2.2.0.25truefalse020010 - Schedule - Shareholder Feestruefalsefalse1falsefalseUSDtruefalse{dei_LegalEntityAxis} : S000003912 Member {rr_ProspectusShareClassAxis} : C000010961 Member 4/15/2011 - 4/15/2011 USD ($) $c_S000003912_C000010961_AAAAhttp://www.sec.gov/CIK0000910682duration2011-04-15T00:00:002011-04-15T00:00:00falsefalseDelaware U.S. Growth Funddei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldidelaware_S000003912Memberdei_LegalEntityAxisexplicitMemberfalsefalseClass Arr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldidelaware_C000010961Memberrr_ProspectusShareClassAxisexplicitMemberRatioStandardhttp://www.xbrl.org/2003/instancepurexbrli0USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$1false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://xbrl.sec.gov/rr/role/shareholderfeesdata1falsefalsefalse00falsefalsefalsefalsefalse1falsefalseUSDtruefalse{dei_LegalEntityAxis} : S000003912 Member {rr_ProspectusShareClassAxis} : C000010961 Member 4/15/2011 - 4/15/2011 USD ($) $c_S000003912_C000010961_AAAAhttp://www.sec.gov/CIK0000910682duration2011-04-15T00:00:002011-04-15T00:00:00falsefalseDelaware U.S. Growth Funddei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldidelaware_S000003912Memberdei_LegalEntityAxisexplicitMemberfalsefalseClass Arr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldidelaware_C000010961Memberrr_ProspectusShareClassAxisexplicitMemberRatioStandardhttp://www.xbrl.org/2003/instancepurexbrli0USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalseClass A2true0rr_ShareholderFeesAbstractrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseShareholder Fees:3false0rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPricerrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.05750.0575falsefalsefalsefalsefalseOtherrr:NonNegativePure4TypepureMaximum Deferred Sales Charge (Load) (as a percentage of ____) A.3.instructions.2.a.i "Maximum Deferred Sales Charge (Load)" includes the maximum total deferred sales charge (load) payable upon redemption, in installments, or both, expressed as a percentage of the amount or amounts stated in response to Item 7(a), except that, for a sales charge (load) based on net asset value at the time of purchase, show the sales charge (load) as a percentage of the offering price at the time of purchase. A Fund may include in a footnote to the table, if applicable, a tabular presentation showing the amount of deferred sales charges (loads) over time or a narrative explanation of the sales charges (loads) (e.g., __% in the first year after purchase, declining to __% in the __ year and eliminated thereafter). A.3.instructions.2.a.ii If more than one type of sales charge (load) is imposed (e.g., a deferred sales charge (load) and a front-end sales charge (load)), the first caption in the table should read "Maximum Sales Charge (Load)" and show the maximum cumulative percentage. Show the percentage amounts and the terms of each sales charge (load) comprising that figure on separate lines below.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 1 -Subsection table falsefalseMaximum sales charge (load) imposed on purchases as a percentage of offering price4false0rr_MaximumDeferredSalesChargeOverOfferingPricerrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue00falsefalsefalsefalsefalseOtherrr:NonNegativePure4TypepureMaximum Deferred Sales Charge (Load) (as a percentage of ____) A.3.instructions.2.a.i "Maximum Deferred Sales Charge (Load)" includes the maximum total deferred sales charge (load) payable upon redemption, in installments, or both, expressed as a percentage of the amount or amounts stated in response to Item 7(a), except that, for a sales charge (load) based on net asset value at the time of purchase, show the sales charge (load) as a percentage of the offering price at the time of purchase. A Fund may include in a footnote to the table, if applicable, a tabular presentation showing the amount of deferred sales charges (loads) over time or a narrative explanation of the sales charges (loads) (e.g., __% in the first year after purchase, declining to __% in the __ year and eliminated thereafter). A.3.instructions.2.a.ii If more than one type of sales charge (load) is imposed (e.g., a deferred sales charge (load) and a front-end sales charge (load)), the first caption in the table should read "Maximum Sales Charge (Load)" and show the maximum cumulative percentage. Show the percentage amounts and the terms of each sales charge (load) comprising that figure on separate lines below.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 2 -Subparagraph a -Clause i -Subsection instructions falsefalseMaximum contingent deferred sales charge (load) as a percentage of original purchase price or redemption price, whichever is lower5false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://xbrl.sec.gov/rr/role/shareholderfeesdata1falsefalsefalse00falsefalsefalsefalsefalse2falsefalseUSDtruefalse{dei_LegalEntityAxis} : S000003912 Member {rr_ProspectusShareClassAxis} : C000010962 Member 4/15/2011 - 4/15/2011 USD ($) $c_S000003912_C000010962_AAAAhttp://www.sec.gov/CIK0000910682duration2011-04-15T00:00:002011-04-15T00:00:00falsefalseDelaware U.S. Growth Funddei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldidelaware_S000003912Memberdei_LegalEntityAxisexplicitMemberfalsefalseClass Brr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldidelaware_C000010962Memberrr_ProspectusShareClassAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170RatioStandardhttp://www.xbrl.org/2003/instancepurexbrli0USDUSD$OthernaNo definition available.No authoritative reference available.falsefalseClass B6true0rr_ShareholderFeesAbstractrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseShareholder Fees:7false0rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPricerrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue00falsefalsefalsefalsefalseOtherrr:NonNegativePure4TypepureMaximum Deferred Sales Charge (Load) (as a percentage of ____) A.3.instructions.2.a.i "Maximum Deferred Sales Charge (Load)" includes the maximum total deferred sales charge (load) payable upon redemption, in installments, or both, expressed as a percentage of the amount or amounts stated in response to Item 7(a), except that, for a sales charge (load) based on net asset value at the time of purchase, show the sales charge (load) as a percentage of the offering price at the time of purchase. A Fund may include in a footnote to the table, if applicable, a tabular presentation showing the amount of deferred sales charges (loads) over time or a narrative explanation of the sales charges (loads) (e.g., __% in the first year after purchase, declining to __% in the __ year and eliminated thereafter). A.3.instructions.2.a.ii If more than one type of sales charge (load) is imposed (e.g., a deferred sales charge (load) and a front-end sales charge (load)), the first caption in the table should read "Maximum Sales Charge (Load)" and show the maximum cumulative percentage. Show the percentage amounts and the terms of each sales charge (load) comprising that figure on separate lines below.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 1 -Subsection table falsefalseMaximum sales charge (load) imposed on purchases as a percentage of offering price8false0rr_MaximumDeferredSalesChargeOverOfferingPricerrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.040.04[1]falsefalsefalsefalsefalseOtherrr:NonNegativePure4TypepureMaximum Deferred Sales Charge (Load) (as a percentage of ____) A.3.instructions.2.a.i "Maximum Deferred Sales Charge (Load)" includes the maximum total deferred sales charge (load) payable upon redemption, in installments, or both, expressed as a percentage of the amount or amounts stated in response to Item 7(a), except that, for a sales charge (load) based on net asset value at the time of purchase, show the sales charge (load) as a percentage of the offering price at the time of purchase. A Fund may include in a footnote to the table, if applicable, a tabular presentation showing the amount of deferred sales charges (loads) over time or a narrative explanation of the sales charges (loads) (e.g., __% in the first year after purchase, declining to __% in the __ year and eliminated thereafter). A.3.instructions.2.a.ii If more than one type of sales charge (load) is imposed (e.g., a deferred sales charge (load) and a front-end sales charge (load)), the first caption in the table should read "Maximum Sales Charge (Load)" and show the maximum cumulative percentage. Show the percentage amounts and the terms of each sales charge (load) comprising that figure on separate lines below.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 2 -Subparagraph a -Clause i -Subsection instructions falsefalseMaximum contingent deferred sales charge (load) as a percentage of original purchase price or redemption price, whichever is lower9false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://xbrl.sec.gov/rr/role/shareholderfeesdata1falsefalsefalse00falsefalsefalsefalsefalse3falsefalseUSDtruefalse{dei_LegalEntityAxis} : S000003912 Member {rr_ProspectusShareClassAxis} : C000010963 Member 4/15/2011 - 4/15/2011 USD ($) $c_S000003912_C000010963_AAAAhttp://www.sec.gov/CIK0000910682duration2011-04-15T00:00:002011-04-15T00:00:00falsefalseDelaware U.S. Growth Funddei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldidelaware_S000003912Memberdei_LegalEntityAxisexplicitMemberfalsefalseClass Crr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldidelaware_C000010963Memberrr_ProspectusShareClassAxisexplicitMemberRatioStandardhttp://www.xbrl.org/2003/instancepurexbrli0USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalseClass C10true0rr_ShareholderFeesAbstractrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseShareholder Fees:11false0rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPricerrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue00falsefalsefalsefalsefalseOtherrr:NonNegativePure4TypepureMaximum Deferred Sales Charge (Load) (as a percentage of ____) A.3.instructions.2.a.i "Maximum Deferred Sales Charge (Load)" includes the maximum total deferred sales charge (load) payable upon redemption, in installments, or both, expressed as a percentage of the amount or amounts stated in response to Item 7(a), except that, for a sales charge (load) based on net asset value at the time of purchase, show the sales charge (load) as a percentage of the offering price at the time of purchase. A Fund may include in a footnote to the table, if applicable, a tabular presentation showing the amount of deferred sales charges (loads) over time or a narrative explanation of the sales charges (loads) (e.g., __% in the first year after purchase, declining to __% in the __ year and eliminated thereafter). A.3.instructions.2.a.ii If more than one type of sales charge (load) is imposed (e.g., a deferred sales charge (load) and a front-end sales charge (load)), the first caption in the table should read "Maximum Sales Charge (Load)" and show the maximum cumulative percentage. Show the percentage amounts and the terms of each sales charge (load) comprising that figure on separate lines below.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 1 -Subsection table falsefalseMaximum sales charge (load) imposed on purchases as a percentage of offering price12false0rr_MaximumDeferredSalesChargeOverOfferingPricerrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.010.01[1]falsefalsefalsefalsefalseOtherrr:NonNegativePure4TypepureMaximum Deferred Sales Charge (Load) (as a percentage of ____) A.3.instructions.2.a.i "Maximum Deferred Sales Charge (Load)" includes the maximum total deferred sales charge (load) payable upon redemption, in installments, or both, expressed as a percentage of the amount or amounts stated in response to Item 7(a), except that, for a sales charge (load) based on net asset value at the time of purchase, show the sales charge (load) as a percentage of the offering price at the time of purchase. A Fund may include in a footnote to the table, if applicable, a tabular presentation showing the amount of deferred sales charges (loads) over time or a narrative explanation of the sales charges (loads) (e.g., __% in the first year after purchase, declining to __% in the __ year and eliminated thereafter). A.3.instructions.2.a.ii If more than one type of sales charge (load) is imposed (e.g., a deferred sales charge (load) and a front-end sales charge (load)), the first caption in the table should read "Maximum Sales Charge (Load)" and show the maximum cumulative percentage. Show the percentage amounts and the terms of each sales charge (load) comprising that figure on separate lines below.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 2 -Subparagraph a -Clause i -Subsection instructions falsefalseMaximum contingent deferred sales charge (load) as a percentage of original purchase price or redemption price, whichever is lower13false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://xbrl.sec.gov/rr/role/shareholderfeesdata1falsefalsefalse00falsefalsefalsefalsefalse4falsefalseUSDtruefalse{dei_LegalEntityAxis} : S000003912 Member {rr_ProspectusShareClassAxis} : C000010964 Member 4/15/2011 - 4/15/2011 USD ($) $c_S000003912_C000010964_AAAAhttp://www.sec.gov/CIK0000910682duration2011-04-15T00:00:002011-04-15T00:00:00falsefalseDelaware U.S. Growth Funddei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldidelaware_S000003912Memberdei_LegalEntityAxisexplicitMemberfalsefalseClass Rrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldidelaware_C000010964Memberrr_ProspectusShareClassAxisexplicitMemberRatioStandardhttp://www.xbrl.org/2003/instancepurexbrli0USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalseClass R14true0rr_ShareholderFeesAbstractrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseShareholder Fees:15false0rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPricerrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue00falsefalsefalsefalsefalseOtherrr:NonNegativePure4TypepureMaximum Deferred Sales Charge (Load) (as a percentage of ____) A.3.instructions.2.a.i "Maximum Deferred Sales Charge (Load)" includes the maximum total deferred sales charge (load) payable upon redemption, in installments, or both, expressed as a percentage of the amount or amounts stated in response to Item 7(a), except that, for a sales charge (load) based on net asset value at the time of purchase, show the sales charge (load) as a percentage of the offering price at the time of purchase. A Fund may include in a footnote to the table, if applicable, a tabular presentation showing the amount of deferred sales charges (loads) over time or a narrative explanation of the sales charges (loads) (e.g., __% in the first year after purchase, declining to __% in the __ year and eliminated thereafter). A.3.instructions.2.a.ii If more than one type of sales charge (load) is imposed (e.g., a deferred sales charge (load) and a front-end sales charge (load)), the first caption in the table should read "Maximum Sales Charge (Load)" and show the maximum cumulative percentage. Show the percentage amounts and the terms of each sales charge (load) comprising that figure on separate lines below.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 1 -Subsection table falsefalseMaximum sales charge (load) imposed on purchases as a percentage of offering price16false0rr_MaximumDeferredSalesChargeOverOfferingPricerrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue00falsefalsefalsefalsefalseOtherrr:NonNegativePure4TypepureMaximum Deferred Sales Charge (Load) (as a percentage of ____) A.3.instructions.2.a.i "Maximum Deferred Sales Charge (Load)" includes the maximum total deferred sales charge (load) payable upon redemption, in installments, or both, expressed as a percentage of the amount or amounts stated in response to Item 7(a), except that, for a sales charge (load) based on net asset value at the time of purchase, show the sales charge (load) as a percentage of the offering price at the time of purchase. A Fund may include in a footnote to the table, if applicable, a tabular presentation showing the amount of deferred sales charges (loads) over time or a narrative explanation of the sales charges (loads) (e.g., __% in the first year after purchase, declining to __% in the __ year and eliminated thereafter). A.3.instructions.2.a.ii If more than one type of sales charge (load) is imposed (e.g., a deferred sales charge (load) and a front-end sales charge (load)), the first caption in the table should read "Maximum Sales Charge (Load)" and show the maximum cumulative percentage. Show the percentage amounts and the terms of each sales charge (load) comprising that figure on separate lines below.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 2 -Subparagraph a -Clause i -Subsection instructions falsefalseMaximum contingent deferred sales charge (load) as a percentage of original purchase price or redemption price, whichever is lower1 <p style="font-size:12;padding-top:2;padding-bottom:0;padding-left:0;">If you redeem Class B shares during the first year after you buy them, you will pay a contingent deferred sales charge (CDSC) of 4.00%, which declines to 3.25% during the second year, 2.75% during the third year, 2.25% during the fourth and fifth years, 1.50% during the sixth year, and 0% thereafter. Class C shares redeemed within one year of purchase are subject to a 1.00% CDSC.</p> 116Shareholder Fees (Delaware U.S. Growth Fund)UnKnownUnKnownUnKnownUnKnowntruetrue