2.4.0.8020007 - Document - Risk/Return Summary {Unlabeled} - Institutional Class Prospectus - Gold and Precious Metals Fundfalsefalsetrue1false falsefalsedoc_Institutional_Class_ProspectusMember_S000004783Memberhttp://www.sec.gov/CIK0000101507duration2013-03-31T00:00:002013-03-31T00:00:001false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00Institutional Class Prospectus | Gold and Precious Metals Fundfalsefalsefalse1false truefalsedoc_Institutional_Class_ProspectusMember_S000004783Memberhttp://www.sec.gov/CIK0000101507duration2013-03-31T00:00:002013-03-31T00:00:00falsefalseck0000101507_doc_Institutional_Class_ProspectusMemberdei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldick0000101507_doc_Institutional_Class_ProspectusMemberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalseck0000101507_S000004783Memberdei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldick0000101507_S000004783Memberdei_LegalEntityAxisexplicitMembernanafalse0Institutional Class Prospectus | Gold and Precious Metals Fund2false 4rr_RiskReturnHeadingrr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Gold and Precious Metals Fundfalsefalsefalsexbrli:stringItemTypestringRisk/Return Summary Investment Objectives/Goals Include the following information, in plain English under rule 421(d) under the Securities Act, in the order and subject matter indicatedReference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 false0Risk/Return [Heading]3false 4rr_ObjectiveHeadingrr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Investment Objectivefalsefalsefalsexbrli:stringItemTypestringInvestment Objectives/Goals. Disclose the Fund's investment objectives or goals. A Fund also may identify its type or category (e.g., that it is a Money Market Fund or a balanced fund).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 -Subsection a false0Objective [Heading]4false 4rr_ObjectivePrimaryTextBlockrr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00 The Gold and Precious Metals Fund seeks long-term growth of capital plus protection against inflation and monetary instability.falsefalsefalsenonnum:textBlockItemTypenaInvestment Objectives/Goals. Disclose the Fund's investment objectives or goals. A Fund also may identify its type or category (e.g., that it is a Money Market Fund or a balanced fund).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 -Subsection a false0Objective, Primary [Text Block]5false 4rr_ObjectiveSecondaryTextBlockrr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The fund also pursues current income as a secondary objective. falsefalsefalsenonnum:textBlockItemTypenaInvestment Objectives/Goals. Disclose the Fund's investment objectives or goals. A Fund also may identify its type or category (e.g., that it is a Money Market Fund or a balanced fund).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 -Subsection a false0Objective, Secondary [Text Block]6false 4rr_ExpenseHeadingrr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Fees and Expenses of the Fundfalsefalsefalsexbrli:stringItemTypestringRisk/Return Summary Fee Table Includes the following information, in plain English under rule 421(d) under the Securities Act, after Item 2 Fees and expenses of the Fund This table describes the fees and expenses that you may pay if you buy and hold shared 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 $[_____] in [name of fund family] funds. Shareholder Fees (fees paid directly from your investment) 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 you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be You would pay the following expenses if you did not redeem your shares The Example does not reflect sales charges (loads) on reinvested dividends [and other distributions]. If these sales charges (loads) were included, your costs would be higher. 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 may indicate higher transaction costs. 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 __% of the average value of its whole portfolio. Instructions. A.3.instructions.6 New Funds. For purposes of this Item, a "New Fund" is a Fund that does not include in Form N-1A financial statements reporting operating results or that includes financial statements for the Fund's initial fiscal year reporting operating results for a period of 6 months or less. The following Instructions apply to New Funds.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Subsection instructions -Paragraph 1 -Subparagraph d false0Expense [Heading]7false 4rr_ExpenseNarrativeTextBlockrr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00 The following table describes the fees and expenses that you may pay if you buy and hold Institutional Class shares of the fund. falsefalsefalsenonnum:textBlockItemTypenaThis table describes the fees and expenses that you may pay if you buy and hold shared 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 $[_____] in [name of fund family] funds. Include the narrative explanations in the order indicated. A Fund may modify the narrative explanations if the explanation contains comparable information to that shown. The narrative explanation regarding sales charge discounts is only required by a Fund that offers such discounts and should specify the minimum level of investment required to qualify for a discount. Modify the narrative explanation to state that Fund shares are sold on a national securities exchange at the end of the time periods indicated, and that brokerage commissions for buying and selling Fund shares through a broker are not reflected.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Subsection instructions -Paragraph 1 -Subparagraph b false0Expense Narrative [Text Block]8false 4rr_ShareholderFeesCaptionrr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Shareholder Fees (fees paid directly from your investment)falsefalsefalsexbrli:stringItemTypestringShareholder Fees (fees paid directly from your investment).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Subsection table -Paragraph 1 false0Shareholder Fees Caption [Text]9false 4rr_ShareholderFeesTableTextBlockrr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00~ http://usglobal.com/20130809/role/ScheduleShareholderFees20008 column dei_DocumentInformationDocumentAxis compact ck0000101507_doc_Institutional_Class_ProspectusMember column dei_LegalEntityAxis compact ck0000101507_S000004783Member row primary compact * ~falsefalse~ http://usglobal.com/20130809/role/ScheduleShareholderFees20008 column dei_DocumentInformationDocumentAxis compact ck0000101507_doc_Institutional_Class_ProspectusMember column dei_LegalEntityAxis compact ck0000101507_S000004783Member row primary compact * ~falsehttp://usglobal.com/20130809/role/ScheduleShareholderFees20008020008 - Schedule - Shareholder Feestruefalsefalse1falseColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxisck0000101507_doc_Institutional_Class_ProspectusMemberColumndei_LegalEntityAxisAxisck0000101507_S000004783MemberColumnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*duration2013-03-31T00:00:002013-03-31T00:00:00falsefalseInstitutional Class Prospectusdei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldick0000101507_doc_Institutional_Class_ProspectusMemberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalseGold and Precious Metals Funddei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldick0000101507_S000004783Memberdei_LegalEntityAxisexplicitMemberfalsefalseInstitutional Class Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldick0000101507_C000130162Memberrr_ProspectusShareClassAxisexplicitMemberInstitutional Class ProspectusGold and Precious Metals FundInstitutional Class SharespureStandardhttp://www.xbrl.org/2003/instancepurexbrli0Standard0 USDfalsefalseduration2013-03-31T00:00:002013-03-31T00:00:00$1falseRowprimaryElement*3false 4rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPricerr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalselabelrr: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: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Subsection table -Paragraph 1 -Subparagraph 1 false0Maximum sales charge 0rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPricerr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalselabel1truetruetrue0.00000.0000falsefalsefalserr: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: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Subsection table -Paragraph 1 -Subparagraph 1 false0Maximum sales charge2falseRowprimaryElement*4false 4rr_RedemptionFeeOverRedemptionrr_falsenadurationfalsefalsefalsefalsefalsefalsefalsetruenegatedTerseLabelrr:NonPositivePure4Typepure"Redemption Fee" (as a percentage of amount redeemed, if applicable) If the Fund is an Exchange-Traded Fund and issues or redeems shares in creation units of not less than 25,000 shares each, exclude any fees charged for the purchase and redemption of the Fund's creation units. "Redemption Fee" includes a fee charged for any redemption of the Fund's shares, but does not include a deferred sales charge (load) imposed upon redemption.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Subsection instructions -Paragraph 2 -Subparagraph b false0Redemption fee (as a percentage of amount redeemed, as applicable, on fund shares held 7 days or less) 0rr_RedemptionFeeOverRedemptionrr_falsenadurationfalsefalsefalsefalsefalsefalsefalsetruenegatedTerseLabel1truetruetrue0.00050.0005falsefalsefalserr:NonPositivePure4Typepure"Redemption Fee" (as a percentage of amount redeemed, if applicable) If the Fund is an Exchange-Traded Fund and issues or redeems shares in creation units of not less than 25,000 shares each, exclude any fees charged for the purchase and redemption of the Fund's creation units. "Redemption Fee" includes a fee charged for any redemption of the Fund's shares, but does not include a deferred sales charge (load) imposed upon redemption.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Subsection instructions -Paragraph 2 -Subparagraph b false0Redemption fee (as a percentage of amount redeemed, as applicable, on fund shares held 7 days or less)falseShareholder Fees UnKnownUnKnownUnKnownUnKnownfalsefalsefalseSheet12011207ColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxisck0000101507_doc_Institutional_Class_ProspectusMemberColumndei_LegalEntityAxisAxisck0000101507_S000004783MemberColumnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*RowprimaryElement*falsenonnum:textBlockItemTypenaContains a command for the SEC Viewer for the role corresponding to ShareholderFeesData.No definition available.false0Shareholder Fees [Table]10false 4rr_OperatingExpensesCaptionrr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)falsefalsefalsexbrli:stringItemTypestringAnnual Fund Operating Expenses (ongoing expenses that you pay each year as a percentage of the value of your investment)Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Subsection table -Paragraph 1 -Subparagraph 7 false0Operating Expenses Caption [Text]11false 4rr_AnnualFundOperatingExpensesTableTextBlockrr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00~ http://usglobal.com/20130809/role/ScheduleAnnualFundOperatingExpenses20009 column dei_DocumentInformationDocumentAxis compact ck0000101507_doc_Institutional_Class_ProspectusMember column dei_LegalEntityAxis compact ck0000101507_S000004783Member row primary compact * ~falsefalse~ http://usglobal.com/20130809/role/ScheduleAnnualFundOperatingExpenses20009 column dei_DocumentInformationDocumentAxis compact ck0000101507_doc_Institutional_Class_ProspectusMember column dei_LegalEntityAxis compact ck0000101507_S000004783Member row primary compact * ~falsehttp://usglobal.com/20130809/role/ScheduleAnnualFundOperatingExpenses20009020009 - Schedule - Annual Fund Operating Expensestruefalsefalse1falseColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxisck0000101507_doc_Institutional_Class_ProspectusMemberColumndei_LegalEntityAxisAxisck0000101507_S000004783MemberColumnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*duration2013-03-31T00:00:002013-03-31T00:00:00falsefalseInstitutional Class Prospectusdei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldick0000101507_doc_Institutional_Class_ProspectusMemberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalseGold and Precious Metals Funddei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldick0000101507_S000004783Memberdei_LegalEntityAxisexplicitMemberfalsefalseInstitutional Class Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldick0000101507_C000130162Memberrr_ProspectusShareClassAxisexplicitMemberInstitutional Class ProspectusGold and Precious Metals FundInstitutional Class SharespureStandardhttp://www.xbrl.org/2003/instancepurexbrli0Standard0 USDfalsefalseduration2013-03-31T00:00:002013-03-31T00:00:00$1falseRowprimaryElement*3false 4rr_ManagementFeesOverAssetsrr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalselabelrr:NonNegativePure4TypepureManagement Fees include investment advisory fees (including any fees based on the Fund's performance), any other management fees payable to the investment adviser or its affiliates, and administrative fees payable to the investment adviser or its affiliates that are not included as "Other Expenses."Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Subsection instructions -Paragraph 3 -Subparagraph a false0Management fee 0rr_ManagementFeesOverAssetsrr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalselabel[1]1truetruetrue0.00900.0090falsefalsefalserr:NonNegativePure4TypepureManagement Fees include investment advisory fees (including any fees based on the Fund's performance), any other management fees payable to the investment adviser or its affiliates, and administrative fees payable to the investment adviser or its affiliates that are not included as "Other Expenses."Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Subsection instructions -Paragraph 3 -Subparagraph a false0Management fee2falseRowprimaryElement*4false 4rr_DistributionAndService12b1FeesOverAssetsrr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalselabelrr:NonNegativePure4TypepureDistribution [and/or Service] (12b-1) Fees" include all distribution or other expenses incurred during the most recent fiscal year under a plan adopted pursuant to rule 12b-1 [17 CFR 270.12b-1]. Under an appropriate caption or a subcaption of "Other Expenses," disclose the amount of any distribution or similar expenses deducted from the Fund's assets other than pursuant to a rule 12b-1 plan.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Subsection table -Paragraph 1 -Subparagraph 9 false0Distribution and/or service (12b-1) fees 0rr_DistributionAndService12b1FeesOverAssetsrr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalselabel1truetruetrue0.00000.0000falsefalsefalserr:NonNegativePure4TypepureDistribution [and/or Service] (12b-1) Fees" include all distribution or other expenses incurred during the most recent fiscal year under a plan adopted pursuant to rule 12b-1 [17 CFR 270.12b-1]. Under an appropriate caption or a subcaption of "Other Expenses," disclose the amount of any distribution or similar expenses deducted from the Fund's assets other than pursuant to a rule 12b-1 plan.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Subsection table -Paragraph 1 -Subparagraph 9 false0Distribution and/or service (12b-1) fees3falseRowprimaryElement*5false 4rr_OtherExpensesOverAssetsrr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalselabelrr:NonNegativePure4Typepure"Other Expenses" include all expenses not otherwise disclosed in the table that are deducted from the Fund's assets or charged to all shareholder accounts. The amount of expenses deducted from the Fund's assets are the amounts shown as expenses in the Fund's statement of operations (including increases resulting from complying with paragraph 2(g) of rule 6-07 of Regulation S-X [17 CFR 210.6-07]). "Other Expenses" do not include extraordinary expenses as determined under generally accepted accounting principles (see Accounting Principles Board Opinion No. 30). If extraordinary expenses were incurred that materially affected the Fund's "Other Expenses," disclose in a footnote to the table what "Other Expenses" would have been had the extraordinary expenses been included.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Subsection instructions -Paragraph 3 -Subparagraph c -Clause i false0Other expenses 0rr_OtherExpensesOverAssetsrr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalselabel[2]1truetruetrue0.00570.0057falsefalsefalserr:NonNegativePure4Typepure"Other Expenses" include all expenses not otherwise disclosed in the table that are deducted from the Fund's assets or charged to all shareholder accounts. The amount of expenses deducted from the Fund's assets are the amounts shown as expenses in the Fund's statement of operations (including increases resulting from complying with paragraph 2(g) of rule 6-07 of Regulation S-X [17 CFR 210.6-07]). "Other Expenses" do not include extraordinary expenses as determined under generally accepted accounting principles (see Accounting Principles Board Opinion No. 30). If extraordinary expenses were incurred that materially affected the Fund's "Other Expenses," disclose in a footnote to the table what "Other Expenses" would have been had the extraordinary expenses been included.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Subsection instructions -Paragraph 3 -Subparagraph c -Clause i false0Other expenses4falseRowprimaryElement*6false 4rr_ExpensesOverAssetsrr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalselabelrr:NonNegativePure4TypepureTotal Annual Fund Operating Expenses. If the Fund is a Feeder Fund, reflect the aggregate expenses of the Feeder Fund and the Master Fund in a single fee table using the captions provided. In a footnote to the fee table, state that the table and Example reflect the expenses of both the Feeder and Master Funds. If the prospectus offers more than one Class of a Multiple Class Fund or more than one Feeder Fund that invests in the same Master Fund, provide a separate response for each Class or Feeder Fund. Base the percentages of "Annual Fund Operating Expenses" on amounts incurred during the Fund's most recent fiscal year, but include in expenses amounts that would have been incurred absent expense reimbursement or fee waiver arrangements. If the Fund has changed its fiscal year and, as a result, the most recent fiscal year is less than three months, use the fiscal year prior to the most recent fiscal year as the basis for determining "Annual Fund Operating Expenses."Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Subsection instructions -Paragraph 3 -Subparagraph d false0Total annual fund operating expenses 0rr_ExpensesOverAssetsrr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalselabel1truetruetrue0.01470.0147falsefalsefalserr:NonNegativePure4TypepureTotal Annual Fund Operating Expenses. If the Fund is a Feeder Fund, reflect the aggregate expenses of the Feeder Fund and the Master Fund in a single fee table using the captions provided. In a footnote to the fee table, state that the table and Example reflect the expenses of both the Feeder and Master Funds. If the prospectus offers more than one Class of a Multiple Class Fund or more than one Feeder Fund that invests in the same Master Fund, provide a separate response for each Class or Feeder Fund. Base the percentages of "Annual Fund Operating Expenses" on amounts incurred during the Fund's most recent fiscal year, but include in expenses amounts that would have been incurred absent expense reimbursement or fee waiver arrangements. If the Fund has changed its fiscal year and, as a result, the most recent fiscal year is less than three months, use the fiscal year prior to the most recent fiscal year as the basis for determining "Annual Fund Operating Expenses."Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Subsection instructions -Paragraph 3 -Subparagraph d false0Total annual fund operating expenses1A performance fee adjustment may increase or decrease the management fee by up to +/- 0.25% of the average net assets of the fund during a rolling 12-month period. The performance adjustment is calculated by comparing the performance of the Institutional Class shares of the fund during the relevant performance period to that of the FTSE Gold Mines Index. For purposes of calculating the performance adjustment, the performance will include the performance of the Investor Class shares of the fund for the first 12 months after the commencement of operations of the Institutional Class shares of the fund.2Other expenses are based on estimates for the current fiscal year.falseAnnual Fund Operating Expenses UnKnownUnKnownUnKnownUnKnownfalsefalsefalseSheet14031409ColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxisck0000101507_doc_Institutional_Class_ProspectusMemberColumndei_LegalEntityAxisAxisck0000101507_S000004783MemberColumnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*RowprimaryElement*falsenonnum:textBlockItemTypenaContains a command for the SEC Viewer for the role corresponding to OperatingExpensesData.No definition available.false0Annual Fund Operating Expenses [Table]12false 4rr_ExpenseExampleHeadingrr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Examplefalsefalsefalsexbrli:stringItemTypestringHeading for Expense Example.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Subsection instructions -Paragraph 4 false0Expense Example [Heading]13false 4rr_ExpenseExampleNarrativeTextBlockrr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00 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 Institutional Class of 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% annual return and the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your cost would be: falsefalsefalsenonnum:textBlockItemTypenaThe Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Subsection example -Paragraph 1 -Subparagraph 1 false0Expense Example Narrative [Text Block]14false 4rr_ExpenseExampleWithRedemptionTableTextBlockrr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00~ http://usglobal.com/20130809/role/ScheduleExpenseExampleTransposed20010 column dei_DocumentInformationDocumentAxis compact ck0000101507_doc_Institutional_Class_ProspectusMember column dei_LegalEntityAxis compact ck0000101507_S000004783Member row primary compact * ~falsefalse~ http://usglobal.com/20130809/role/ScheduleExpenseExampleTransposed20010 column dei_DocumentInformationDocumentAxis compact ck0000101507_doc_Institutional_Class_ProspectusMember column dei_LegalEntityAxis compact ck0000101507_S000004783Member row primary compact * ~truehttp://usglobal.com/20130809/role/ScheduleExpenseExampleTransposed20010020010 - Schedule - Expense Example {Transposed}truefalsefalse1falseColumnprimaryElement*3false 4rr_ExpenseExampleYear01rr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabelrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Subsection instructions -Paragraph 4 false21 Year USDfalsefalse$2falseColumnprimaryElement*4false 4rr_ExpenseExampleYear03rr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabelrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Subsection example -Paragraph 1 -Subparagraph 2 false23 Years USDfalsefalse$3falseColumnprimaryElement*5false 4rr_ExpenseExampleYear05rr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabelrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Subsection example -Paragraph 1 -Subparagraph 2 false25 Years USDfalsefalse$4falseColumnprimaryElement*6false 4rr_ExpenseExampleYear10rr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabelrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Subsection example -Paragraph 1 -Subparagraph 2 false210 Years USDfalsefalse$1falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxisck0000101507_doc_Institutional_Class_ProspectusMemberRowdei_LegalEntityAxisAxisck0000101507_S000004783MemberRowrr_ProspectusShareClassAxisAxis*RowunitUnit*duration2013-03-31T00:00:002013-03-31T00:00:00falsefalseInstitutional Class Prospectusdei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldick0000101507_doc_Institutional_Class_ProspectusMemberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalseGold and Precious Metals Funddei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldick0000101507_S000004783Memberdei_LegalEntityAxisexplicitMemberfalsefalseGold and Precious Metals Fundrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldick0000101507_C000012994Memberrr_ProspectusShareClassAxisexplicitMemberInstitutional Class ProspectusGold and Precious Metals FundGold and Precious Metals FundusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170 0truefalsefalsefalsefalsefalsefalsefalsefalse1truefalsetrue150150falsefalsefalse2truefalsetrue465465falsefalsefalse3truefalsetrue803803falsefalsefalse4truefalsetrue17571757falsefalsefalsenanafalse0Institutional Class Prospectus Gold and Precious Metals FundfalseExpense Example (USD $)UnKnownUnKnownUnKnownUnKnownfalsefalsefalseSheet413041024ColumnprimaryElement*RowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxisck0000101507_doc_Institutional_Class_ProspectusMemberRowdei_LegalEntityAxisAxisck0000101507_S000004783MemberRowrr_ProspectusShareClassAxisAxis*RowunitUnit*falsenonnum:textBlockItemTypenaContains a command for the SEC Viewer for the role corresponding to ExpenseExample.No definition available.false0Expense Example, With Redemption [Table]15false 4rr_PortfolioTurnoverHeadingrr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Portfolio Turnoverfalsefalsefalsexbrli:stringItemTypestringDisclose the portfolio turnover rate provided in response to Item 14(a) for the most recent fiscal year (or for such shorter period as the Fund has been in operation). Disclose the period for which the information is provided if less than a full fiscal year. A Fund that is a Money Market Fund may omit the portfolio turnover information required by this Item.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Subsection instructions -Paragraph 5 false0Portfolio Turnover [Heading]16false 4rr_PortfolioTurnoverTextBlockrr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00 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 where 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. The Institutional Class shares of the fund have no operating history. The Investor Class shares of the fund, which are invested in the same portfolio of securities, had a portfolio turnover rate of 95% for the fiscal year ended December 31, 2012. falsefalsefalsenonnum:textBlockItemTypenaDisclose the portfolio turnover rate provided in response to Item 14(a) for the most recent fiscal year (or for such shorter period as the Fund has been in operation). Disclose the period for which the information is provided if less than a full fiscal year. A Fund that is a Money Market Fund may omit the portfolio turnover information required by this Item.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Subsection example -Paragraph 3 false0Portfolio Turnover [Text Block]17false 4rr_StrategyHeadingrr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Principal Investment Strategiesfalsefalsefalsexbrli:stringItemTypestringPrincipal investment strategies of the Fund. Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a false0Strategy [Heading]18false 4rr_StrategyNarrativeTextBlockrr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00 The Adviser uses a matrix of "top-down" macro models and "bottom-up" micro stock selection models to determine weighting in countries, sectors and individual securities. The Adviser believes government policies are a precursor to change, and as a result, it monitors and tracks the fiscal and monetary policies of the world's largest countries both in terms of economic stature and population. The Adviser focuses on historical and socioeconomic cycles, and it applies both statistical and fundamental models, including "growth at a reasonable price" (GARP), to identify companies with superior growth and value metrics. The Adviser overlays these explicit knowledge models with the tacit knowledge obtained by domestic and global travel for first-hand observation of local and geopolitical conditions, as well as specific companies and projects. Under normal market conditions, the Gold and Precious Metals Fund will invest at least 80% of its net assets in equity and equity-related securities of companies principally involved in the mining, fabrication, processing, marketing or distribution of precious metals including gold, silver, platinum group, palladium and diamonds. The fund may invest in these precious metals directly and/or in equity and equity-related securities, such as exchange-traded funds, that represent interests in, or related to, these precious metals. The equity and equity- related securities in which the fund primarily invests are common stocks, preferred stocks, convertible securities, rights and warrants, and depository receipts (ADRs and GDRs). The fund also participates in private placements, initial public offerings (IPOs), and long-term equity anticipation securities (LEAPS). The fund may invest in warrants to gain exposure to individual securities in the gold and precious metals industry over the long term. Warrants allow the fund to imitate a purchase or sale of a stock for a fraction of its price (premium) and hold that option for a long period of time before it expires. The fund may also receive warrants when it participates in a private placement. The issuer of the private placement may provide a warrant as an incentive for investing in the initial financing of the company. The fund focuses on selecting companies with established producing mines that have large deposits that create a significant stream of cash flow. Senior mining companies that have proven reserves are more strongly influenced by the price of gold. Although the fund focuses its investments on senior mining companies, the fund may invest in junior and intermediate mining companies. Junior mining companies typically have small market capitalization and no source of steady cash flow, and their growth generally comes from a major mining discovery. Therefore, the risk and opportunities are substantially greater than investing in a senior mining company with proven reserves. The volatility of these smaller mining companies is typically greater than that of senior producers. The Adviser's stock selection process for established mining companies looks to identify companies with robust growth profiles and strong cash flows. In making security selections for junior and intermediate mining investments, the Adviser looks for companies with proven management who have a strong track record in developing and producing mining companies and whose potential mining assets and financial structure have upside leverage to rising commodity prices. Although the fund has greater latitude to invest its assets in different precious metals, it currently has significant investments in the gold sector. Gold companies include mining companies that exploit gold deposits that are supported by co-products and by-products such as copper, silver, lead and zinc, and also diversified mining companies which produce a meaningful amount of gold. The fund is non-diversified and, therefore, may invest a greater percentage of its assets in a particular issuer in comparison to a diversified fund. The fund also may purchase call and put options, and enter into covered option writing transactions. In addition, the fund may invest up to 15% of its net assets in illiquid securities. The Adviser uses a matrix of statistical models to monitor market volatility and money flows, and as a result, it may at times maintain higher than normal cash levels. For example, the Adviser may take a temporary defensive position when the securities trading markets or the economy are experiencing excessive volatility, a prolonged general decline, or other adverse conditions. falsefalsefalsenonnum:textBlockItemTypenaPrincipal investment strategies of the Fund. Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a false0Strategy Narrative [Text Block]19false 4rr_RiskHeadingrr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Principal Risksfalsefalsefalsexbrli:stringItemTypestringNarrative Risk Disclosure.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection b -Paragraph 1 false0Risk [Heading]20false 4rr_RiskNarrativeTextBlockrr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00 •  Main Risk. As with all mutual funds, loss of money is a risk of investing in the fund. •  Market Risk. The value of the fund's shares will go up and down based on the performance of the companies whose securities it owns and other factors affecting the securities market generally. •  Portfolio Management Risk. The skill of the Adviser will play a significant role in the fund's ability to achieve its investment objectives. There is a risk that the investment strategy does not achieve the fund's objectives or that the Adviser does not implement the strategy properly. •  Foreign Securities Risk/Emerging Markets Risk. The fund's investments in foreign securities are subject to special risks. The fund's returns and share price may be affected to a large degree by several factors, including fluctuations in currency exchange rates; political, social or economic instability; the rule of law with respect to the recognition and protection of property rights; and less stringent accounting, disclosure and financial reporting requirements in a particular country. These risks are generally intensified in emerging markets. The fund's share prices will reflect the movements of the different stock markets in which it is invested and the currencies in which its investments are denominated. •  Industry Concentration Risk. The fund concentrates its investments in gold and other precious metals. The fund may be subject to greater risks and market fluctuations than a portfolio representing a broader range of industries. The fund invests in securities that typically respond to changes in the price of gold and other precious metals, which can be influenced by a variety of global economic, financial, and political factors; increased environmental and labor costs in mining; and changes in laws relating to mining or gold production or sales; and the price may fluctuate substantially over short periods of time. Therefore, the fund may be more volatile than other types of investments. •  Junior and Intermediate Mining Companies Risk. The securities of junior and intermediate exploration gold companies, which are often more speculative in nature, tend to be less liquid and more volatile in price than securities of larger companies. •  Non-Diversification Risk. The fund is non-diversified and may invest a significant portion of its total assets in a small number of companies. This may cause the performance of the fund to be dependent upon the performance of one or more selected companies, which may increase the volatility of the fund. •  Price Volatility Risk. The value of the fund's shares may fluctuate significantly. •  Growth Stock Risk. Growth stocks generally experience share price fluctuations as the market reacts to changing perceptions of the underlying companies' growth potentials and broader economic activities. •  Options Risk. Investing in options, LEAPS (an option that has an expiration date of up to two and one half years), and other instruments with option-type elements may increase the volatility and/or transaction expenses of the fund. An option may expire without value, resulting in a loss of the fund's initial investment and may be less liquid and more volatile than an investment in the underlying securities. •  Warrants Risk. Warrants can provide a greater potential for profit or loss than an equivalent investment in the underlying security. Prices of warrants do not necessarily move, however, in tandem with prices of the underlying securities, particularly for shorter periods of time, and, therefore, may be considered speculative investments. If a warrant held by the fund were not exercised by the date of its expiration, the fund would incur a loss in the amount of the cost of the warrant. •  Restricted Security Risk. The fund may make direct equity investments in securities that are subject to contractual and regulatory restrictions on transfer. These investments may involve a high degree of business and financial risk. The restrictions on transfer may cause the fund to hold a security at a time when it may be beneficial to liquidate the security, and the security could decline significantly in value before the fund could liquidate the security. •  Gold and Precious Metals/Minerals Risk. The fund may invest in gold and precious metals directly and/or in equity and equity-related securities, such as exchange-traded funds that represent interests in, or related to, these precious metals and, therefore, is subject to the risk that it could fail to qualify as a regulated investment company under the Internal Revenue Code if the fund derives more than 10% of its gross income from these investments in gold and precious metals. Failure to qualify as a regulated investment company would result in adverse tax consequences to the fund and its shareholders. •  Illiquidity Risk. Illiquid securities are those securities that cannot be disposed of in seven days or less at approximately the value at which a fund carries them on its balance sheet. These investments may involve a high degree of business and financial risk. falsefalsefalsenonnum:textBlockItemTypenaNarrative Risk Disclosure. A Fund may, in responding to this Item, describe the types of investors for whom the Fund is intended or the types of investment goals that may be consistent with an investment in the Fund.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection b -Paragraph 1 -Subparagraph i -Clause instruction false0Risk Narrative [Text Block]21false 4rr_BarChartAndPerformanceTableHeadingrr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Performance Informationfalsefalsefalsexbrli:stringItemTypestringRisk/Return Bar Chart and Table.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection b -Paragraph 2 false0Bar Chart and Performance Table [Heading]22false 4rr_PerformanceNarrativeTextBlockrr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00 Institutional Class shares have no operating history. The returns shown for all periods are the returns of Investor Class shares of the Fund. Investor Class shares, which are not offered in this prospectus, would have annual returns substantially similar to those of Institutional Class Shares because they are invested in the same portfolio of securities. The returns shown have not been adjusted to reflect any differences in expenses between Institutional Class shares and Investor Class shares. If differences in expenses had been reflected, the returns shown would be higher. The following bar chart and table show the volatility of the fund's Investor Class share returns, which is one indicator of the risks of investing in the fund. The bar charts show changes in the fund's returns from year to year during the period indicated. The table compares the fund's average annual returns for the last 1-, 5- and 10-year periods to those of broad-based securities market indexes. How the fund performed in the past, before and after taxes, is not an indication of how it will perform in the future. You may obtain performance data current to the most recent month end at www.usfunds.com or by calling 1-800-873-8637. falsefalsefalsenonnum:textBlockItemTypenaRisk/Return Bar Chart and Table.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection b -Paragraph 2 false0Performance Narrative [Text Block]23false 4rr_BarChartHeadingrr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Annual Total Returns (as of December 31 each year) Gold and Precious Metals Fundfalsefalsefalsexbrli:stringItemTypestringRisk/Return Bar Chart and Table.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection b -Paragraph 2 false0Bar Chart [Heading]24false 4rr_BarChartTableTextBlockrr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00~ http://usglobal.com/20130809/role/ScheduleAnnualTotalReturnsBarChart20011 column dei_DocumentInformationDocumentAxis compact ck0000101507_doc_Institutional_Class_ProspectusMember column dei_LegalEntityAxis compact ck0000101507_S000004783Member column rr_ProspectusShareClassAxis compact ck0000101507_C000012994Member row primary compact * ~falsefalseBarChart2.jpg~ http://usglobal.com/20130809/role/ScheduleAnnualTotalReturnsBarChart20011 column dei_DocumentInformationDocumentAxis compact ck0000101507_doc_Institutional_Class_ProspectusMember column dei_LegalEntityAxis compact ck0000101507_S000004783Member column rr_ProspectusShareClassAxis compact ck0000101507_C000012994Member row primary compact * ~falsehttp://usglobal.com/20130809/role/ScheduleAnnualTotalReturnsBarChart20011020011 - Schedule - Annual Total Returns [Bar Chart]truefalsefalse1falseColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxisck0000101507_doc_Institutional_Class_ProspectusMemberColumndei_LegalEntityAxisAxisck0000101507_S000004783MemberColumnrr_ProspectusShareClassAxisAxisck0000101507_C000012994MemberColumnunitUnit*duration2013-03-31T00:00:002013-03-31T00:00:00falsefalseInstitutional Class Prospectusdei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldick0000101507_doc_Institutional_Class_ProspectusMemberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalseGold and Precious Metals Funddei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldick0000101507_S000004783Memberdei_LegalEntityAxisexplicitMemberfalsefalseGold and Precious Metals Fundrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldick0000101507_C000012994Memberrr_ProspectusShareClassAxisexplicitMemberInstitutional Class ProspectusGold and Precious Metals FundGold and Precious Metals FundpureStandardhttp://www.xbrl.org/2003/instancepurexbrli0Standard0 USDfalsefalseduration2013-03-31T00:00:002013-03-31T00:00:00$1falseRowprimaryElement*3false3false 4rr_AnnualReturn2003rr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.67080.6708falsefalsefalsexbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection b -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a false0Annual Return 2003 4rr_AnnualReturn2003rr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalsexbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection b -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a false0Annual Return 2003 0rr_AnnualReturn2003rr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.67080.6708falsefalsefalsexbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection b -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a false0Annual Return 20032falseRowprimaryElement*4false4false 4rr_AnnualReturn2004rr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse-0.0644-0.0644falsefalsefalsexbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection b -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a false0Annual Return 2004 4rr_AnnualReturn2004rr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalsexbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection b -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a false0Annual Return 2004 0rr_AnnualReturn2004rr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse-0.0644-0.0644falsefalsefalsexbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection b -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a false0Annual Return 20043falseRowprimaryElement*5false5false 4rr_AnnualReturn2005rr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.32800.3280falsefalsefalsexbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection b -Paragraph 2 -Subparagraph ii false0Annual Return 2005 4rr_AnnualReturn2005rr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalsexbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection b -Paragraph 2 -Subparagraph ii false0Annual Return 2005 0rr_AnnualReturn2005rr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.32800.3280falsefalsefalsexbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection b -Paragraph 2 -Subparagraph ii false0Annual Return 20054falseRowprimaryElement*6false6false 4rr_AnnualReturn2006rr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.50190.5019falsefalsefalsexbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection b -Paragraph 2 -Subparagraph ii false0Annual Return 2006 4rr_AnnualReturn2006rr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalsexbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection b -Paragraph 2 -Subparagraph ii false0Annual Return 2006 0rr_AnnualReturn2006rr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.50190.5019falsefalsefalsexbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection b -Paragraph 2 -Subparagraph ii false0Annual Return 20065falseRowprimaryElement*7false7false 4rr_AnnualReturn2007rr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.16910.1691falsefalsefalsexbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection b -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a false0Annual Return 2007 4rr_AnnualReturn2007rr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalsexbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection b -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a false0Annual Return 2007 0rr_AnnualReturn2007rr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.16910.1691falsefalsefalsexbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection b -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a false0Annual Return 20076falseRowprimaryElement*8false8false 4rr_AnnualReturn2008rr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse-0.2705-0.2705falsefalsefalsexbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection b -Paragraph 2 -Subparagraph ii false0Annual Return 2008 4rr_AnnualReturn2008rr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalsexbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection b -Paragraph 2 -Subparagraph ii false0Annual Return 2008 0rr_AnnualReturn2008rr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse-0.2705-0.2705falsefalsefalsexbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection b -Paragraph 2 -Subparagraph ii false0Annual Return 20087falseRowprimaryElement*9false9false 4rr_AnnualReturn2009rr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.43110.4311falsefalsefalsexbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection b -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a false0Annual Return 2009 4rr_AnnualReturn2009rr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalsexbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection b -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a false0Annual Return 2009 0rr_AnnualReturn2009rr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.43110.4311falsefalsefalsexbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection b -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a false0Annual Return 20098falseRowprimaryElement*10false10false 4rr_AnnualReturn2010rr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.36880.3688falsefalsefalsexbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection b -Paragraph 2 -Subparagraph ii false0Annual Return 2010 4rr_AnnualReturn2010rr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalsexbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection b -Paragraph 2 -Subparagraph ii false0Annual Return 2010 0rr_AnnualReturn2010rr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.36880.3688falsefalsefalsexbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection b -Paragraph 2 -Subparagraph ii false0Annual Return 20109falseRowprimaryElement*11false11false 4rr_AnnualReturn2011rr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse-0.2397-0.2397falsefalsefalsexbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection b -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a false0Annual Return 2011 4rr_AnnualReturn2011rr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalsexbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection b -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a false0Annual Return 2011 0rr_AnnualReturn2011rr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse-0.2397-0.2397falsefalsefalsexbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection b -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a false0Annual Return 201110falseRowprimaryElement*12false12false 4rr_AnnualReturn2012rr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.06440.0644falsefalsefalsexbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection b -Paragraph 2 -Subparagraph ii false0Annual Return 2012 4rr_AnnualReturn2012rr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalsexbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection b -Paragraph 2 -Subparagraph ii false0Annual Return 2012 0rr_AnnualReturn2012rr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.06440.0644falsefalsefalsexbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. 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ProspectusUnKnownUnKnownUnKnownUnKnownfalsefalsefalseSheet35101235057ColumnprimaryElement*RowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxisck0000101507_doc_Institutional_Class_ProspectusMemberRowdei_LegalEntityAxisAxisck0000101507_S000004783MemberRowrr_PerformanceMeasureAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*falsenonnum:textBlockItemTypenaContains a command for the SEC Viewer for the role corresponding to PerformanceTableData.No definition available.false0Performance [Table]28false 4rr_PerformanceTableClosingTextBlockrr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00 After-tax returns are calculated using highest historical individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor's tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts. falsefalsefalsenonnum:textBlockItemTypenaIf the Fund has annual returns for at least one calendar year, provide a table showing the Fund's (A) average annual total return; (B) average annual total return (after taxes on distributions); and (C) average annual total return (after taxes on distributions and redemption). A Money Market Fund should show only the returns described in clause (A) of the preceding sentence. All returns should be shown for 1-, 5-, and 10- calendar year periods ending on the date of the most recently completed calendar year (or for the life of the Fund, if shorter), but only for periods subsequent to the effective date of the Fund's registration statement. The table also should show the returns of an appropriate broad-based securities market index as defined in Instruction 5 to Item 22(b)(7) for the same periods. A Fund that has been in existence for more than 10 years also may include returns for the life of the Fund. A Money Market Fund may provide the Fund's 7-day yield ending on the date of the most recent calendar year or disclose a toll-free (or collect) telephone number that investors can use to obtain the Fund's current 7-day yield. For a Fund (other than a Money Market Fund or a Fund described in General Instruction C.3.(d)(iii)), provide the information in the following table with the specified captions AVERAGE ANNUAL TOTAL RETURNS (For the periods ended December 31, _____)Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection b -Paragraph 2 -Subparagraph iii false0Performance Table Closing [Text Block]falseRisk/Return Summary - Institutional Class Prospectus - Gold and Precious Metals Fund (Institutional Class Prospectus, Gold and Precious Metals Fund)UnKnownUnKnownUnKnownUnKnowntruefalsefalseSheethttp://usglobal.com/20130809/role/DocumentRiskReturnSummaryUnlabeledInstitutionalClassProspectusGoldandPreciousMetalsFund128