Label

Element

Value

(Delaware Dividend Income Fund)

Risk/Return:

rr_RiskReturnAbstract

Objective [Heading]

rr_ObjectiveHeading

What are the Fund's investment objectives?

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

Delaware Dividend Income Fund seeks to provide high current income and an investment that has the potential for capital appreciation.

Expense [Heading]

rr_ExpenseHeading

What are the Fund's fees and expenses?

Expense Narrative [Text Block]

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 advisor, 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 Discounts [Text]

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 advisor, 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

$ 50,000

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

Shareholder fees (fees paid directly from your investment)

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

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

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

Expense Example Narrative [Text Block]

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:

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

Portfolio turnover

Portfolio Turnover [Text Block]

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 the 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 56% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

56.00%

Strategy [Heading]

rr_StrategyHeading

What are the Fund's principal investment strategies?

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

The Fund invests primarily in income-generating securities (debt and equity), which may include equity securities of large, well-established companies, and debt securities, including high yield, high-risk corporate bonds, investment grade fixed income securities, and U.S. government securities.

Under normal circumstances, at least 50% of the Fund's total assets will be invested in income-generating equity securities. In making investments in income-generating equity securities, the Fund may invest an unlimited portion of its total assets in convertible securities without regard to credit quality. While debt securities may comprise up to 50% of the Fund's total assets, no more than 45% of the Fund's total assets will be invested in high yield, high-risk debt securities. No more than 25% of the Fund's total assets will be invested in any one industry sector nor, as to 75% of the Fund's total assets, will more than 5% be invested in securities of any one issuer. The Fund may invest up to 30% of its total assets in foreign equity and debt securities. The Fund will not, however, invest more than 10% of its total assets in securities of issuers principally located or principally operating in markets of emerging countries.

Within the percentage guidelines noted above, the Fund's investment manager, Delaware Management Company (Manager), will determine the proportion of the Fund's assets that will be allocated to income-generating equity securities and equity equivalents and to debt securities, based on its analysis of economic and market conditions and its assessment of the income and potential for appreciation that can be achieved from investments in such asset classes. It is expected that the proportion of the Fund's total assets invested in income-generating equity securities and equity equivalent securities will vary from 50% to 100% of the Fund's total assets. The proportion of the Fund's total assets in debt securities will correspondingly vary from 0% to 50% of the Fund's total assets.

The Fund may use a wide range of derivative instruments, typically including options, futures contracts, options on futures contracts, and credit default swaps. The Fund will use derivatives for both hedging and nonhedging purposes. For example, the Fund 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; and credit default swaps to hedge against bond defaults, to manage credit exposure, or to enhance total return.

Risk [Heading]

rr_RiskHeading

What are the principal risks of investing in the Fund?

Risk Narrative [Text Block]

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:

Investments not guaranteed by Delaware Management Company (Manager) or its affiliates — Investments in the Fund are not and will not be deposits with or liabilities of Macquarie Bank Limited ABN 46 008 583 542 and its holding companies, including their subsidiaries or related companies (Macquarie Group), and are subject to investment risk, including possible delays in repayment and loss of income and capital invested. No Macquarie Group company guarantees or will guarantee the performance of the Fund, the repayment of capital from the Fund, or any particular rate of return.

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.

Industry risk — The risk that the value of securities in a particular industry (such as financial services or manufacturing) will decline because of changing expectations for the performance of that industry.

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.

High yield (junk bond) 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; and greater price volatility and risk of loss of income and principal than are higher-rated securities. High yield bonds are sometimes issued by municipalities with less financial strength and therefore have less ability to make projected debt payments on the bonds.

Interest rate risk — The risk that securities will decrease in value if interest rates rise. This risk is generally associated with bonds.

Loans and other 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.

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.

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.

Risk Lose Money [Text]

rr_RiskLoseMoney

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.

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

How has Delaware Dividend Income Fund performed?

Performance Narrative [Text Block]

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.

Bar Chart [Heading]

rr_BarChartHeading

Year-by-year total return (Class A)

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the periods illustrated in this bar chart, Class A's highest quarterly return was 15.58% for the quarter ended June 30, 2009 and its lowest quarterly return was -18.93% 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.

Performance Table Heading

rr_PerformanceTableHeading

Average annual total returns for periods ended December 31, 2014

Performance Table Closing [Text Block]

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.

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 Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

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

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 Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

delawareinvestments.com/performance

Performance Availability Phone [Text]

rr_PerformanceAvailabilityPhone

800 523-1918

(Delaware Dividend Income Fund) | S&P 500® Index (reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

1 Year

rr_AverageAnnualReturnYear01

13.69%

5 Years

rr_AverageAnnualReturnYear05

15.45%

10 Years

rr_AverageAnnualReturnYear10

7.67%

(Delaware Dividend Income Fund) | Class A

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) imposed on purchases as a percentage of offering price

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

5.75%

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

0.64%

Distribution and service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

0.25%

Other expenses

rr_OtherExpensesOverAssets

0.21%

Total annual fund operating expenses

rr_ExpensesOverAssets

1.10%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

681

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

905

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

1,146

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

1,838

Annual Return 2005

rr_AnnualReturn2005

2.66%

Annual Return 2006

rr_AnnualReturn2006

19.65%

Annual Return 2007

rr_AnnualReturn2007

(3.93%)

Annual Return 2008

rr_AnnualReturn2008

(32.48%)

Annual Return 2009

rr_AnnualReturn2009

36.43%

Annual Return 2010

rr_AnnualReturn2010

13.50%

Annual Return 2011

rr_AnnualReturn2011

2.08%

Annual Return 2012

rr_AnnualReturn2012

13.65%

Annual Return 2013

rr_AnnualReturn2013

19.70%

Annual Return 2014

rr_AnnualReturn2014

7.88%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

highest quarterly return was 15.58% for the quarter ended June 30, 2009

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

15.58%

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Jun. 30, 2009

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

lowest quarterly return was -18.93% for the quarter ended Dec. 31, 2008

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(18.93%)

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Dec. 31, 2008

1 Year

rr_AverageAnnualReturnYear01

1.68%

5 Years

rr_AverageAnnualReturnYear05

9.89%

10 Years

rr_AverageAnnualReturnYear10

5.71%

(Delaware Dividend Income Fund) | Class A | return after taxes on distributions

Risk/Return:

rr_RiskReturnAbstract

1 Year

rr_AverageAnnualReturnYear01

0.90%

5 Years

rr_AverageAnnualReturnYear05

8.92%

10 Years

rr_AverageAnnualReturnYear10

4.49%

(Delaware Dividend Income Fund) | Class A | return after taxes on distributions and sale of Fund shares

Risk/Return:

rr_RiskReturnAbstract

1 Year

rr_AverageAnnualReturnYear01

1.27%

5 Years

rr_AverageAnnualReturnYear05

7.52%

10 Years

rr_AverageAnnualReturnYear10

4.10%

(Delaware Dividend Income Fund) | Class C

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) imposed on purchases as a percentage 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%

^[1]

Management fees

rr_ManagementFeesOverAssets

0.64%

Distribution and service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

1.00%

Other expenses

rr_OtherExpensesOverAssets

0.21%

Total annual fund operating expenses

rr_ExpensesOverAssets

1.85%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

288

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

582

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

1,001

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

2,169

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

188

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

582

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

1,001

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

2,169

1 Year

rr_AverageAnnualReturnYear01

6.07%

5 Years

rr_AverageAnnualReturnYear05

10.38%

10 Years

rr_AverageAnnualReturnYear10

5.54%

(Delaware Dividend Income Fund) | Class R

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) imposed on purchases as a percentage 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

0.64%

Distribution and service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

0.50%

Other expenses

rr_OtherExpensesOverAssets

0.21%

Total annual fund operating expenses

rr_ExpensesOverAssets

1.35%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

137

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

428

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

739

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

1,624

1 Year

rr_AverageAnnualReturnYear01

7.61%

5 Years

rr_AverageAnnualReturnYear05

10.93%

10 Years

rr_AverageAnnualReturnYear10

6.06%

(Delaware Dividend Income Fund) | Institutional Class

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) imposed on purchases as a percentage 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

0.64%

Distribution and service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.21%

Total annual fund operating expenses

rr_ExpensesOverAssets

0.85%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

87

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

271

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

471

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

1,049

1 Year

rr_AverageAnnualReturnYear01

8.22%

5 Years

rr_AverageAnnualReturnYear05

11.50%

10 Years

rr_AverageAnnualReturnYear10

6.61%

(Delaware Small Cap Core Fund)

Risk/Return:

rr_RiskReturnAbstract

Objective [Heading]

rr_ObjectiveHeading

What is the Fund's investment objective?

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

Delaware Small Cap Core Fund seeks long-term capital appreciation.

Expense [Heading]

rr_ExpenseHeading

What are the Fund's fees and expenses?

Expense Narrative [Text Block]

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 advisor, 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 Discounts [Text]

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 advisor, 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

50,000

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

Shareholder fees (fees paid directly from your investment)

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

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

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

Expense Example Narrative [Text Block]

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:

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

Portfolio turnover

Portfolio Turnover [Text Block]

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 the 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 30% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

30.00%

Strategy [Heading]

rr_StrategyHeading

What are the Fund's principal investment strategies?

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

The Fund invests primarily in stocks of small companies that its investment manager, Delaware Management Company (Manager), believes have a combination of attractive valuations, growth prospects, and strong cash flows. Under normal circumstances, at least 80% of the Fund's net assets, plus the amount of any borrowings for investment purposes, will be in investments of small-capitalization companies (80% policy). The Fund considers small-capitalization companies to be companies within the market capitalization range of the Russell 2000® Index at the time of purchase.

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.

Risk [Heading]

rr_RiskHeading

What are the principal risks of investing in the Fund?

Risk Narrative [Text Block]

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:

Investments not guaranteed by Delaware Management Company (Manager) or its affiliates — Investments in the Fund are not and will not be deposits with or liabilities of Macquarie Bank Limited ABN 46 008 583 542 and its holding companies, including their subsidiaries or related companies (Macquarie Group), and are subject to investment risk, including possible delays in repayment and loss of income and capital invested. No Macquarie Group company guarantees or will guarantee the performance of the Fund, the repayment of capital from the Fund, or any particular rate of return.

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.

Industry risk — The risk that the value of securities in a particular industry (such as financial services or manufacturing) will decline because of changing expectations for the performance of that industry.

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.

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.

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

Counterparty risk — The risk that a counterparty to a derivatives contract (such as a swap, 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).

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.

Risk Lose Money [Text]

rr_RiskLoseMoney

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.

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

How has Delaware Small Cap Core Fund performed?

Performance Narrative [Text Block]

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 or lifetime periods compare with those of a broad measure of market performance. Prior to Aug. 1, 2005, the Fund had not engaged in a broad distribution effort of its shares and had been subject to limited redemption requests. 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.

Bar Chart [Heading]

rr_BarChartHeading

Year-by-year total return (Class A)

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the periods illustrated in this bar chart, Class A's highest quarterly return was 20.77% for the quarter ended June 30, 2009 and its lowest quarterly return was -26.16% 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.

Performance Table Heading

rr_PerformanceTableHeading

Average annual total returns for periods ended December 31, 2014

Performance Table Closing [Text Block]

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.

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 Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

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

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 Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

delawareinvestments.com/performance

Performance Availability Phone [Text]

rr_PerformanceAvailabilityPhone

800 523-1918

(Delaware Small Cap Core Fund) | Russell 2000 Index (reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

1 Year

rr_AverageAnnualReturnYear01

4.89%

5 Years

rr_AverageAnnualReturnYear05

15.55%

10 Years

rr_AverageAnnualReturnYear10

7.77%

(Delaware Small Cap Core Fund) | Class A

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) imposed on purchases as a percentage of offering price

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

5.75%

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%

Distribution and service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

0.25%

Other expenses

rr_OtherExpensesOverAssets

0.32%

Total annual fund operating expenses

rr_ExpensesOverAssets

1.32%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

702

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

969

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

1,257

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

2,074

Annual Return 2005

rr_AnnualReturn2005

5.26%

Annual Return 2006

rr_AnnualReturn2006

16.87%

Annual Return 2007

rr_AnnualReturn2007

(4.76%)

Annual Return 2008

rr_AnnualReturn2008

(35.24%)

Annual Return 2009

rr_AnnualReturn2009

26.95%

Annual Return 2010

rr_AnnualReturn2010

28.49%

Annual Return 2011

rr_AnnualReturn2011

0.33%

Annual Return 2012

rr_AnnualReturn2012

15.30%

Annual Return 2013

rr_AnnualReturn2013

42.86%

Annual Return 2014

rr_AnnualReturn2014

8.58%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

highest quarterly return was 20.77% for the quarter ended June 30, 2009

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

20.77%

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Jun. 30, 2009

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

lowest quarterly return was -26.16% for the quarter ended Dec. 31, 2008

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(26.16%)

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Dec. 31, 2008

1 Year

rr_AverageAnnualReturnYear01

2.36%

5 Years

rr_AverageAnnualReturnYear05

16.80%

10 Years

rr_AverageAnnualReturnYear10

7.66%

(Delaware Small Cap Core Fund) | Class A | return after taxes on distributions

Risk/Return:

rr_RiskReturnAbstract

1 Year

rr_AverageAnnualReturnYear01

1.09%

5 Years

rr_AverageAnnualReturnYear05

16.36%

10 Years

rr_AverageAnnualReturnYear10

7.23%

(Delaware Small Cap Core Fund) | Class A | return after taxes on distributions and sale of Fund shares

Risk/Return:

rr_RiskReturnAbstract

1 Year

rr_AverageAnnualReturnYear01

2.34%

5 Years

rr_AverageAnnualReturnYear05

13.62%

10 Years

rr_AverageAnnualReturnYear10

6.16%

(Delaware Small Cap Core Fund) | Class C

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) imposed on purchases as a percentage 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%

^[1]

Management fees

rr_ManagementFeesOverAssets

0.75%

Distribution and service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

1.00%

Other expenses

rr_OtherExpensesOverAssets

0.32%

Total annual fund operating expenses

rr_ExpensesOverAssets

2.07%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

310

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

649

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

1,114

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

2,400

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

210

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

649

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

1,114

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

2,400

Label

rr_AverageAnnualReturnLabel

(lifetime: 8/1/05–12/31/14)

1 Year

rr_AverageAnnualReturnYear01

6.74%

5 Years

rr_AverageAnnualReturnYear05

17.30%

Lifetime

rr_AverageAnnualReturnSinceInception

7.19%

(Delaware Small Cap Core Fund) | Class R

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) imposed on purchases as a percentage 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%

Distribution and service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

0.50%

Other expenses

rr_OtherExpensesOverAssets

0.32%

Total annual fund operating expenses

rr_ExpensesOverAssets

1.57%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

160

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

496

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

855

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

1,867

Label

rr_AverageAnnualReturnLabel

(lifetime: 8/1/05–12/31/14)

1 Year

rr_AverageAnnualReturnYear01

8.25%

5 Years

rr_AverageAnnualReturnYear05

17.89%

Lifetime

rr_AverageAnnualReturnSinceInception

7.73%

(Delaware Small Cap Core Fund) | Institutional Class

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) imposed on purchases as a percentage 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%

Distribution and service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.32%

Total annual fund operating expenses

rr_ExpensesOverAssets

1.07%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

109

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

340

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

590

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

1,306

1 Year

rr_AverageAnnualReturnYear01

8.84%

5 Years

rr_AverageAnnualReturnYear05

18.47%

10 Years

rr_AverageAnnualReturnYear10

8.56%

(Delaware Small Cap Value Fund)

Risk/Return:

rr_RiskReturnAbstract

Objective [Heading]

rr_ObjectiveHeading

What is the Fund's investment objective?

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

Delaware Small Cap Value Fund seeks capital appreciation.

Expense [Heading]

rr_ExpenseHeading

What are the Fund's fees and expenses?

Expense Narrative [Text Block]

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 advisor, 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 Discounts [Text]

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 advisor, 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

50,000

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

Shareholder fees (fees paid directly from your investment)

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

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

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

Expense Example Narrative [Text Block]

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:

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

Portfolio turnover

Portfolio Turnover [Text Block]

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 the 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 17% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

17.00%

Strategy [Heading]

rr_StrategyHeading

What are the Fund's principal investment strategies?

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

The Fund invests primarily in investments of small companies whose stock prices, in the portfolio managers' opinion, appear low relative to their underlying value or future potential. Among other factors, the Fund's investment manager, Delaware Management Company (Manager), considers the financial strength of a company, its management, the prospects for its industry, and any anticipated changes within the company that might suggest a more favorable outlook going forward. The Manager focuses on free cash flow in its individual stock selection, seeking companies that it believes have a sustainable ability to buy back shares, lower debt, and/or increase or initiate dividends. Under normal circumstances, at least 80% of the Fund's net assets, plus the amount of any borrowings for investment purposes, will be in investments of small-capitalization companies (80% policy). The Fund considers small-capitalization companies to be companies with a market capitalization generally less than 3.5 times the dollar-weighted, median market capitalization of the Russell 2000® Index at the time of purchase. The Fund may invest up to 15% of its net assets in real estate investment trusts (REITs).

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.

Risk [Heading]

rr_RiskHeading

What are the principal risks of investing in the Fund?

Risk Narrative [Text Block]

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:

Investments not guaranteed by Delaware Management Company (Manager) or its affiliates — Investments in the Fund are not and will not be deposits with or liabilities of Macquarie Bank Limited ABN 46 008 583 542 and its holding companies, including their subsidiaries or related companies (Macquarie Group), and are subject to investment risk, including possible delays in repayment and loss of income and capital invested. No Macquarie Group company guarantees or will guarantee the performance of the Fund, the repayment of capital from the Fund, or any particular rate of return.

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.

Industry risk — The risk that the value of securities in a particular industry (such as financial services or manufacturing) will decline because of changing expectations for the performance of that industry.

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.

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.

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.

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

Counterparty risk — The risk that a counterparty to a derivatives contract (such as a swap, 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).

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.

Risk Lose Money [Text]

rr_RiskLoseMoney

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.

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

How has Delaware Small Cap Value Fund performed?

Performance Narrative [Text Block]

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.

Bar Chart [Heading]

rr_BarChartHeading

Year-by-year total return (Class A)

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the periods illustrated in this bar chart, Class A's highest quarterly return was 22.78% for the quarter ended Sept. 30, 2009 and its lowest quarterly return was -24.77% 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.

Performance Table Heading

rr_PerformanceTableHeading

Average annual total returns for periods ended December 31, 2014

Performance Table Closing [Text Block]

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.

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 Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

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

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 Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

delawareinvestments.com/performance

Performance Availability Phone [Text]

rr_PerformanceAvailabilityPhone

800 523-1918

(Delaware Small Cap Value Fund) | Russell 2000® Value Index (reflects no deduction for fees, expenses, or taxes)

Risk/Return:

rr_RiskReturnAbstract

1 Year

rr_AverageAnnualReturnYear01

4.22%

5 Years

rr_AverageAnnualReturnYear05

14.26%

10 Years

rr_AverageAnnualReturnYear10

6.89%

(Delaware Small Cap Value Fund) | Class A

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) imposed on purchases as a percentage of offering price

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

5.75%

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

0.68%

Distribution and service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

0.25%

Other expenses

rr_OtherExpensesOverAssets

0.29%

Total annual fund operating expenses

rr_ExpensesOverAssets

1.22%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

692

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

940

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

1,207

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

1,967

Annual Return 2005

rr_AnnualReturn2005

8.61%

Annual Return 2006

rr_AnnualReturn2006

15.35%

Annual Return 2007

rr_AnnualReturn2007

(7.45%)

Annual Return 2008

rr_AnnualReturn2008

(30.51%)

Annual Return 2009

rr_AnnualReturn2009

31.99%

Annual Return 2010

rr_AnnualReturn2010

30.95%

Annual Return 2011

rr_AnnualReturn2011

(1.15%)

Annual Return 2012

rr_AnnualReturn2012

13.08%

Annual Return 2013

rr_AnnualReturn2013

32.18%

Annual Return 2014

rr_AnnualReturn2014

5.37%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

highest quarterly return was 22.78% for the quarter ended Sept. 30, 2009

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

22.78%

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Sep. 30, 2009

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

lowest quarterly return was -24.77% for the quarter ended Dec. 31, 2008

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(24.77%)

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Dec. 31, 2008

1 Year

rr_AverageAnnualReturnYear01

(0.68%)

5 Years

rr_AverageAnnualReturnYear05

13.95%

10 Years

rr_AverageAnnualReturnYear10

7.41%

(Delaware Small Cap Value Fund) | Class A | return after taxes on distributions

Risk/Return:

rr_RiskReturnAbstract

1 Year

rr_AverageAnnualReturnYear01

(1.88%)

5 Years

rr_AverageAnnualReturnYear05

13.35%

10 Years

rr_AverageAnnualReturnYear10

6.68%

(Delaware Small Cap Value Fund) | Class A | return after taxes on distributions and sale of Fund shares

Risk/Return:

rr_RiskReturnAbstract

1 Year

rr_AverageAnnualReturnYear01

0.59%

5 Years

rr_AverageAnnualReturnYear05

11.24%

10 Years

rr_AverageAnnualReturnYear10

5.98%

(Delaware Small Cap Value Fund) | Class C

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) imposed on purchases as a percentage 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%

^[1]

Management fees

rr_ManagementFeesOverAssets

0.68%

Distribution and service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

1.00%

Other expenses

rr_OtherExpensesOverAssets

0.29%

Total annual fund operating expenses

rr_ExpensesOverAssets

1.97%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

300

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

618

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

1,062

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

2,296

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

200

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

618

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

1,062

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

2,296

1 Year

rr_AverageAnnualReturnYear01

3.61%

5 Years

rr_AverageAnnualReturnYear05

14.46%

10 Years

rr_AverageAnnualReturnYear10

7.25%

(Delaware Small Cap Value Fund) | Class R

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) imposed on purchases as a percentage 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

0.68%

Distribution and service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

0.50%

Other expenses

rr_OtherExpensesOverAssets

0.29%

Total annual fund operating expenses

rr_ExpensesOverAssets

1.47%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

150

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

465

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

803

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

1,757

1 Year

rr_AverageAnnualReturnYear01

5.12%

5 Years

rr_AverageAnnualReturnYear05

15.03%

10 Years

rr_AverageAnnualReturnYear10

7.78%

(Delaware Small Cap Value Fund) | Institutional Class

Risk/Return:

rr_RiskReturnAbstract

Maximum sales charge (load) imposed on purchases as a percentage 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

0.68%

Distribution and service (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other expenses

rr_OtherExpensesOverAssets

0.29%

Total annual fund operating expenses

rr_ExpensesOverAssets

0.97%

Expense Example, with Redemption, 1 Year

rr_ExpenseExampleYear01

99

Expense Example, with Redemption, 3 Years

rr_ExpenseExampleYear03

309

Expense Example, with Redemption, 5 Years

rr_ExpenseExampleYear05

536

Expense Example, with Redemption, 10 Years

rr_ExpenseExampleYear10

$ 1,190

1 Year

rr_AverageAnnualReturnYear01

5.64%

5 Years

rr_AverageAnnualReturnYear05

15.60%

10 Years

rr_AverageAnnualReturnYear10

8.33%

[1] Class C shares redeemed within one year of purchase are subject to a 1.00% contingent deferred sales charge (CDSC).