolio operating expenses after fee waivers and expense reimbursements rr_NetExpensesOverAssets 1.20%rr_NetExpensesOverAssets
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DPT CLASS | After Taxes on Distributions
 
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DPT CLASS | After Taxes on Distributions and sale of Portfolio shares
 
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[1] The Portfolio's investment manager, Delaware Management Company (Manager), has contractually agreed to waive all or a portion of its investment advisory fees and/or pay/reimburse expenses (excluding any 12b-1 fees, acquired fund fees and expenses, taxes, interest, expenses, short sale and dividend interest expenses, brokerage fees, certain insurance costs, and nonroutine expenses or costs, including, but not limited to, those relating to reorganizations, litigation, conducting shareholder meetings, and liquidations) in order to prevent total annual portfolio operating expenses from exceeding 1.20% of the Portfolio's average daily net assets from Feb. 26, 2016 through Feb. 28, 2017. These waivers and reimbursements may only be terminated by agreement of the Manager and the Portfolio.
v2.4.1.9
Equity Oriented or Fixed Income Oriented Funds | The High-Yield Bond Portfolio

The High-Yield Bond Portfolio

What is the Portfolio's investment objective?

The High-Yield Bond Portfolio seeks high total return.

What are the Portfolio's fees and expenses?

The table below describes the fees and expenses that you may pay if you buy and hold shares of the Portfolio.

Annual portfolio operating expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses
Equity Oriented or Fixed Income Oriented Funds
The High-Yield Bond Portfolio
DPT CLASS
Management fees 0.45%rr_ManagementFeesOverAssets
Distribution and service (12b-1) fees none
Other expenses 0.11%rr_OtherExpensesOverAssets
Total annual portfolio operating expenses 0.56%rr_ExpensesOverAssets
Fee waivers and expense reimbursements [1] none
Total annual portfolio operating expenses after fee waivers and expense reimbursements 0.56%rr_NetExpensesOverAssets
[1] The Portfolio's investment manager, Delaware Management Company (Manager), has contractually agreed to waive all or a portion of its investment advisory fees and/or pay/ reimburse expenses (excluding any 12b-1 fees, acquired fund fees and expenses, taxes, interest, expenses, short sale and dividend interest expenses, brokerage fees, certain insurance costs, and nonroutine expenses or costs, including, but not limited to, those relating to reorganizations, litigation, conducting shareholder meetings, and liquidations) in order to prevent total annual portfolio operating expenses from exceeding 0.59% of the Portfolio's average daily net assets from Feb. 26, 2016 through Feb. 28, 2017. These waivers and reimbursements may only be terminated by agreement of the Manager and the Portfolio.

Example

This example is intended to help you compare the cost of investing in the Portfolio with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the Portfolio for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and reflects the Manager's expense waivers and reimbursements for the 1-year contractual period and the total operating expenses without waivers for years 2 through 10. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example (USD $)
1 Year
3 Years
5 Years
10 Years
Equity Oriented or Fixed Income Oriented Funds The High-Yield Bond Portfolio DPT CLASS
57 179 313 701

Portfolio turnover

The Portfolio pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Portfolio shares are held in a taxable account. These costs, which are not reflected in annual portfolio operating expenses or in the example, affect the Portfolio's performance. During the most recent fiscal year, the Portfolio's portfolio turnover rate was 84% of the average value of its portfolio.

What are the Portfolio's principal investment strategies?

The Portfolio will primarily invest its assets at the time of purchase in: (1) below investment grade corporate bonds rated BB or lower by S&P or similarly rated by another NRSRO; (2) securities issued or guaranteed by the U.S. government, its agencies or instrumentalities; or (3) commercial paper of companies rated A-1 or A-2 by S&P or rated P-1 or P-2 by Moody's or that may be unrated but considered to be of comparable quality. Of these categories of securities, the Manager anticipates investing primarily in corporate bonds. The Portfolio may also invest in income-producing securities, including common stocks and preferred stocks, some of which may have convertible features or attached warrants and that may be speculative. The Portfolio may invest up to 40% of its net assets in foreign securities; however, the Portfolio's total non-U.S.-dollar currency exposure will be limited, in the aggregate, to no more than 25% of the Portfolio's net assets, and investments in emerging market securities will be limited to 20% of the Portfolio's net assets. The Portfolio may hold cash or invest in short-term debt securities and other money market instruments when, in the Manager's opinion, such holdings are prudent given then prevailing market conditions. Except when the Manager believes a temporary defensive approach is appropriate, the Portfolio normally will not hold more than 5% of its total assets in cash or such short-term investments.

Under normal circumstances, the Portfolio will invest at least 80% of its net assets, plus any borrowings for investment purposes, in high yield, fixed income securities (80% Policy). The Portfolio's 80% Policy may be changed without shareholder approval. However, shareholders will be given notice at least 60 days prior to any such change.

High yield, fixed income securities, or high yield bonds, are generally considered to be those rated lower than BBB- by S&P and lower than Baa3 by Moody's, or similarly rated by another NRSRO. The Portfolio will generally focus its investments on bonds in the BB/Ba or B/B ratings categories and in unrated bonds of similar quality.

From time to time, the Portfolio may acquire zero-coupon bonds and, to a lesser extent, pay-in-kind (PIK) bonds; however, the Portfolio generally does not purchase a substantial number of these securities.

With respect to U.S. government securities, the Portfolio may invest only in securities issued or guaranteed as to the payment of principal and interest by the U.S. government, and those of its agencies or instrumentalities that are backed by the full faith and credit of the U.S.

The Manager does not normally intend to respond to short-term market fluctuations or to acquire securities for the purpose of short-term trading; however, the Manager may take advantage of short-term opportunities that are consistent with the Portfolio's investment objective.

What are the principal risks of investing in the Portfolio?

Investing in any mutual fund involves the risk that you may lose part or all of the money you invest. Over time, the value of your investment in the Portfolio will increase and decrease according to changes in the value of the securities in its portfolio. Principal risks include:

Risk Definition

Market risk

The risk that all or a majority of the securities in a certain market — such as the stock or bond market — will decline in value because of factors such as adverse political or economic conditions, future expectations, investor confidence, or heavy institutional selling.

High yield risk

The risk that high yield securities, commonly known as “junk bonds,” are subject to reduced creditworthiness of issuers; increased risk of default and a more limited and less liquid secondary market than higher rated securities; and greater price volatility and risk of loss of income and principal than are higher rated securities because they are rated below investment grade. High yield bonds are sometimes issued by municipalities with less financial strength and therefore less ability to make projected debt payments on the bonds.

Credit risk

The risk that an issuer of a debt security, including a governmental issuer, or an entity that insures a bond may be unable to make interest payments and repay principal in a timely manner.

Interest rate risk

The risk that securities will decrease in value if interest rates rise. The risk is generally associated with bonds; however, because companies in the real estate sector and smaller companies often borrow money to finance their operations, they may be adversely affected by rising interest rates.

Bank loans and other direct
indebtedness risk

The risk that the portfolio will not receive payment of principal, interest, and other amounts due in connection with these investments and will depend primarily on the financial condition of the borrower and the lending institution.

Foreign risk

The risk that foreign securities (particularly in emerging markets) may be adversely affected by political instability; changes in currency exchange rates; inefficient markets and higher transaction costs; foreign economic conditions; the imposition of economic or trade sanctions; or inadequate or different regulatory and accounting standards.

Currency risk

The risk that the value of a portfolio's investments may be negatively affected by changes in foreign currency exchange rates.

Foreign government/
supranational securities risk

The risk that a foreign government or government-related issuer may be unable to make timely payments on its external debt obligations.

Derivatives risk

Derivatives contracts, such as options, futures, and swaps, may involve additional expenses (such as the payment of premiums) and are subject to significant loss if a security or a securities index to which a derivatives contract is associated moves in the opposite direction from what the portfolio manager anticipated. Derivatives contracts are also subject to the risk that the counterparty may fail to perform its obligations under the contract due to financial difficulties (such as a bankruptcy or reorganization).

Liquidity risk

The possibility that securities cannot be readily sold within seven days at approximately the price at which a portfolio has valued them.

Investments not guaranteed by
Delaware Management Company
(Manager) or its affiliates

Neither the Manager nor its affiliates noted in this document are authorized deposit-taking institutions for the purposes of the Banking Act 1959 (Commonwealth of Australia). The obligations of these entities do not represent deposits or other liabilities of Macquarie Bank Limited (MBL). MBL does not guarantee or otherwise provide assurance in respect of the obligations of these entities, unless noted otherwise.

How has The High-Yield Bond Portfolio performed?

The bar chart and table below provide some indication of the risks of investing in the Portfolio by showing changes in the Portfolio's performance from year to year and by showing how the Portfolio's average annual total returns for the 1-, 5-, and 10-year periods compare with those of a broad measure of market performance. The Portfolio's past performance (before and after taxes) is not necessarily an indication of how it will perform in the future. The returns reflect any expense caps in effect during these periods. The returns would be lower without the expense caps. You may obtain the Portfolio's most recently available month-end performance by calling 800 231-8002 or by visiting our website at delawareinvestments.com/institutional.

Year-by-year total return (The High-Yield Bond Portfolio)

Bar Chart

During the periods illustrated in this bar chart, The High-Yield Bond Portfolio's highest quarterly return was 21.06% for the quarter ended June 30, 2009 and its lowest quarterly return was -17.17% for the quarter ended Dec. 31, 2008.

Average annual total returns for periods ended December 31, 2015

Average Annual Total Returns Equity Oriented or Fixed Income Oriented Funds The High-Yield Bond Portfolio
1 Year
5 Years
10 Years
DPT CLASS
(4.98%) 4.89% 7.15%
DPT CLASS After Taxes on Distributions
(7.05%) 2.40% 4.32%
DPT CLASS After Taxes on Distributions and sale of Portfolio shares
(2.82%) 2.79% 4.42%
BofA Merrill Lynch U.S. High Yield Constrained Index
(4.61%) 4.84% 6.81%

Actual after-tax returns depend on the investor's individual tax situation and may differ from the returns shown. After-tax returns are not relevant for shares held in tax-deferred investment vehicles such as employer-sponsored 401(k) plans and individual retirement accounts (IRAs). The after-tax returns shown are calculated using the highest individual federal marginal income tax rates in effect during the Portfolio's lifetime and do not reflect the impact of state and local taxes.

v2.4.1.9
Label Element Value
Risk/Return: rr_RiskReturnAbstract  
Risk/Return, Heading rr_RiskReturnHeading

The High-Yield Bond Portfolio

Investment Objective, Heading rr_ObjectiveHeading

What is the Portfolio's investment objective?

Investment Objective, Primary rr_ObjectivePrimaryTextBlock

The High-Yield Bond Portfolio seeks high total return.

Expense, Heading rr_ExpenseHeading

What are the Portfolio's fees and expenses?

Expense, Narrative rr_ExpenseNarrativeTextBlock

The table below describes the fees and expenses that you may pay if you buy and hold shares of the Portfolio.

Operating Expenses, Caption rr_OperatingExpensesCaption

Annual portfolio operating expenses (expenses that you pay each year as a percentage of the value of your investment)

Fee Waiver or Reimbursement over Assets, Date of Termination rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination
Feb. 28, 2017
Portfolio Turnover, Heading rr_PortfolioTurnoverHeading

Portfolio turnover

Portfolio Turnover rr_PortfolioTurnoverTextBlock

The Portfolio pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Portfolio shares are held in a taxable account. These costs, which are not reflected in annual portfolio operating expenses or in the example, affect the Portfolio's performance. During the most recent fiscal year, the Portfolio's portfolio turnover rate was 84% of the average value of its portfolio.

Portfolio Turnover, Rate rr_PortfolioTurnoverRate 84.00%rr_PortfolioTurnoverRate
Expense Example, Heading rr_ExpenseExampleHeading

Example

Expense Example, Narrative rr_ExpenseExampleNarrativeTextBlock

This example is intended to help you compare the cost of investing in the Portfolio with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the Portfolio for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and reflects the Manager's expense waivers and reimbursements for the 1-year contractual period and the total operating expenses without waivers for years 2 through 10. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Investment Strategy, Heading rr_StrategyHeading

What are the Portfolio's principal investment strategies?

Investment Strategy, Narrative rr_StrategyNarrativeTextBlock

The Portfolio will primarily invest its assets at the time of purchase in: (1) below investment grade corporate bonds rated BB or lower by S&P or similarly rated by another NRSRO; (2) securities issued or guaranteed by the U.S. government, its agencies or instrumentalities; or (3) commercial paper of companies rated A-1 or A-2 by S&P or rated P-1 or P-2 by Moody's or that may be unrated but considered to be of comparable quality. Of these categories of securities, the Manager anticipates investing primarily in corporate bonds. The Portfolio may also invest in income-producing securities, including common stocks and preferred stocks, some of which may have convertible features or attached warrants and that may be speculative. The Portfolio may invest up to 40% of its net assets in foreign securities; however, the Portfolio's total non-U.S.-dollar currency exposure will be limited, in the aggregate, to no more than 25% of the Portfolio's net assets, and investments in emerging market securities will be limited to 20% of the Portfolio's net assets. The Portfolio may hold cash or invest in short-term debt securities and other money market instruments when, in the Manager's opinion, such holdings are prudent given then prevailing market conditions. Except when the Manager believes a temporary defensive approach is appropriate, the Portfolio normally will not hold more than 5% of its total assets in cash or such short-term investments.

Under normal circumstances, the Portfolio will invest at least 80% of its net assets, plus any borrowings for investment purposes, in high yield, fixed income securities (80% Policy). The Portfolio's 80% Policy may be changed without shareholder approval. However, shareholders will be given notice at least 60 days prior to any such change.

High yield, fixed income securities, or high yield bonds, are generally considered to be those rated lower than BBB- by S&P and lower than Baa3 by Moody's, or similarly rated by another NRSRO. The Portfolio will generally focus its investments on bonds in the BB/Ba or B/B ratings categories and in unrated bonds of similar quality.

From time to time, the Portfolio may acquire zero-coupon bonds and, to a lesser extent, pay-in-kind (PIK) bonds; however, the Portfolio generally does not purchase a substantial number of these securities.

With respect to U.S. government securities, the Portfolio may invest only in securities issued or guaranteed as to the payment of principal and interest by the U.S. government, and those of its agencies or instrumentalities that are backed by the full faith and credit of the U.S.

The Manager does not normally intend to respond to short-term market fluctuations or to acquire securities for the purpose of short-term trading; however, the Manager may take advantage of short-term opportunities that are consistent with the Portfolio's investment objective.

Strategy Portfolio Concentration rr_StrategyPortfolioConcentration
Under normal circumstances, the Portfolio will invest at least 80% of its net assets, plus any borrowings for investment purposes, in high yield, fixed income securities (80% Policy). The Portfolio's 80% Policy may be changed without shareholder approval. However, shareholders will be given notice at least 60 days prior to any such change.
Risk, Heading rr_RiskHeading

What are the principal risks of investing in the Portfolio?

Risk, Narrative rr_RiskNarrativeTextBlock

Investing in any mutual fund involves the risk that you may lose part or all of the money you invest. Over time, the value of your investment in the Portfolio will increase and decrease according to changes in the value of the securities in its portfolio. Principal risks include:

Risk Definition

Market risk

The risk that all or a majority of the securities in a certain market — such as the stock or bond market — will decline in value because of factors such as adverse political or economic conditions, future expectations, investor confidence, or heavy institutional selling.

High yield risk

The risk that high yield securities, commonly known as “junk bonds,” are subject to reduced creditworthiness of issuers; increased risk of default and a more limited and less liquid secondary market than higher rated securities; and greater price volatility and risk of loss of income and principal than are higher rated securities because they are rated below investment grade. High yield bonds are sometimes issued by municipalities with less financial strength and therefore less ability to make projected debt payments on the bonds.

Credit risk

The risk that an issuer of a debt security, including a governmental issuer, or an entity that insures a bond may be unable to make interest payments and repay principal in a timely manner.

Interest rate risk

The risk that securities will decrease in value if interest rates rise. The risk is generally associated with bonds; however, because companies in the real estate sector and smaller companies often borrow money to finance their operations, they may be adversely affected by rising interest rates.

Bank loans and other direct
indebtedness risk

The risk that the portfolio will not receive payment of principal, interest, and other amounts due in connection with these investments and will depend primarily on the financial condition of the borrower and the lending institution.

Foreign risk

The risk that foreign securities (particularly in emerging markets) may be adversely affected by political instability; changes in currency exchange rates; inefficient markets and higher transaction costs; foreign economic conditions; the imposition of economic or trade sanctions; or inadequate or different regulatory and accounting standards.

Currency risk

The risk that the value of a portfolio's investments may be negatively affected by changes in foreign currency exchange rates.

Foreign government/
supranational securities risk

The risk that a foreign government or government-related issuer may be unable to make timely payments on its external debt obligations.

Derivatives risk

Derivatives contracts, such as options, futures, and swaps, may involve additional expenses (such as the payment of premiums) and are subject to significant loss if a security or a securities index to which a derivatives contract is associated moves in the opposite direction from what the portfolio manager anticipated. Derivatives contracts are also subject to the risk that the counterparty may fail to perform its obligations under the contract due to financial difficulties (such as a bankruptcy or reorganization).

Liquidity risk

The possibility that securities cannot be readily sold within seven days at approximately the price at which a portfolio has valued them.

Investments not guaranteed by
Delaware Management Company
(Manager) or its affiliates

Neither the Manager nor its affiliates noted in this document are authorized deposit-taking institutions for the purposes of the Banking Act 1959 (Commonwealth of Australia). The obligations of these entities do not represent deposits or other liabilities of Macquarie Bank Limited (MBL). MBL does not guarantee or otherwise provide assurance in respect of the obligations of these entities, unless noted otherwise.

Risk, Lose Money rr_RiskLoseMoney
Investing in any mutual fund involves the risk that you may lose part or all of the money you invest.
Risk, Not Insured Depository Institution rr_RiskNotInsuredDepositoryInstitution
Neither the Manager nor its affiliates noted in this document are authorized deposit-taking institutions for the purposes of the Banking Act 1959 (Commonwealth of Australia). The obligations of these entities do not represent deposits or other liabilities of Macquarie Bank Limited (MBL). MBL does not guarantee or otherwise provide assurance in respect of the obligations of these entities, unless noted otherwise.
Bar Chart and Performance Table, Heading rr_BarChartAndPerformanceTableHeading

How has The High-Yield Bond Portfolio performed?

Performance, Narrative rr_PerformanceNarrativeTextBlock

The bar chart and table below provide some indication of the risks of investing in the Portfolio by showing changes in the Portfolio's performance from year to year and by showing how the Portfolio's average annual total returns for the 1-, 5-, and 10-year periods compare with those of a broad measure of market performance. The Portfolio's past performance (before and after taxes) is not necessarily an indication of how it will perform in the future. The returns reflect any expense caps in effect during these periods. The returns would be lower without the expense caps. You may obtain the Portfolio's most recently available month-end performance by calling 800 231-8002 or by visiting our website at delawareinvestments.com/institutional.

Performance, Information Illustrates Variability of Returns rr_PerformanceInformationIllustratesVariabilityOfReturns
The bar chart and table below provide some indication of the risks of investing in the Portfolio by showing changes in the Portfolio's performance from year to year and by showing how the Portfolio's average annual total returns for the 1-, 5-, and 10-year periods compare with those of a broad measure of market performance.
Performance Availability Phone rr_PerformanceAvailabilityPhone
800 231-8002
Performance Availability Website Address rr_PerformanceAvailabilityWebSiteAddress
delawareinvestments.com/institutional
Performance Past Does Not Indicate Future rr_PerformancePastDoesNotIndicateFuture
The Portfolio's past performance (before and after taxes) is not necessarily an indication of how it will perform in the future.
Bar Chart, Heading rr_BarChartHeading

Year-by-year total return (The High-Yield Bond Portfolio)

Bar Chart, Closing rr_BarChartClosingTextBlock

During the periods illustrated in this bar chart, The High-Yield Bond Portfolio's highest quarterly return was 21.06% for the quarter ended June 30, 2009 and its lowest quarterly return was -17.17% for the quarter ended Dec. 31, 2008.

Highest Quarterly Return, Label rr_HighestQuarterlyReturnLabel
highest quarterly return
Highest Quarterly Return, Date rr_BarChartHighestQuarterlyReturnDate Jun. 30, 2009
Highest Quarterly Return rr_BarChartHighestQuarterlyReturn 21.06%rr_BarChartHighestQuarterlyReturn
Lowest Quarterly Return, Label rr_LowestQuarterlyReturnLabel
lowest quarterly return
Lowest Quarterly Return, Date rr_BarChartLowestQuarterlyReturnDate Dec. 31, 2008
Lowest Quarterly Return rr_BarChartLowestQuarterlyReturn (17.17%)rr_BarChartLowestQuarterlyReturn
Performance Table, Heading rr_PerformanceTableHeading

Average annual total returns for periods ended December 31, 2015

Performance Table Uses Highest Federal Rate rr_PerformanceTableUsesHighestFederalRate
The after-tax returns shown are calculated using the highest individual federal marginal income tax rates in effect during the Portfolio's lifetime and do not reflect the impact of state and local taxes.
Performance Table Not Relevant to Tax Deferred rr_PerformanceTableNotRelevantToTaxDeferred
After-tax returns are not relevant for shares held in tax-deferred investment vehicles such as employer-sponsored 401(k) plans and individual retirement accounts (IRAs).
Performance Table, Closing rr_PerformanceTableClosingTextBlock

Actual after-tax returns depend on the investor's individual tax situation and may differ from the returns shown. After-tax returns are not relevant for shares held in tax-deferred investment vehicles such as employer-sponsored 401(k) plans and individual retirement accounts (IRAs). The after-tax returns shown are calculated using the highest individual federal marginal income tax rates in effect during the Portfolio's lifetime and do not reflect the impact of state and local taxes.

BofA Merrill Lynch U.S. High Yield Constrained Index
 
Risk/Return: rr_RiskReturnAbstract  
Index No Deduction for Fees, Expenses, Taxes rr_IndexNoDeductionForFeesExpensesTaxes
reflects no deduction for fees, expenses, or taxes
1 Year rr_AverageAnnualReturnYear01 (4.61%)rr_AverageAnnualReturnYear01
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DPT CLASS
 
Risk/Return: rr_RiskReturnAbstract  
Management fees rr_ManagementFeesOverAssets 0.45%rr_ManagementFeesOverAssets
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Other expenses rr_OtherExpensesOverAssets 0.11%rr_OtherExpensesOverAssets
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Fee waivers and expense reimbursements rr_FeeWaiverOrReimbursementOverAssets none [1]
Total annual portfolio operating expenses after fee waivers and expense reimbursements rr_NetExpensesOverAssets 0.56%rr_NetExpensesOverAssets
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DPT CLASS | After Taxes on Distributions
 
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[1] The Portfolio's investment manager, Delaware Management Company (Manager), has contractually agreed to waive all or a portion of its investment advisory fees and/or pay/ reimburse expenses (excluding any 12b-1 fees, acquired fund fees and expenses, taxes, interest, expenses, short sale and dividend interest expenses, brokerage fees, certain insurance costs, and nonroutine expenses or costs, including, but not limited to, those relating to reorganizations, litigation, conducting shareholder meetings, and liquidations) in order to prevent total annual portfolio operating expenses from exceeding 0.59% of the Portfolio's average daily net assets from Feb. 26, 2016 through Feb. 28, 2017. These waivers and reimbursements may only be terminated by agreement of the Manager and the Portfolio.
v2.4.1.9
Equity Oriented or Fixed Income Oriented Funds | The Core Plus Fixed Income Portfolio

The Core Plus Fixed Income Portfolio

What is the Portfolio's investment objective?

The Core Plus Fixed Income Portfolio seeks maximum long-term total return, consistent with reasonable risk.

What are the Portfolio's fees and expenses?

The table below describes the fees and expenses that you may pay if you buy and hold shares of the Portfolio.

Annual portfolio operating expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses
Equity Oriented or Fixed Income Oriented Funds
The Core Plus Fixed Income Portfolio
DPT CLASS
Management fees 0.43%rr_ManagementFeesOverAssets
Distribution and service (12b-1) fees none
Other expenses 0.17%rr_OtherExpensesOverAssets
Total annual portfolio operating expenses 0.60%rr_ExpensesOverAssets
Fee waivers and expense reimbursements [1] (0.15%)rr_FeeWaiverOrReimbursementOverAssets
Total annual portfolio operating expenses after fee waivers and expense reimbursements 0.45%rr_NetExpensesOverAssets
[1] The Portfolio's investment manager, Delaware Management Company (Manager), has contractually agreed to waive all or a portion of its investment advisory fees and/or pay/reimburse expenses (excluding any 12b-1 fees, acquired fund fees and expenses, taxes, interest, expenses, short sale and dividend interest expenses, brokerage fees, certain insurance costs, and nonroutine expenses or costs, including, but not limited to, those relating to reorganizations, litigation, conducting shareholder meetings, and liquidations) in order to prevent total annual portfolio operating expenses from exceeding 0.45% of the Portfolio's average daily net assets from Feb. 26, 2016 through Feb. 28, 2017. These waivers and reimbursements may only be terminated by agreement of the Manager and the Portfolio.
Example
This example is intended to help you compare the cost of investing in the Portfolio with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the Portfolio for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and reflects the Manager's expense waivers and reimbursements for the 1-year contractual period and the total operating expenses without waivers for years 2 through 10. Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Expense Example (USD $)
1 Year
3 Years
5 Years
10 Years
Equity Oriented or Fixed Income Oriented Funds The Core Plus Fixed Income Portfolio DPT CLASS
46 177 320 736

Portfolio turnover

The Portfolio pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Portfolio shares are held in a taxable account. These costs, which are not reflected in annual portfolio operating expenses or in the example, affect the Portfolio's performance. During the most recent fiscal year, the Portfolio's portfolio turnover rate was 436% of the average value of its portfolio.

What are the Portfolio's principal investment strategies?

The Portfolio allocates its investments principally among the following three sectors of the fixed income securities markets: the U.S. investment grade sector, the U.S. high yield sector, and the international sector. Under normal circumstances, the Portfolio will invest at least 80% of its net assets, plus any borrowings for investment purposes, in fixed income securities (80% Policy). The Portfolio's 80% Policy may be changed without shareholder approval. However, shareholders will be given notice at least 60 days prior to any such change.

The Manager will determine how much of the Portfolio to allocate to each of the three sectors, based on its evaluation of economic and market conditions and its assessment of the returns and potential for appreciation that can be achieved from investments in each of the three sectors. The Manager will periodically reallocate the Portfolio's assets, as deemed necessary. The relative proportion of the Portfolio's assets to be allocated among sectors is described below.

U.S. investment grade sector Under normal circumstances, between 50% and 100% of the Portfolio's total assets will be invested in the U.S. investment grade sector. In managing the Portfolio's assets allocated to the U.S. investment grade sector, the Manager will invest principally in debt obligations issued or guaranteed by the U.S. government, its agencies, or instrumentalities, and by U.S. corporations. The corporate debt obligations in which the Portfolio may invest include bonds, notes, debentures, and commercial paper of U.S. companies. The U.S. government securities in which the


Portfolio may invest include a variety of securities that are issued or guaranteed as to the payment of principal and interest by the U.S. government, and by various agencies or instrumentalities that have been established or sponsored by the U.S. government.
 

The U.S. investment grade sector of the Portfolio's assets may also be invested in mortgage-backed securities (MBS) issued or guaranteed by the U.S. government, its agencies, or instrumentalities or by government-sponsored corporations. Other MBS in which the Portfolio may invest are issued by certain private, nongovernment entities. Subject to the quality limitations, the Portfolio may also invest in securities that are backed by assets such as receivables on home equity and credit card loans, automobile, mobile home, recreational vehicle, and other loans, wholesale dealer floor plans, and leases.
 

Securities purchased by the Portfolio within this sector will be rated in one of the four highest rating categories or will be unrated securities that the Manager determines are of comparable quality.
 

U.S. high yield sector Under normal circumstances, up to 30% of the Portfolio's total assets will be allocated to the high yield sector. The Manager will invest the Portfolio's assets that are allocated to the high yield sector primarily in those securities having a liberal and consistent yield and those tending to reduce the risk of market fluctuations. The Portfolio may invest in corporate debt obligations, including, notes, which may be convertible or nonconvertible, commercial paper, units consisting of bonds with stock or warrants to buy stock attached, debentures, convertible debentures, zero-coupon bonds, and PIK securities.
 

The Portfolio will invest in both rated and unrated bonds. The rated bonds that the Portfolio may purchase in this sector will generally be rated lower than BBB- by S&P, Baa3 by Moody's, or similarly rated by another NRSRO.
 

International sector The Portfolio may invest up to 30% of its total assets in the international sector. The international sector invests primarily in fixed income securities of issuers organized or having a majority of their assets or deriving a majority of their operating income in foreign countries. These fixed income securities include foreign government securities, debt obligations of foreign companies, and securities issued by supranational entities. A supranational entity is an entity established or financially supported by the national governments of one or more countries to promote reconstruction or development. Examples of supranational entities include, among others, the International Bank for Reconstruction and Development (more commonly known as the World Bank), the European Economic Community, the European Investment Bank, the Inter-American Development Bank, and the Asian Development Bank.
 

The Portfolio may invest in securities issued in any currency and may hold foreign currencies. Securities of issuers within a given country may be denominated in the currency of another country or in multinational currency units, such as the euro. The Portfolio may, from time to time, purchase or sell foreign currencies and/or engage in forward foreign currency transactions in order to expedite settlement of Portfolio transactions and to minimize currency value fluctuations. Currency considerations carry a special risk for the Portfolio to the extent that it allocates a significant portion of its assets to foreign securities.
 

The Portfolio will invest in both rated and unrated foreign securities. It may purchase securities of issuers in any foreign country, developed and underdeveloped. These investments may include direct obligations of issuers located in emerging markets countries.

The Portfolio's total non-U.S. dollar currency exposure will be limited, in aggregate, to no more than 10% of net assets, and the Portfolio's investments in emerging markets securities will be limited to no more than 15% of the Portfolio's net assets.

The Portfolio may hold a substantial portion of its assets in cash or short-term fixed income obligations in unusual market conditions to meet redemption requests, for temporary defensive purposes, and pending investment. The Portfolio may also use a wide range of derivatives instruments, typically including options, futures contracts, options on futures contracts, and swaps. The Portfolio will use derivatives for both hedging and nonhedging purposes. For example, the Portfolio may invest in: futures and options to manage duration and for defensive purposes, such as to protect gains or hedge against potential losses in the portfolio without actually selling a security, or to stay fully invested; forward foreign currency contracts to manage foreign currency exposure; interest rate swaps to neutralize the impact of interest rate changes; credit default swaps to hedge against bond defaults, to manage credit exposure or to enhance total return; and index swaps to enhance return or to effect diversification. The Portfolio will not use derivatives for reasons inconsistent with its investment objective.

What are the principal risks of investing in the Portfolio?

Investing in any mutual fund involves the risk that you may lose part or all of the money you invest. Over time, the value of your investment in the Portfolio will increase and decrease according to changes in the value of the securities in its portfolio. Principal risks include:

Risk Definition
Market risk The risk that all or a majority of the securities in a certain market — such as the stock or bond market — will decline in value because of factors such as adverse political or economic conditions, future expectations, investor confidence, or heavy institutional selling.
Credit risk The risk that an issuer of a debt security, including a governmental issuer, or an entity that insures a bond may be unable to make interest payments and repay principal in a timely manner.
Interest rate risk The risk that securities will decrease in value if interest rates rise. The risk is generally associated with bonds; however, because companies in the real estate sector and smaller companies often borrow money to finance their operations, they may be adversely affected by rising interest rates.
Bank loans and other direct
indebtedness risk
The risk that the portfolio will not receive payment of principal, interest, and other amounts due in connection with these investments and will depend primarily on the financial condition of the borrower and the lending institution.
Prepayment risk The risk that the principal on a bond that is held by a portfolio will be prepaid prior to maturity at a time when interest rates are lower than what that bond was paying. A portfolio may then have to reinvest that money at a lower interest rate.
High yield risk The risk that high yield securities, commonly known as “junk bonds,” are subject to reduced creditworthiness of issuers; increased risk of default and a more limited and less liquid secondary market than higher rated securities; and greater price volatility and risk of loss of income and principal than are higher rated securities because they are rated below investment grade. High yield bonds are sometimes issued by municipalities with less financial strength and therefore less ability to make projected debt payments on the bonds.
Foreign risk The risk that foreign securities (particularly in emerging markets) may be adversely affected by political instability; changes in currency exchange rates; inefficient markets and higher transaction costs; foreign economic conditions; the imposition of economic or trade sanctions; or inadequate or different regulatory and accounting standards.
Currency risk The risk that the value of a portfolio's investments may be negatively affected by changes in foreign currency exchange rates.
Forward foreign currency risk The use of forward foreign currency exchange contracts may substantially change a fund's exposure to currency exchange rates and could result in losses to the fund if currencies do not perform as the Manager expects. The use of these investments as a hedging technique to reduce a fund's exposure to currency risks may also reduce its ability to benefit from favorable changes in currency exchange rates.
Foreign government/
supranational securities risk
The risk that a foreign government or government-related issuer may be unable to make timely payments on its external debt obligations.
Derivatives risk Derivatives contracts, such as options, futures, and swaps, may involve additional expenses (such as the payment of premiums) and are subject to significant loss if a security or a securities index to which a derivatives contract is associated moves in the opposite direction from what the portfolio manager anticipated. Derivatives contracts are also subject to the risk that the counterparty may fail to perform its obligations under the contract due to financial difficulties (such as a bankruptcy or reorganization).
Liquidity risk The possibility that securities cannot be readily sold within seven days at approximately the price at which a portfolio has valued them.
Investments not guaranteed by
Delaware Management Company
(Manager) or its affiliates
Neither the Manager nor its affiliates noted in this document are authorized deposit-taking institutions for the purposes of the Banking Act 1959 (Commonwealth of Australia). The obligations of these entities do not represent deposits or other liabilities of Macquarie Bank Limited (MBL). MBL does not guarantee or otherwise provide assurance in respect of the obligations of these entities, unless noted otherwise.


How has The Core Plus Fixed Income Portfolio performed?
The bar chart and table below provide some indication of the risks of investing in the Portfolio by showing changes in the Portfolio's performance from year to year and by showing how the Portfolio's average annual total returns for the 1-, 5-, and 10-year periods compare with those of a broad measure of market performance. The Portfolio's past performance (before and after taxes) is not necessarily an indication of how it will perform in the future. The returns reflect any expense caps in effect during these periods. The returns would be lower without the expense caps. You may obtain the Portfolio's most recently available month-end performance by calling 800 231-8002 or by visiting our website at delawareinvestments.com/institutional.
Year-by-year total return (The Core Plus Fixed Income Portfolio)
Bar Chart
During the periods illustrated in this bar chart, The Core Plus Fixed Income Portfolio's highest quarterly return was 9.22% for the quarter ended Sept. 30, 2009 and its lowest quarterly return was -2.84% for the quarter ended June 30, 2013.
Average annual total returns for periods ended December 31, 2015
Average Annual Total Returns Equity Oriented or Fixed Income Oriented Funds The Core Plus Fixed Income Portfolio
1 Year
5 Years
10 Years
DPT CLASS
(0.17%) 3.72% 5.58%
DPT CLASS After Taxes on Distributions
(1.16%) 2.66% 3.89%
DPT CLASS After Taxes on Distributions and sale of Portfolio shares
(0.10%) 2.44% 3.68%
Barclays U.S. Aggregate Index
0.55% 3.25% 4.51%

Actual after-tax returns depend on the investor's individual tax situation and may differ from the returns shown. After-tax returns are not relevant for shares held in tax-deferred investment vehicles such as employer-sponsored 401(k) plans and individual retirement accounts (IRAs). The after-tax returns shown are calculated using the highest individual federal marginal income tax rates in effect during the Portfolio's lifetime and do not reflect the impact of state and local taxes.

v2.4.1.9
Label Element Value
Risk/Return: rr_RiskReturnAbstract  
Risk/Return, Heading rr_RiskReturnHeading

The Core Plus Fixed Income Portfolio

Investment Objective, Heading rr_ObjectiveHeading

What is the Portfolio's investment objective?

Investment Objective, Primary rr_ObjectivePrimaryTextBlock

The Core Plus Fixed Income Portfolio seeks maximum long-term total return, consistent with reasonable risk.

Expense, Heading rr_ExpenseHeading

What are the Portfolio's fees and expenses?

Expense, Narrative rr_ExpenseNarrativeTextBlock

The table below describes the fees and expenses that you may pay if you buy and hold shares of the Portfolio.

Operating Expenses, Caption rr_OperatingExpensesCaption

Annual portfolio operating expenses (expenses that you pay each year as a percentage of the value of your investment)

Fee Waiver or Reimbursement over Assets, Date of Termination rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination
Feb. 28, 2017
Portfolio Turnover, Heading rr_PortfolioTurnoverHeading

Portfolio turnover

Portfolio Turnover rr_PortfolioTurnoverTextBlock

The Portfolio pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Portfolio shares are held in a taxable account. These costs, which are not reflected in annual portfolio operating expenses or in the example, affect the Portfolio's performance. During the most recent fiscal year, the Portfolio's portfolio turnover rate was 436% of the average value of its portfolio.

Portfolio Turnover, Rate rr_PortfolioTurnoverRate 436.00%rr_PortfolioTurnoverRate
Expense Example, Heading rr_ExpenseExampleHeading
Example
Expense Example, Narrative rr_ExpenseExampleNarrativeTextBlock
This example is intended to help you compare the cost of investing in the Portfolio with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the Portfolio for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and reflects the Manager's expense waivers and reimbursements for the 1-year contractual period and the total operating expenses without waivers for years 2 through 10. Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Investment Strategy, Heading rr_StrategyHeading

What are the Portfolio's principal investment strategies?

Investment Strategy, Narrative rr_StrategyNarrativeTextBlock

The Portfolio allocates its investments principally among the following three sectors of the fixed income securities markets: the U.S. investment grade sector, the U.S. high yield sector, and the international sector. Under normal circumstances, the Portfolio will invest at least 80% of its net assets, plus any borrowings for investment purposes, in fixed income securities (80% Policy). The Portfolio's 80% Policy may be changed without shareholder approval. However, shareholders will be given notice at least 60 days prior to any such change.

The Manager will determine how much of the Portfolio to allocate to each of the three sectors, based on its evaluation of economic and market conditions and its assessment of the returns and potential for appreciation that can be achieved from investments in each of the three sectors. The Manager will periodically reallocate the Portfolio's assets, as deemed necessary. The relative proportion of the Portfolio's assets to be allocated among sectors is described below.

U.S. investment grade sector Under normal circumstances, between 50% and 100% of the Portfolio's total assets will be invested in the U.S. investment grade sector. In managing the Portfolio's assets allocated to the U.S. investment grade sector, the Manager will invest principally in debt obligations issued or guaranteed by the U.S. government, its agencies, or instrumentalities, and by U.S. corporations. The corporate debt obligations in which the Portfolio may invest include bonds, notes, debentures, and commercial paper of U.S. companies. The U.S. government securities in which the


Portfolio may invest include a variety of securities that are issued or guaranteed as to the payment of principal and interest by the U.S. government, and by various agencies or instrumentalities that have been established or sponsored by the U.S. government.
 

The U.S. investment grade sector of the Portfolio's assets may also be invested in mortgage-backed securities (MBS) issued or guaranteed by the U.S. government, its agencies, or instrumentalities or by government-sponsored corporations. Other MBS in which the Portfolio may invest are issued by certain private, nongovernment entities. Subject to the quality limitations, the Portfolio may also invest in securities that are backed by assets such as receivables on home equity and credit card loans, automobile, mobile home, recreational vehicle, and other loans, wholesale dealer floor plans, and leases.
 

Securities purchased by the Portfolio within this sector will be rated in one of the four highest rating categories or will be unrated securities that the Manager determines are of comparable quality.
 

U.S. high yield sector Under normal circumstances, up to 30% of the Portfolio's total assets will be allocated to the high yield sector. The Manager will invest the Portfolio's assets that are allocated to the high yield sector primarily in those securities having a liberal and consistent yield and those tending to reduce the risk of market fluctuations. The Portfolio may invest in corporate debt obligations, including, notes, which may be convertible or nonconvertible, commercial paper, units consisting of bonds with stock or warrants to buy stock attached, debentures, convertible debentures, zero-coupon bonds, and PIK securities.
 

The Portfolio will invest in both rated and unrated bonds. The rated bonds that the Portfolio may purchase in this sector will generally be rated lower than BBB- by S&P, Baa3 by Moody's, or similarly rated by another NRSRO.
 

International sector The Portfolio may invest up to 30% of its total assets in the international sector. The international sector invests primarily in fixed income securities of issuers organized or having a majority of their assets or deriving a majority of their operating income in foreign countries. These fixed income securities include foreign government securities, debt obligations of foreign companies, and securities issued by supranational entities. A supranational entity is an entity established or financially supported by the national governments of one or more countries to promote reconstruction or development. Examples of supranational entities include, among others, the International Bank for Reconstruction and Development (more commonly known as the World Bank), the European Economic Community, the European Investment Bank, the Inter-American Development Bank, and the Asian Development Bank.
 

The Portfolio may invest in securities issued in any currency and may hold foreign currencies. Securities of issuers within a given country may be denominated in the currency of another country or in multinational currency units, such as the euro. The Portfolio may, from time to time, purchase or sell foreign currencies and/or engage in forward foreign currency transactions in order to expedite settlement of Portfolio transactions and to minimize currency value fluctuations. Currency considerations carry a special risk for the Portfolio to the extent that it allocates a significant portion of its assets to foreign securities.
 

The Portfolio will invest in both rated and unrated foreign securities. It may purchase securities of issuers in any foreign country, developed and underdeveloped. These investments may include direct obligations of issuers located in emerging markets countries.

The Portfolio's total non-U.S. dollar currency exposure will be limited, in aggregate, to no more than 10% of net assets, and the Portfolio's investments in emerging markets securities will be limited to no more than 15% of the Portfolio's net assets.

The Portfolio may hold a substantial portion of its assets in cash or short-term fixed income obligations in unusual market conditions to meet redemption requests, for temporary defensive purposes, and pending investment. The Portfolio may also use a wide range of derivatives instruments, typically including options, futures contracts, options on futures contracts, and swaps. The Portfolio will use derivatives for both hedging and nonhedging purposes. For example, the Portfolio may invest in: futures and options to manage duration and for defensive purposes, such as to protect gains or hedge against potential losses in the portfolio without actually selling a security, or to stay fully invested; forward foreign currency contracts to manage foreign currency exposure; interest rate swaps to neutralize the impact of interest rate changes; credit default swaps to hedge against bond defaults, to manage credit exposure or to enhance total return; and index swaps to enhance return or to effect diversification. The Portfolio will not use derivatives for reasons inconsistent with its investment objective.

Strategy Portfolio Concentration rr_StrategyPortfolioConcentration
Under normal circumstances, the Portfolio will invest at least 80% of its net assets, plus any borrowings for investment purposes, in fixed income securities (80% Policy). The Portfolio's 80% Policy may be changed without shareholder approval. However, shareholders will be given notice at least 60 days prior to any such change.
Risk, Heading rr_RiskHeading

What are the principal risks of investing in the Portfolio?

Risk, Narrative rr_RiskNarrativeTextBlock

Investing in any mutual fund involves the risk that you may lose part or all of the money you invest. Over time, the value of your investment in the Portfolio will increase and decrease according to changes in the value of the securities in its portfolio. Principal risks include:

Risk Definition
Market risk The risk that all or a majority of the securities in a certain market — such as the stock or bond market — will decline in value because of factors such as adverse political or economic conditions, future expectations, investor confidence, or heavy institutional selling.
Credit risk The risk that an issuer of a debt security, including a governmental issuer, or an entity that insures a bond may be unable to make interest payments and repay principal in a timely manner.
Interest rate risk The risk that securities will decrease in value if interest rates rise. The risk is generally associated with bonds; however, because companies in the real estate sector and smaller companies often borrow money to finance their operations, they may be adversely affected by rising interest rates.
Bank loans and other direct
indebtedness risk
The risk that the portfolio will not receive payment of principal, interest, and other amounts due in connection with these investments and will depend primarily on the financial condition of the borrower and the lending institution.
Prepayment risk The risk that the principal on a bond that is held by a portfolio will be prepaid prior to maturity at a time when interest rates are lower than what that bond was paying. A portfolio may then have to reinvest that money at a lower interest rate.
High yield risk The risk that high yield securities, commonly known as “junk bonds,” are subject to reduced creditworthiness of issuers; increased risk of default and a more limited and less liquid secondary market than higher rated securities; and greater price volatility and risk of loss of income and principal than are higher rated securities because they are rated below investment grade. High yield bonds are sometimes issued by municipalities with less financial strength and therefore less ability to make projected debt payments on the bonds.
Foreign risk The risk that foreign securities (particularly in emerging markets) may be adversely affected by political instability; changes in currency exchange rates; inefficient markets and higher transaction costs; foreign economic conditions; the imposition of economic or trade sanctions; or inadequate or different regulatory and accounting standards.
Currency risk The risk that the value of a portfolio's investments may be negatively affected by changes in foreign currency exchange rates.
Forward foreign currency risk The use of forward foreign currency exchange contracts may substantially change a fund's exposure to currency exchange rates and could result in losses to the fund if currencies do not perform as the Manager expects. The use of these investments as a hedging technique to reduce a fund's exposure to currency risks may also reduce its ability to benefit from favorable changes in currency exchange rates.
Foreign government/
supranational securities risk
The risk that a foreign government or government-related issuer may be unable to make timely payments on its external debt obligations.
Derivatives risk Derivatives contracts, such as options, futures, and swaps, may involve additional expenses (such as the payment of premiums) and are subject to significant loss if a security or a securities index to which a derivatives contract is associated moves in the opposite direction from what the portfolio manager anticipated. Derivatives contracts are also subject to the risk that the counterparty may fail to perform its obligations under the contract due to financial difficulties (such as a bankruptcy or reorganization).
Liquidity risk The possibility that securities cannot be readily sold within seven days at approximately the price at which a portfolio has valued them.
Investments not guaranteed by
Delaware Management Company
(Manager) or its affiliates
Neither the Manager nor its affiliates noted in this document are authorized deposit-taking institutions for the purposes of the Banking Act 1959 (Commonwealth of Australia). The obligations of these entities do not represent deposits or other liabilities of Macquarie Bank Limited (MBL). MBL does not guarantee or otherwise provide assurance in respect of the obligations of these entities, unless noted otherwise.


Risk, Lose Money rr_RiskLoseMoney
Investing in any mutual fund involves the risk that you may lose part or all of the money you invest.
Risk, Not Insured Depository Institution rr_RiskNotInsuredDepositoryInstitution
Neither the Manager nor its affiliates noted in this document are authorized deposit-taking institutions for the purposes of the Banking Act 1959 (Commonwealth of Australia). The obligations of these entities do not represent deposits or other liabilities of Macquarie Bank Limited (MBL). MBL does not guarantee or otherwise provide assurance in respect of the obligations of these entities, unless noted otherwise.
Bar Chart and Performance Table, Heading rr_BarChartAndPerformanceTableHeading
How has The Core Plus Fixed Income Portfolio performed?
Performance, Narrative rr_PerformanceNarrativeTextBlock
The bar chart and table below provide some indication of the risks of investing in the Portfolio by showing changes in the Portfolio's performance from year to year and by showing how the Portfolio's average annual total returns for the 1-, 5-, and 10-year periods compare with those of a broad measure of market performance. The Portfolio's past performance (before and after taxes) is not necessarily an indication of how it will perform in the future. The returns reflect any expense caps in effect during these periods. The returns would be lower without the expense caps. You may obtain the Portfolio's most recently available month-end performance by calling 800 231-8002 or by visiting our website at delawareinvestments.com/institutional.
Performance, Information Illustrates Variability of Returns rr_PerformanceInformationIllustratesVariabilityOfReturns

The bar chart and table below provide some indication of the risks of investing in the Portfolio by showing changes in the Portfolio's performance from year to year and by showing how the Portfolio's average annual total returns for the 1-, 5-, and 10-year periods compare with those of a broad measure of market performance.

Performance Availability Phone rr_PerformanceAvailabilityPhone

800 231-8002

Performance Availability Website Address rr_PerformanceAvailabilityWebSiteAddress

delawareinvestments.com/institutional

Performance Past Does Not Indicate Future rr_PerformancePastDoesNotIndicateFuture

The Portfolio's past performance (before and after taxes) is not necessarily an indication of how it will perform in the future.

Bar Chart, Heading rr_BarChartHeading
Year-by-year total return (The Core Plus Fixed Income Portfolio)
Bar Chart, Closing rr_BarChartClosingTextBlock
During the periods illustrated in this bar chart, The Core Plus Fixed Income Portfolio's highest quarterly return was 9.22% for the quarter ended Sept. 30, 2009 and its lowest quarterly return was -2.84% for the quarter ended June 30, 2013.
Highest Quarterly Return, Label rr_HighestQuarterlyReturnLabel

highest quarterly return

Highest Quarterly Return, Date rr_BarChartHighestQuarterlyReturnDate Sep. 30, 2009
Highest Quarterly Return rr_BarChartHighestQuarterlyReturn 9.22%rr_BarChartHighestQuarterlyReturn
Lowest Quarterly Return, Label rr_LowestQuarterlyReturnLabel

lowest quarterly return

Lowest Quarterly Return, Date rr_BarChartLowestQuarterlyReturnDate Jun. 30, 2013
Lowest Quarterly Return rr_BarChartLowestQuarterlyReturn (2.84%)rr_BarChartLowestQuarterlyReturn
Performance Table, Heading rr_PerformanceTableHeading
Average annual total returns for periods ended December 31, 2015
Performance Table Uses Highest Federal Rate rr_PerformanceTableUsesHighestFederalRate
The after-tax returns shown are calculated using the highest individual federal marginal income tax rates in effect during the Portfolio's lifetime and do not reflect the impact of state and local taxes.
Performance Table Not Relevant to Tax Deferred rr_PerformanceTableNotRelevantToTaxDeferred
After-tax returns are not relevant for shares held in tax-deferred investment vehicles such as employer-sponsored 401(k) plans and individual retirement accounts (IRAs).
Performance Table, Closing rr_PerformanceTableClosingTextBlock

Actual after-tax returns depend on the investor's individual tax situation and may differ from the returns shown. After-tax returns are not relevant for shares held in tax-deferred investment vehicles such as employer-sponsored 401(k) plans and individual retirement accounts (IRAs). The after-tax returns shown are calculated using the highest individual federal marginal income tax rates in effect during the Portfolio's lifetime and do not reflect the impact of state and local taxes.

Barclays U.S. Aggregate Index
 
Risk/Return: rr_RiskReturnAbstract  
Index No Deduction for Fees, Expenses, Taxes rr_IndexNoDeductionForFeesExpensesTaxes
reflects no deduction for fees, expenses, or taxes
1 Year rr_AverageAnnualReturnYear01 0.55%rr_AverageAnnualReturnYear01
/ dei_DocumentInformationDocumentAxis
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/ rr_PerformanceMeasureAxis
= dpt_BarclaysUSAggregateIndexMember
5 Years rr_AverageAnnualReturnYear05 3.25%rr_AverageAnnualReturnYear05
/ dei_DocumentInformationDocumentAxis
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/ dei_LegalEntityAxis
= dpt_S000003939Member
/ rr_PerformanceMeasureAxis
= dpt_BarclaysUSAggregateIndexMember
10 Years rr_AverageAnnualReturnYear10 4.51%rr_AverageAnnualReturnYear10
/ dei_DocumentInformationDocumentAxis
= dpt_ProspectusOneMember
/ dei_LegalEntityAxis
= dpt_S000003939Member
/ rr_PerformanceMeasureAxis
= dpt_BarclaysUSAggregateIndexMember
DPT CLASS
 
Risk/Return: rr_RiskReturnAbstract  
Management fees rr_ManagementFeesOverAssets 0.43%rr_ManagementFeesOverAssets
/ dei_DocumentInformationDocumentAxis
= dpt_ProspectusOneMember
/ dei_LegalEntityAxis
= dpt_S000003939Member
/ rr_ProspectusShareClassAxis
= dpt_C000011048Member
Distribution and service (12b-1) fees rr_DistributionAndService12b1FeesOverAssets none
Other expenses rr_OtherExpensesOverAssets 0.17%rr_OtherExpensesOverAssets
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[1]
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[1] The Portfolio's investment manager, Delaware Management Company (Manager), has contractually agreed to waive all or a portion of its investment advisory fees and/or pay/reimburse expenses (excluding any 12b-1 fees, acquired fund fees and expenses, taxes, interest, expenses, short sale and dividend interest expenses, brokerage fees, certain insurance costs, and nonroutine expenses or costs, including, but not limited to, those relating to reorganizations, litigation, conducting shareholder meetings, and liquidations) in order to prevent total annual portfolio operating expenses from exceeding 0.45% of the Portfolio's average daily net assets from Feb. 26, 2016 through Feb. 28, 2017. These waivers and reimbursements may only be terminated by agreement of the Manager and the Portfolio.
v2.4.1.9
Equity Oriented or Fixed Income Oriented Funds | The International Equity Portfolio
The International Equity Portfolio

What is the Portfolio's investment objective?

The International Equity Portfolio seeks maximum long-term total return.

What are the Portfolio's fees and expenses?

The table below describes the fees and expenses that you may pay if you buy and hold shares of the Portfolio.

Annual portfolio operating expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses
Equity Oriented or Fixed Income Oriented Funds
The International Equity Portfolio
DPT CLASS
Management fees 0.75%rr_ManagementFeesOverAssets
Distribution and service (12b-1) fees none
Other expenses 0.12%rr_OtherExpensesOverAssets
Total annual portfolio operating expenses 0.87%rr_ExpensesOverAssets

Example

This example is intended to help you compare the cost of investing in the Portfolio with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the Portfolio for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and assumes that the Portfolio's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example (USD $)
1 Year
3 Years
5 Years
10 Years
Equity Oriented or Fixed Income Oriented Funds The International Equity Portfolio DPT CLASS
89 278 482 1,073

Portfolio turnover

The Portfolio pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Portfolio shares are held in a taxable account. These costs, which are not reflected in annual portfolio operating expenses or in the example, affect the Portfolio's performance. During the most recent fiscal year, the Portfolio's portfolio turnover rate was 28% of the average value of its portfolio.

What are the Portfolio's principal investment strategies?

The Portfolio invests primarily in equity securities of companies that are organized, have a majority of their assets, or derive most of their operating income outside the U.S., and that, in the opinion of the Portfolio's portfolio managers are undervalued at the time of purchase based on their fundamental analysis. Investments will be made mainly in marketable securities of companies located in developed countries.

Under normal circumstances, the Portfolio will invest at least 80% of its net assets, plus any borrowings for investment purposes, in equity securities (80% Policy). The Portfolio's 80% Policy may be changed without shareholder approval. However, shareholders will be given notice at least 60 days prior to any such change. Under normal circumstances, the Portfolio will invest at least 40% of its total assets in securities of non-U.S. issuers. This policy is in addition to the 80% Policy.

Equity securities include, but are not to be limited to, common stocks, securities convertible into common stock, securities having common stock characteristics, such as rights and warrants to purchase common stocks, and preferred securities. To the extent that this Portfolio invests in convertible debt securities, those securities will be purchased on the basis of their equity characteristics, and ratings of those securities, if any, will not be an important factor in their selection. Additionally, the Portfolio may, from time to time, hold its assets in cash (which may be U.S. dollars or foreign currencies, including the euro), or may invest in short-term debt securities or other money market instruments. Except when the portfolio managers believe a temporary defensive approach is appropriate, the Portfolio generally will not hold more than 5% of its assets in cash or such short-term instruments.

The portfolio managers' approach in selecting investments for the Portfolio is oriented to individual stock selection and is value driven. In selecting stocks for the Portfolio, the portfolio managers consider movement in the price of individual securities, and the impact of currency adjustment on a U.S.-domiciled, dollar-based investor. The portfolio managers also conduct research on a global basis in an effort to identify securities that have the potential for long-term total return. The center of the research effort is a value-oriented dividend discount methodology applied to individual securities and market analysis that isolates value across country boundaries. This approach focuses on future anticipated dividends and discounts the value of those dividends back to what they would be worth if they were being paid today. Comparisons of the values of different possible investments are then made. The portfolio managers' approach is long-term in orientation, and it is expected that the annual turnover rate of the Portfolio will not exceed 75% under normal circumstances.

In an international portfolio, currency returns can be an integral component of an investment's total return. The portfolio managers will use a purchasing power parity approach to assess the value of individual currencies. Purchasing power parity attempts to identify the amount of goods and services that a dollar will buy in the U.S. and compares that to the amount of a foreign currency required to buy the same amount of goods and services in another country. Eventually, currencies should trade at levels that would make it possible for the dollar to buy the same amount of goods and services overseas as in the United States. When the dollar buys less, the foreign currency may be overvalued. When the dollar buys more, the foreign currency may be undervalued. Securities available in an undervalued currency may offer greater return potential and may be an attractive investment.

Currency considerations carry a special risk for a portfolio of international securities, and the portfolio managers use a purchasing power parity approach to evaluate currency risk. In this regard, the Portfolio may actively carry on hedging activities, and may invest in forward foreign currency exchange contracts to hedge currency risks associated with the purchase of individual securities denominated in a particular currency.

From time to time, the Portfolio may invest up to 30% of its net assets in securities of issuers in the commercial banking industry; to the extent the Portfolio invests 30% of its net assets in such securities, it may be slightly more sensitive to movement in the commercial banking industry.

The Portfolio may make limited use (not more than 15% of its assets) of foreign fixed income securities when, in the portfolio managers' opinion, attractive opportunities exist relative to those available through equity securities or the short-term investments described above. The foreign fixed income securities in which the Portfolio may invest may be U.S. dollar or foreign currency denominated, including the euro, and may include obligations of foreign governments, foreign government agencies, supranational organizations or corporations, and other private entities. Such governmental fixed income securities will be, at the time of purchase, of the highest quality (for example, AAA by S&P or Aaa by Moody's) or of comparable quality. Corporate fixed income securities will be, at the time of purchase, rated in one of the top two rating categories (for example, AAA and AA by S&P or Aaa and Aa by Moody's) or of comparable quality.

What are the principal risks of investing in the Portfolio?

Investing in any mutual fund involves the risk that you may lose part or all of the money you invest. Over time, the value of your investment in the Portfolio will increase and decrease according to changes in the value of the securities in its portfolio. Principal risks include:

Market risk — The risk that all or a majority of the securities in a certain market — such as the stock or bond market — will decline in value because of factors such as adverse political or economic conditions, future expectations, investor confidence, or heavy institutional selling.

Foreign risk — The risk that foreign securities (particularly in emerging markets) may be adversely affected by political instability; changes in currency exchange rates; inefficient markets and higher transaction costs; foreign economic conditions; the imposition of economic or trade sanctions; or inadequate or different regulatory and accounting standards.

Foreign government/supranational securities risk — The risk that a foreign government or government-related issuer may be unable to make timely payments on its external debt obligations.

Currency risk — The risk that the value of a portfolio's investments may be negatively affected by changes in foreign currency exchange rates.

Derivatives risk — Derivatives contracts, such as options, futures, and swaps, may involve additional expenses (such as the payment of premiums) and are subject to significant loss if a security or a securities index to which a derivatives contract is associated moves in the opposite direction from what the portfolio manager anticipated. Derivatives contracts are also subject to the risk that the counterparty may fail to perform its obligations under the contract due to financial difficulties (such as a bankruptcy or reorganization).

Interest rate risk — The risk that securities will decrease in value if interest rates rise. The risk is generally associated with bonds; however, because companies in the real estate sector and smaller companies often borrow money to finance their operations, they may be adversely affected by rising interest rates.

Liquidity risk — The possibility that securities cannot be readily sold within seven days at approximately the price at which a portfolio has valued them.

Investments not guaranteed by Delaware Management Company (Manager) or its affiliatesNeither the Manager nor its affiliates noted in this document are authorized deposit-taking institutions for the purposes of the Banking Act 1959 (Commonwealth of Australia). The obligations of these entities do not represent deposits or other liabilities of Macquarie Bank Limited (MBL). MBL does not guarantee or otherwise provide assurance in respect of the obligations of these entities, unless noted otherwise.

How has The International Equity Portfolio performed?

The bar chart and table below provide some indication of the risks of investing in the Portfolio by showing changes in the Portfolio's performance from year to year and by showing how the Portfolio's average annual total returns for the 1-, 5-, and 10-year periods compare with those of a broad measure of market performance. The Portfolio's past performance (before and after taxes) is not necessarily an indication of how it will perform in the future. The returns reflect any expense caps in effect during these periods. The returns would be lower without the expense caps. You may obtain the Portfolio's most recently available month-end performance by calling 800 231-8002 or by visiting our website at delawareinvestments.com/institutional.

Year-by-year total return

Bar Chart

During the periods illustrated in this bar chart, The International Equity Portfolio's highest quarterly return was 20.51% for the quarter ended June 30, 2009 and its lowest quarterly return was -17.17% for the quarter ended March 31, 2009.

Average annual total returns for periods ended Dec. 31, 2015

Average Annual Total Returns Equity Oriented or Fixed Income Oriented Funds The International Equity Portfolio
1 Year
5 Years
10 Years
DPT CLASS
(3.93%) 3.75% 3.20%
DPT CLASS After Taxes on Distributions
(4.39%) 2.98% 1.96%
DPT CLASS After Taxes on Distributions and sale of Portfolio shares
(1.56%) 3.01% 2.82%
MSCI EAFE Index (gross returns)
(0.39%) 4.07% 3.50%
MSCI EAFE Index (net returns)
(0.81%) 3.60% 3.03%

Actual after-tax returns depend on the investor's individual tax situation and may differ from the returns shown. After-tax returns are not relevant for shares held in tax-deferred investment vehicles such as employer-sponsored 401(k) plans and individual retirement accounts (IRAs). The after-tax returns shown are calculated using the highest individual federal marginal income tax rates in effect during the Portfolio's lifetime and do not reflect the impact of state and local taxes.

v2.4.1.9
Label Element Value
Risk/Return: rr_RiskReturnAbstract  
Risk/Return, Heading rr_RiskReturnHeading
The International Equity Portfolio
Investment Objective, Heading rr_ObjectiveHeading

What is the Portfolio's investment objective?

Investment Objective, Primary rr_ObjectivePrimaryTextBlock

The International Equity Portfolio seeks maximum long-term total return.

Expense, Heading rr_ExpenseHeading

What are the Portfolio's fees and expenses?

Expense, Narrative rr_ExpenseNarrativeTextBlock

The table below describes the fees and expenses that you may pay if you buy and hold shares of the Portfolio.

Operating Expenses, Caption rr_OperatingExpensesCaption

Annual portfolio operating expenses (expenses that you pay each year as a percentage of the value of your investment)

Portfolio Turnover, Heading rr_PortfolioTurnoverHeading

Portfolio turnover

Portfolio Turnover rr_PortfolioTurnoverTextBlock
The Portfolio pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Portfolio shares are held in a taxable account. These costs, which are not reflected in annual portfolio operating expenses or in the example, affect the Portfolio's performance. During the most recent fiscal year, the Portfolio's portfolio turnover rate was 28% of the average value of its portfolio.
Portfolio Turnover, Rate rr_PortfolioTurnoverRate 28.00%rr_PortfolioTurnoverRate
Expense Example, Heading rr_ExpenseExampleHeading

Example

Expense Example, Narrative rr_ExpenseExampleNarrativeTextBlock

This example is intended to help you compare the cost of investing in the Portfolio with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the Portfolio for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and assumes that the Portfolio's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Investment Strategy, Heading rr_StrategyHeading

What are the Portfolio's principal investment strategies?

Investment Strategy, Narrative rr_StrategyNarrativeTextBlock

The Portfolio invests primarily in equity securities of companies that are organized, have a majority of their assets, or derive most of their operating income outside the U.S., and that, in the opinion of the Portfolio's portfolio managers are undervalued at the time of purchase based on their fundamental analysis. Investments will be made mainly in marketable securities of companies located in developed countries.

Under normal circumstances, the Portfolio will invest at least 80% of its net assets, plus any borrowings for investment purposes, in equity securities (80% Policy). The Portfolio's 80% Policy may be changed without shareholder approval. However, shareholders will be given notice at least 60 days prior to any such change. Under normal circumstances, the Portfolio will invest at least 40% of its total assets in securities of non-U.S. issuers. This policy is in addition to the 80% Policy.

Equity securities include, but are not to be limited to, common stocks, securities convertible into common stock, securities having common stock characteristics, such as rights and warrants to purchase common stocks, and preferred securities. To the extent that this Portfolio invests in convertible debt securities, those securities will be purchased on the basis of their equity characteristics, and ratings of those securities, if any, will not be an important factor in their selection. Additionally, the Portfolio may, from time to time, hold its assets in cash (which may be U.S. dollars or foreign currencies, including the euro), or may invest in short-term debt securities or other money market instruments. Except when the portfolio managers believe a temporary defensive approach is appropriate, the Portfolio generally will not hold more than 5% of its assets in cash or such short-term instruments.

The portfolio managers' approach in selecting investments for the Portfolio is oriented to individual stock selection and is value driven. In selecting stocks for the Portfolio, the portfolio managers consider movement in the price of individual securities, and the impact of currency adjustment on a U.S.-domiciled, dollar-based investor. The portfolio managers also conduct research on a global basis in an effort to identify securities that have the potential for long-term total return. The center of the research effort is a value-oriented dividend discount methodology applied to individual securities and market analysis that isolates value across country boundaries. This approach focuses on future anticipated dividends and discounts the value of those dividends back to what they would be worth if they were being paid today. Comparisons of the values of different possible investments are then made. The portfolio managers' approach is long-term in orientation, and it is expected that the annual turnover rate of the Portfolio will not exceed 75% under normal circumstances.

In an international portfolio, currency returns can be an integral component of an investment's total return. The portfolio managers will use a purchasing power parity approach to assess the value of individual currencies. Purchasing power parity attempts to identify the amount of goods and services that a dollar will buy in the U.S. and compares that to the amount of a foreign currency required to buy the same amount of goods and services in another country. Eventually, currencies should trade at levels that would make it possible for the dollar to buy the same amount of goods and services overseas as in the United States. When the dollar buys less, the foreign currency may be overvalued. When the dollar buys more, the foreign currency may be undervalued. Securities available in an undervalued currency may offer greater return potential and may be an attractive investment.

Currency considerations carry a special risk for a portfolio of international securities, and the portfolio managers use a purchasing power parity approach to evaluate currency risk. In this regard, the Portfolio may actively carry on hedging activities, and may invest in forward foreign currency exchange contracts to hedge currency risks associated with the purchase of individual securities denominated in a particular currency.

From time to time, the Portfolio may invest up to 30% of its net assets in securities of issuers in the commercial banking industry; to the extent the Portfolio invests 30% of its net assets in such securities, it may be slightly more sensitive to movement in the commercial banking industry.

The Portfolio may make limited use (not more than 15% of its assets) of foreign fixed income securities when, in the portfolio managers' opinion, attractive opportunities exist relative to those available through equity securities or the short-term investments described above. The foreign fixed income securities in which the Portfolio may invest may be U.S. dollar or foreign currency denominated, including the euro, and may include obligations of foreign governments, foreign government agencies, supranational organizations or corporations, and other private entities. Such governmental fixed income securities will be, at the time of purchase, of the highest quality (for example, AAA by S&P or Aaa by Moody's) or of comparable quality. Corporate fixed income securities will be, at the time of purchase, rated in one of the top two rating categories (for example, AAA and AA by S&P or Aaa and Aa by Moody's) or of comparable quality.

Strategy Portfolio Concentration rr_StrategyPortfolioConcentration
Under normal circumstances, the Portfolio will invest at least 80% of its net assets, plus any borrowings for investment purposes, in equity securities (80% Policy). The Portfolio's 80% Policy may be changed without shareholder approval. However, shareholders will be given notice at least 60 days prior to any such change. Under normal circumstances, the Portfolio will invest at least 40% of its total assets in securities of non-U.S. issuers. This policy is in addition to the 80% Policy.
Risk, Heading rr_RiskHeading

What are the principal risks of investing in the Portfolio?

Risk, Narrative rr_RiskNarrativeTextBlock

Investing in any mutual fund involves the risk that you may lose part or all of the money you invest. Over time, the value of your investment in the Portfolio will increase and decrease according to changes in the value of the securities in its portfolio. Principal risks include:

Market risk — The risk that all or a majority of the securities in a certain market — such as the stock or bond market — will decline in value because of factors such as adverse political or economic conditions, future expectations, investor confidence, or heavy institutional selling.

Foreign risk — The risk that foreign securities (particularly in emerging markets) may be adversely affected by political instability; changes in currency exchange rates; inefficient markets and higher transaction costs; foreign economic conditions; the imposition of economic or trade sanctions; or inadequate or different regulatory and accounting standards.

Foreign government/supranational securities risk — The risk that a foreign government or government-related issuer may be unable to make timely payments on its external debt obligations.

Currency risk — The risk that the value of a portfolio's investments may be negatively affected by changes in foreign currency exchange rates.

Derivatives risk — Derivatives contracts, such as options, futures, and swaps, may involve additional expenses (such as the payment of premiums) and are subject to significant loss if a security or a securities index to which a derivatives contract is associated moves in the opposite direction from what the portfolio manager anticipated. Derivatives contracts are also subject to the risk that the counterparty may fail to perform its obligations under the contract due to financial difficulties (such as a bankruptcy or reorganization).

Interest rate risk — The risk that securities will decrease in value if interest rates rise. The risk is generally associated with bonds; however, because companies in the real estate sector and smaller companies often borrow money to finance their operations, they may be adversely affected by rising interest rates.

Liquidity risk — The possibility that securities cannot be readily sold within seven days at approximately the price at which a portfolio has valued them.

Investments not guaranteed by Delaware Management Company (Manager) or its affiliatesNeither the Manager nor its affiliates noted in this document are authorized deposit-taking institutions for the purposes of the Banking Act 1959 (Commonwealth of Australia). The obligations of these entities do not represent deposits or other liabilities of Macquarie Bank Limited (MBL). MBL does not guarantee or otherwise provide assurance in respect of the obligations of these entities, unless noted otherwise.

Risk, Lose Money rr_RiskLoseMoney
Investing in any mutual fund involves the risk that you may lose part or all of the money you invest.
Risk, Not Insured Depository Institution rr_RiskNotInsuredDepositoryInstitution
Neither the Manager nor its affiliates noted in this document are authorized deposit-taking institutions for the purposes of the Banking Act 1959 (Commonwealth of Australia). The obligations of these entities do not represent deposits or other liabilities of Macquarie Bank Limited (MBL). MBL does not guarantee or otherwise provide assurance in respect of the obligations of these entities, unless noted otherwise.
Bar Chart and Performance Table, Heading rr_BarChartAndPerformanceTableHeading

How has The International Equity Portfolio performed?

Performance, Narrative rr_PerformanceNarrativeTextBlock

The bar chart and table below provide some indication of the risks of investing in the Portfolio by showing changes in the Portfolio's performance from year to year and by showing how the Portfolio's average annual total returns for the 1-, 5-, and 10-year periods compare with those of a broad measure of market performance. The Portfolio's past performance (before and after taxes) is not necessarily an indication of how it will perform in the future. The returns reflect any expense caps in effect during these periods. The returns would be lower without the expense caps. You may obtain the Portfolio's most recently available month-end performance by calling 800 231-8002 or by visiting our website at delawareinvestments.com/institutional.

Performance, Information Illustrates Variability of Returns rr_PerformanceInformationIllustratesVariabilityOfReturns
The bar chart and table below provide some indication of the risks of investing in the Portfolio by showing changes in the Portfolio's performance from year to year and by showing how the Portfolio's average annual total returns for the 1-, 5-, and 10-year periods compare with those of a broad measure of market performance.
Performance Availability Phone rr_PerformanceAvailabilityPhone
800 231-8002
Performance Availability Website Address rr_PerformanceAvailabilityWebSiteAddress
delawareinvestments.com/institutional
Performance Past Does Not Indicate Future rr_PerformancePastDoesNotIndicateFuture
The Portfolio's past performance (before and after taxes) is not necessarily an indication of how it will perform in the future.
Bar Chart, Heading rr_BarChartHeading

Year-by-year total return

Bar Chart, Closing rr_BarChartClosingTextBlock

During the periods illustrated in this bar chart, The International Equity Portfolio's highest quarterly return was 20.51% for the quarter ended June 30, 2009 and its lowest quarterly return was -17.17% for the quarter ended March 31, 2009.

Highest Quarterly Return, Label rr_HighestQuarterlyReturnLabel
highest quarterly return
Highest Quarterly Return, Date rr_BarChartHighestQuarterlyReturnDate Jun. 30, 2009
Highest Quarterly Return rr_BarChartHighestQuarterlyReturn 20.51%rr_BarChartHighestQuarterlyReturn
Lowest Quarterly Return, Label rr_LowestQuarterlyReturnLabel
lowest quarterly return
Lowest Quarterly Return, Date rr_BarChartLowestQuarterlyReturnDate Mar. 31, 2009
Lowest Quarterly Return rr_BarChartLowestQuarterlyReturn (17.17%)rr_BarChartLowestQuarterlyReturn
Performance Table, Heading rr_PerformanceTableHeading

Average annual total returns for periods ended Dec. 31, 2015

Performance Table Uses Highest Federal Rate rr_PerformanceTableUsesHighestFederalRate
The after-tax returns shown are calculated using the highest individual federal marginal income tax rates in effect during the Portfolio's lifetime and do not reflect the impact of state and local taxes.
Performance Table Not Relevant to Tax Deferred rr_PerformanceTableNotRelevantToTaxDeferred
After-tax returns are not relevant for shares held in tax-deferred investment vehicles such as employer-sponsored 401(k) plans and individual retirement accounts (IRAs).
Performance Table, Closing rr_PerformanceTableClosingTextBlock

Actual after-tax returns depend on the investor's individual tax situation and may differ from the returns shown. After-tax returns are not relevant for shares held in tax-deferred investment vehicles such as employer-sponsored 401(k) plans and individual retirement accounts (IRAs). The after-tax returns shown are calculated using the highest individual federal marginal income tax rates in effect during the Portfolio's lifetime and do not reflect the impact of state and local taxes.

MSCI EAFE Index (gross returns)
 
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v2.4.1.9
Alternative / Specialty Mutual Fund | Delaware REIT Fund

Delaware REIT Fund

What are the Fund's investment objectives?

Delaware REIT Fund seeks maximum long-term total return, with capital appreciation as a secondary objective.

What are the Fund's fees and expenses?

The table below describes the fees and expenses that you may pay if you buy and hold shares of the Fund. You may qualify for sales-charge discounts if you and your family invest, or agree to invest in the future, at least $50,000 in Delaware Investments® Funds. More information about these and other discounts is available from your financial intermediary, in the Fund's prospectus under the section entitled "About your account," and in the Fund's statement of additional information (SAI) under the section entitled "Purchasing Shares."

Shareholder fees (fees paid directly from your investment)

Shareholder Fees Alternative / Specialty Mutual Fund Delaware REIT Fund
CLASS A
CLASS C
CLASS R
INSTITUTIONAL CLASS
Maximum sales charge (load) imposed on purchases as apercentage of offering price 5.75%rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none none none
Maximum contingent deferred sales charge (load) as a percentage of original purchase price or redemption price, whichever is lower none 1.00%rr_MaximumDeferredSalesChargeOverOfferingPrice [1] none none
[1] Class C shares redeemed within one year of purchase are subject to a 1.00% contingent deferred sales charge (CDSC).

Annual fund operating expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses Alternative / Specialty Mutual Fund Delaware REIT Fund
CLASS A
CLASS C
CLASS R
INSTITUTIONAL CLASS
Management fees 0.75%rr_ManagementFeesOverAssets 0.75%rr_ManagementFeesOverAssets 0.75%rr_ManagementFeesOverAssets 0.75%rr_ManagementFeesOverAssets
Distribution and service (12b-1) fees 0.25%rr_DistributionAndService12b1FeesOverAssets 1.00%rr_DistributionAndService12b1FeesOverAssets 0.50%rr_DistributionAndService12b1FeesOverAssets none
Other expenses 0.32%rr_OtherExpensesOverAssets 0.32%rr_OtherExpensesOverAssets 0.32%rr_OtherExpensesOverAssets 0.32%rr_OtherExpensesOverAssets
Total annual portfolio operating expenses 1.32%rr_ExpensesOverAssets 2.07%rr_ExpensesOverAssets 1.57%rr_ExpensesOverAssets 1.07%rr_ExpensesOverAssets

Example

This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same.  Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example Alternative / Specialty Mutual Fund Delaware REIT Fund (USD $)
1 Year
3 Years
5 Years
10 Years
CLASS A
702 969 1,257 2,074
CLASS C
310 649 1,114 2,400
CLASS R
160 496 855 1,867
INSTITUTIONAL CLASS
109 340 590 1,306
Expense Example, No Redemption (USD $)
1 Year
3 Years
5 Years
10 Years
Alternative / Specialty Mutual Fund Delaware REIT Fund CLASS C
210 649 1,114 2,400

Portfolio turnover

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 67% of the average value of its portfolio.

What are the Fund's principal investment strategies?

The Fund invests primarily in securities of companies that are principally engaged in the real estate industry. Under normal circumstances, the Fund will invest at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in real estate investment trusts (REITs) (80% policy).

In managing the Fund's portfolio, the Fund's investment manager, Delaware Management Company (Manager), strives to include REITs that represent a variety of different sectors in the real estate industry. As the Manager considers individual REITs for the portfolio, it carefully evaluates each REIT's management team. The Manager generally looks for those that:

  • retain a substantial portion of the properties' cash flow;

  • effectively use capital to expand;

  • have a strong ability to raise rents; and

  • can create a franchise value for the REIT.

The Fund's 80% policy is nonfundamental and may be changed without shareholder approval. Fund shareholders would be given at least 60 days' notice prior to any such change.

What are the principal risks of investing in the Fund?

Investing in any mutual fund involves the risk that you may lose part or all of the money you invest. Over time, the value of your investment in the Fund will increase and decrease according to changes in the value of the securities in the Fund's portfolio. Principal risks include:

Market risk  — The risk that all or a majority of the securities in a certain market — such as the stock or bond market — will decline in value because of factors such as adverse political or economic conditions, future expectations, investor confidence, or heavy institutional selling.

Real estate industry risk  — This risk includes, among others: possible declines in the value of real estate; risks related to general and local economic conditions; possible lack of availability of mortgage funds; overbuilding; extended vacancies of properties; increases in competition, property taxes, and operating expenses; changes in zoning laws; costs resulting from the cleanup of, and liability to third parties resulting from, environmental problems; casualty for condemnation losses; uninsured damages from floods, earthquakes, or other natural disasters; limitations on and variations in rents; and changes in interest rates.

Interest rate risk  — The risk that securities will decrease in value if interest rates rise. The risk is generally associated with bonds; however, because small- and medium-sized companies and companies in the real estate sector often borrow money to finance their operations, they may be adversely affected by rising interest rates.

Foreign risk  — The risk that foreign securities (particularly in emerging markets) may be adversely affected by political instability; changes in currency exchange rates; inefficient markets and higher transaction costs; foreign economic conditions; the imposition of economic or trade sanctions; or inadequate or different regulatory and accounting standards.

Foreign government/supranational risk — The risk that a foreign government or government-related issuer may be unable to make timely payments on its external debt obligations.

Currency risk  — The risk that the value of a portfolio's investments may be negatively affected by changes in foreign currency exchange rates.

Prepayment risk  — The risk that the principal on a bond that is held by a portfolio will be prepaid prior to maturity at a time when interest rates are lower than what that bond was paying. A portfolio may then have to reinvest that money at a lower interest rate.

Liquidity risk  — The possibility that securities cannot be readily sold within seven days at approximately the price at which a portfolio has valued them.

Government and regulatory risk  — The risk that governments or regulatory authorities have, from time to time, taken or considered actions that could adversely affect various sectors of the securities markets and significantly affect fund performance.

Investments not guaranteed by Delaware Management Company (Manager) or its affiliates  — Neither the Manager nor its affiliates noted in this document are authorized deposit-taking institutions for the purposes of the Banking Act 1959 (Commonwealth of Australia). The obligations of these entities do not represent deposits or other liabilities of Macquarie Bank Limited (MBL). MBL does not guarantee or otherwise provide assurance in respect of the obligations of these entities, unless noted otherwise.

How has Delaware REIT Fund performed?

The bar chart and table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year and by showing how the Fund's average annual total returns for the 1-, 5-, and 10-year periods compare with those of a broad measure of market performance. The Fund's past performance (before and after taxes) is not necessarily an indication of how it will perform in the future. The returns reflect any expense caps in effect during these periods. The returns would be lower without the expense caps. You may obtain the Fund's most recently available month-end performance by calling 800 523-1918 or by visiting our website at delawareinvestments.com/performance.

Year-by-year total return (Class A)

Bar Chart

During the periods illustrated in this bar chart, Class A's highest quarterly return was 30.00% for the quarter ended Sept. 30, 2009, and its lowest quarterly return was -36.92% for the quarter ended Dec. 31, 2008. The maximum Class A sales charge of 5.75%, which is normally deducted when you purchase shares, is not reflected in the highest/lowest quarterly returns or in the bar chart. If this fee were included, the returns would be less than those shown. The average annual total returns in the table below do include the sales charge.

Average annual total returns for periods ended December 31, 2015 

Average Annual Total Returns Alternative / Specialty Mutual Fund Delaware REIT Fund
1 Year
5 Years
10 Years
CLASS A
(2.75%) 10.31% 6.33%
CLASS A After Taxes on Distributions
(5.93%) 8.57% 4.12%
CLASS A After Taxes on Distributions and sale of Fund shares
0.15% 7.70% 4.60%
CLASS C
1.49% 10.80% 6.16%
CLASS R
2.87% 11.34% 6.69%
INSTITUTIONAL CLASS
3.47% 11.90% 7.22%
FTSE NAREIT Equity REITs Index
3.20% 11.96% 7.41%

After-tax performance is presented only for Class A shares of the Fund. The after-tax returns for other Fund classes may vary. Actual after-tax returns depend on the investor's individual tax situation and may differ from the returns shown. After-tax returns are not relevant for shares held in tax-deferred investment vehicles such as employer-sponsored 401(k) plans and individual retirement accounts (IRAs). The after-tax returns shown are calculated using the highest individual federal marginal income tax rates in effect during the periods presented and do not reflect the impact of state and local taxes.

v2.4.1.9
Label Element Value
Risk/Return: rr_RiskReturnAbstract  
Risk/Return, Heading rr_RiskReturnHeading

Delaware REIT Fund

Investment Objective, Heading rr_ObjectiveHeading

What are the Fund's investment objectives?

Investment Objective, Primary rr_ObjectivePrimaryTextBlock

Delaware REIT Fund seeks maximum long-term total return, with capital appreciation as a secondary objective.

Expense, Heading rr_ExpenseHeading

What are the Fund's fees and expenses?

Expense, Narrative rr_ExpenseNarrativeTextBlock

The table below describes the fees and expenses that you may pay if you buy and hold shares of the Fund. You may qualify for sales-charge discounts if you and your family invest, or agree to invest in the future, at least $50,000 in Delaware Investments® Funds. More information about these and other discounts is available from your financial intermediary, in the Fund's prospectus under the section entitled "About your account," and in the Fund's statement of additional information (SAI) under the section entitled "Purchasing Shares."

Shareholder Fees, Caption rr_ShareholderFeesCaption

Shareholder fees (fees paid directly from your investment)

Operating Expenses, Caption rr_OperatingExpensesCaption

Annual fund operating expenses (expenses that you pay each year as a percentage of the value of your investment)

Portfolio Turnover, Heading rr_PortfolioTurnoverHeading

Portfolio turnover

Portfolio Turnover rr_PortfolioTurnoverTextBlock

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 67% of the average value of its portfolio.

Portfolio Turnover, Rate rr_PortfolioTurnoverRate 67.00%rr_PortfolioTurnoverRate
Expense Breakpoint, Discounts rr_ExpenseBreakpointDiscounts
You may qualify for sales-charge discounts if you and your family invest, or agree to invest in the future, at least $50,000 in Delaware Investments® Funds. More information about these and other discounts is available from your financial intermediary, in the Fund's prospectus under the section entitled "About your account," and in the Fund's statement of additional information (SAI) under the section entitled "Purchasing Shares."
Expense Breakpoint, Minimum Investment Required Amount rr_ExpenseBreakpointMinimumInvestmentRequiredAmount $ 50,000rr_ExpenseBreakpointMinimumInvestmentRequiredAmount
Expense Example, Heading rr_ExpenseExampleHeading

Example

Expense Example, Narrative rr_ExpenseExampleNarrativeTextBlock

This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same.  Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Investment Strategy, Heading rr_StrategyHeading

What are the Fund's principal investment strategies?

Investment Strategy, Narrative rr_StrategyNarrativeTextBlock

The Fund invests primarily in securities of companies that are principally engaged in the real estate industry. Under normal circumstances, the Fund will invest at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in real estate investment trusts (REITs) (80% policy).

In managing the Fund's portfolio, the Fund's investment manager, Delaware Management Company (Manager), strives to include REITs that represent a variety of different sectors in the real estate industry. As the Manager considers individual REITs for the portfolio, it carefully evaluates each REIT's management team. The Manager generally looks for those that:

  • retain a substantial portion of the properties' cash flow;

  • effectively use capital to expand;

  • have a strong ability to raise rents; and

  • can create a franchise value for the REIT.

The Fund's 80% policy is nonfundamental and may be changed without shareholder approval. Fund shareholders would be given at least 60 days' notice prior to any such change.

Strategy Portfolio Concentration rr_StrategyPortfolioConcentration
Under normal circumstances, the Fund will invest at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in real estate investment trusts (REITs) (80% policy).
Risk, Heading rr_RiskHeading

What are the principal risks of investing in the Fund?

Risk, Narrative rr_RiskNarrativeTextBlock

Investing in any mutual fund involves the risk that you may lose part or all of the money you invest. Over time, the value of your investment in the Fund will increase and decrease according to changes in the value of the securities in the Fund's portfolio. Principal risks include:

Market risk  — The risk that all or a majority of the securities in a certain market — such as the stock or bond market — will decline in value because of factors such as adverse political or economic conditions, future expectations, investor confidence, or heavy institutional selling.

Real estate industry risk  — This risk includes, among others: possible declines in the value of real estate; risks related to general and local economic conditions; possible lack of availability of mortgage funds; overbuilding; extended vacancies of properties; increases in competition, property taxes, and operating expenses; changes in zoning laws; costs resulting from the cleanup of, and liability to third parties resulting from, environmental problems; casualty for condemnation losses; uninsured damages from floods, earthquakes, or other natural disasters; limitations on and variations in rents; and changes in interest rates.

Interest rate risk  — The risk that securities will decrease in value if interest rates rise. The risk is generally associated with bonds; however, because small- and medium-sized companies and companies in the real estate sector often borrow money to finance their operations, they may be adversely affected by rising interest rates.

Foreign risk  — The risk that foreign securities (particularly in emerging markets) may be adversely affected by political instability; changes in currency exchange rates; inefficient markets and higher transaction costs; foreign economic conditions; the imposition of economic or trade sanctions; or inadequate or different regulatory and accounting standards.

Foreign government/supranational risk — The risk that a foreign government or government-related issuer may be unable to make timely payments on its external debt obligations.

Currency risk  — The risk that the value of a portfolio's investments may be negatively affected by changes in foreign currency exchange rates.

Prepayment risk  — The risk that the principal on a bond that is held by a portfolio will be prepaid prior to maturity at a time when interest rates are lower than what that bond was paying. A portfolio may then have to reinvest that money at a lower interest rate.

Liquidity risk  — The possibility that securities cannot be readily sold within seven days at approximately the price at which a portfolio has valued them.

Government and regulatory risk  — The risk that governments or regulatory authorities have, from time to time, taken or considered actions that could adversely affect various sectors of the securities markets and significantly affect fund performance.

Investments not guaranteed by Delaware Management Company (Manager) or its affiliates  — Neither the Manager nor its affiliates noted in this document are authorized deposit-taking institutions for the purposes of the Banking Act 1959 (Commonwealth of Australia). The obligations of these entities do not represent deposits or other liabilities of Macquarie Bank Limited (MBL). MBL does not guarantee or otherwise provide assurance in respect of the obligations of these entities, unless noted otherwise.

Risk, Lose Money rr_RiskLoseMoney
Investing in any mutual fund involves the risk that you may lose part or all of the money you invest.
Risk, Not Insured Depository Institution rr_RiskNotInsuredDepositoryInstitution
Neither the Manager nor its affiliates noted in this document are authorized deposit-taking institutions for the purposes of the Banking Act 1959 (Commonwealth of Australia). The obligations of these entities do not represent deposits or other liabilities of Macquarie Bank Limited (MBL). MBL does not guarantee or otherwise provide assurance in respect of the obligations of these entities, unless noted otherwise.
Bar Chart and Performance Table, Heading rr_BarChartAndPerformanceTableHeading

How has Delaware REIT Fund performed?

Performance, Narrative rr_PerformanceNarrativeTextBlock

The bar chart and table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year and by showing how the Fund's average annual total returns for the 1-, 5-, and 10-year periods compare with those of a broad measure of market performance. The Fund's past performance (before and after taxes) is not necessarily an indication of how it will perform in the future. The returns reflect any expense caps in effect during these periods. The returns would be lower without the expense caps. You may obtain the Fund's most recently available month-end performance by calling 800 523-1918 or by visiting our website at delawareinvestments.com/performance.

Performance, Information Illustrates Variability of Returns rr_PerformanceInformationIllustratesVariabilityOfReturns
The bar chart and table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year and by showing how the Fund's average annual total returns for the 1-, 5-, and 10-year periods compare with those of a broad measure of market performance.
Performance Availability Phone rr_PerformanceAvailabilityPhone
800 523-1918
Performance Availability Website Address rr_PerformanceAvailabilityWebSiteAddress
delawareinvestments.com/performance
Performance Past Does Not Indicate Future rr_PerformancePastDoesNotIndicateFuture
The Fund's past performance (before and after taxes) is not necessarily an indication of how it will perform in the future.
Bar Chart, Heading rr_BarChartHeading

Year-by-year total return (Class A)

Bar Chart, Closing rr_BarChartClosingTextBlock

During the periods illustrated in this bar chart, Class A's highest quarterly return was 30.00% for the quarter ended Sept. 30, 2009, and its lowest quarterly return was -36.92% for the quarter ended Dec. 31, 2008. The maximum Class A sales charge of 5.75%, which is normally deducted when you purchase shares, is not reflected in the highest/lowest quarterly returns or in the bar chart. If this fee were included, the returns would be less than those shown. The average annual total returns in the table below do include the sales charge.

Highest Quarterly Return, Label rr_HighestQuarterlyReturnLabel
highest quarterly return
Highest Quarterly Return, Date rr_BarChartHighestQuarterlyReturnDate Sep. 30, 2009
Highest Quarterly Return rr_BarChartHighestQuarterlyReturn 30.00%rr_BarChartHighestQuarterlyReturn
Lowest Quarterly Return, Label rr_LowestQuarterlyReturnLabel
lowest quarterly return
Lowest Quarterly Return, Date rr_BarChartLowestQuarterlyReturnDate Dec. 31, 2008
Lowest Quarterly Return rr_BarChartLowestQuarterlyReturn (36.92%)rr_BarChartLowestQuarterlyReturn
Performance Table, Heading rr_PerformanceTableHeading

Average annual total returns for periods ended December 31, 2015 

Performance Table, Does Reflect Sales Loads rr_PerformanceTableDoesReflectSalesLoads
The average annual total returns in the table below do include the sales charge.
Performance Table Uses Highest Federal Rate rr_PerformanceTableUsesHighestFederalRate
The after-tax returns shown are calculated using the highest individual federal marginal income tax rates in effect during the periods presented and do not reflect the impact of state and local taxes.
Performance Table Not Relevant to Tax Deferred rr_PerformanceTableNotRelevantToTaxDeferred
After-tax returns are not relevant for shares held in tax-deferred investment vehicles such as employer-sponsored 401(k) plans and individual retirement accounts (IRAs).
Performance Table One Class of after Tax Shown [Text] rr_PerformanceTableOneClassOfAfterTaxShown
After-tax performance is presented only for Class A shares of the Fund.
Performance Table, Closing rr_PerformanceTableClosingTextBlock

After-tax performance is presented only for Class A shares of the Fund. The after-tax returns for other Fund classes may vary. Actual after-tax returns depend on the investor's individual tax situation and may differ from the returns shown. After-tax returns are not relevant for shares held in tax-deferred investment vehicles such as employer-sponsored 401(k) plans and individual retirement accounts (IRAs). The after-tax returns shown are calculated using the highest individual federal marginal income tax rates in effect during the periods presented and do not reflect the impact of state and local taxes.

FTSE NAREIT Equity REITs Index
 
Risk/Return: rr_RiskReturnAbstract  
Index No Deduction for Fees, Expenses, Taxes rr_IndexNoDeductionForFeesExpensesTaxes
reflects no deduction for fees, expenses, or taxes
1 Year rr_AverageAnnualReturnYear01 3.20%rr_AverageAnnualReturnYear01
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5 Years rr_AverageAnnualReturnYear05 11.96%rr_AverageAnnualReturnYear05
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CLASS A
 
Risk/Return: rr_RiskReturnAbstract  
Maximum sales charge (load) imposed on purchases as apercentage of offering price rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice 5.75%rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice
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Maximum contingent deferred sales charge (load) as a percentage of original purchase price or redemption price, whichever is lower rr_MaximumDeferredSalesChargeOverOfferingPrice none
Management fees rr_ManagementFeesOverAssets 0.75%rr_ManagementFeesOverAssets
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Distribution and service (12b-1) fees rr_DistributionAndService12b1FeesOverAssets 0.25%rr_DistributionAndService12b1FeesOverAssets
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Other expenses rr_OtherExpensesOverAssets 0.32%rr_OtherExpensesOverAssets
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Total annual portfolio operating expenses rr_ExpensesOverAssets 1.32%rr_ExpensesOverAssets
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1 Year rr_ExpenseExampleYear01 702rr_ExpenseExampleYear01
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3 Years rr_ExpenseExampleYear03 969rr_ExpenseExampleYear03
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5 Years rr_ExpenseExampleYear05 1,257rr_ExpenseExampleYear05
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Annual Return 2006 rr_AnnualReturn2006 32.38%rr_AnnualReturn2006
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Annual Return 2007 rr_AnnualReturn2007 (14.19%)rr_AnnualReturn2007
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Annual Return 2008 rr_AnnualReturn2008 (35.86%)rr_AnnualReturn2008
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Annual Return 2009 rr_AnnualReturn2009 22.85%rr_AnnualReturn2009
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Annual Return 2010 rr_AnnualReturn2010 26.35%rr_AnnualReturn2010
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Annual Return 2011 rr_AnnualReturn2011 10.09%rr_AnnualReturn2011
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Annual Return 2012 rr_AnnualReturn2012 16.41%rr_AnnualReturn2012
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Annual Return 2013 rr_AnnualReturn2013 1.70%rr_AnnualReturn2013
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Annual Return 2014 rr_AnnualReturn2014 28.87%rr_AnnualReturn2014
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Annual Return 2015 rr_AnnualReturn2015 3.18%rr_AnnualReturn2015
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1 Year rr_AverageAnnualReturnYear01 (2.75%)rr_AverageAnnualReturnYear01
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5 Years rr_AverageAnnualReturnYear05 10.31%rr_AverageAnnualReturnYear05
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10 Years rr_AverageAnnualReturnYear10 6.33%rr_AverageAnnualReturnYear10
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CLASS A | After Taxes on Distributions
 
Risk/Return: rr_RiskReturnAbstract  
1 Year rr_AverageAnnualReturnYear01 (5.93%)rr_AverageAnnualReturnYear01
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5 Years rr_AverageAnnualReturnYear05 8.57%rr_AverageAnnualReturnYear05
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10 Years rr_AverageAnnualReturnYear10 4.12%rr_AverageAnnualReturnYear10
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CLASS A | After Taxes on Distributions and sale of Fund shares
 
Risk/Return: rr_RiskReturnAbstract  
1 Year rr_AverageAnnualReturnYear01 0.15%rr_AverageAnnualReturnYear01
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5 Years rr_AverageAnnualReturnYear05 7.70%rr_AverageAnnualReturnYear05
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10 Years rr_AverageAnnualReturnYear10 4.60%rr_AverageAnnualReturnYear10
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CLASS C
 
Risk/Return: rr_RiskReturnAbstract  
Maximum sales charge (load) imposed on purchases as apercentage of offering price rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum contingent deferred sales charge (load) as a percentage of original purchase price or redemption price, whichever is lower rr_MaximumDeferredSalesChargeOverOfferingPrice 1.00%rr_MaximumDeferredSalesChargeOverOfferingPrice
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[1]
Management fees rr_ManagementFeesOverAssets 0.75%rr_ManagementFeesOverAssets
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Distribution and service (12b-1) fees rr_DistributionAndService12b1FeesOverAssets 1.00%rr_DistributionAndService12b1FeesOverAssets
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Other expenses rr_OtherExpensesOverAssets 0.32%rr_OtherExpensesOverAssets
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Total annual portfolio operating expenses rr_ExpensesOverAssets 2.07%rr_ExpensesOverAssets
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1 Year rr_ExpenseExampleYear01 310rr_ExpenseExampleYear01
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3 Years rr_ExpenseExampleYear03 649rr_ExpenseExampleYear03
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5 Years rr_ExpenseExampleYear05 1,114rr_ExpenseExampleYear05
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10 Years rr_ExpenseExampleYear10 2,400rr_ExpenseExampleYear10
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1 Year rr_ExpenseExampleNoRedemptionYear01 210rr_ExpenseExampleNoRedemptionYear01
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CLASS R
 
Risk/Return: rr_RiskReturnAbstract  
Maximum sales charge (load) imposed on purchases as apercentage of offering price rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum contingent deferred sales charge (load) as a percentage of original purchase price or redemption price, whichever is lower rr_MaximumDeferredSalesChargeOverOfferingPrice none
Management fees rr_ManagementFeesOverAssets 0.75%rr_ManagementFeesOverAssets
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Total annual portfolio operating expenses rr_ExpensesOverAssets 1.57%rr_ExpensesOverAssets
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INSTITUTIONAL CLASS
 
Risk/Return: rr_RiskReturnAbstract  
Maximum sales charge (load) imposed on purchases as apercentage of offering price rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum contingent deferred sales charge (load) as a percentage of original purchase price or redemption price, whichever is lower rr_MaximumDeferredSalesChargeOverOfferingPrice none
Management fees rr_ManagementFeesOverAssets 0.75%rr_ManagementFeesOverAssets
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10 Years rr_ExpenseExampleYear10 $ 1,306rr_ExpenseExampleYear10
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1 Year rr_AverageAnnualReturnYear01 3.47%rr_AverageAnnualReturnYear01
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5 Years rr_AverageAnnualReturnYear05 11.90%rr_AverageAnnualReturnYear05
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10 Years rr_AverageAnnualReturnYear10 7.22%rr_AverageAnnualReturnYear10
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[1] Class C shares redeemed within one year of purchase are subject to a 1.00% contingent deferred sales charge (CDSC).
v2.4.1.9
Label Element Value
Risk/Return: rr_RiskReturnAbstract  
Registrant Name dei_EntityRegistrantName DELAWARE POOLED TRUST
Central Index Key dei_EntityCentralIndexKey 0000875352
Document Creation Date dei_DocumentCreationDate Feb. 25, 2016
Document Effective Date dei_DocumentEffectiveDate Feb. 26, 2016
Prospectus Date rr_ProspectusDate Feb. 26, 2016