2.2.0.25truefalse010000 - Document - Risk/Return Summary {Unlabeled}falsefalsetrue1falsefalsetruefalse{dei_DocumentInformationDocumentAxis} : Spartan Short-Term Treasury Bond Index Fund Fund Summary {dei_LegalEntityAxis} : Spartan Short-Term Treasury Bond Index Fund 3/1/2010 - 2/28/2011 STD-S000017679Memberhttp://www.sec.gov/CIK0000035315duration2010-03-01T00:00:002011-02-28T00:00:00falsefalsefidinv_STD-S000017679Memberdei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldifidinv_STD-S000017679Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalsefidinv_S000017679Memberdei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldifidinv_S000017679Memberdei_LegalEntityAxisexplicitMemberRatioStandardhttp://www.xbrl.org/2003/instancepurexbrli01false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://xbrl.sec.gov/rr/role/riskreturn1falsefalsefalse00Spartan Short-Term Treasury Bond Index Fund Fund Summary | Spartan Short-Term Treasury Bond Index FundSpartan Short-Term Treasury Bond Index Fund Fund Summary | Spartan Short-Term Treasury Bond Index Fundfalsefalsefalsefalsefalse1falsefalsetruefalse{dei_DocumentInformationDocumentAxis} : Spartan Short-Term Treasury Bond Index Fund Fund Summary {dei_LegalEntityAxis} : Spartan Short-Term Treasury Bond Index Fund 3/1/2010 - 2/28/2011 STD-S000017679Memberhttp://www.sec.gov/CIK0000035315duration2010-03-01T00:00:002011-02-28T00:00:00falsefalsefidinv_STD-S000017679Memberdei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldifidinv_STD-S000017679Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalsefidinv_S000017679Memberdei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldifidinv_S000017679Memberdei_LegalEntityAxisexplicitMemberRatioStandardhttp://www.xbrl.org/2003/instancepurexbrli0OthernaNo definition available.No authoritative reference available.falsefalseSpartan Short-Term Treasury Bond Index Fund Fund Summary | Spartan Short-Term Treasury Bond Index Fund3false0rr_RiskReturnHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Fund/Class: Spartan® Short Term Treasury Bond Index Fund/Investor, Fidelity Advantage®falsefalsefalsefalsefalseOtherxbrli: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: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 falsefalseRisk/Return [Heading]4false0rr_ObjectiveHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Investment ObjectivefalsefalsefalsefalsefalseOtherxbrli: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: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 -Subsection a falsefalseObjective [Heading]5false0rr_ObjectivePrimaryTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The fund seeks a high level of current income in a manner consistent with preservation of capital.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringInvestment 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: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 -Subsection a falsefalseObjective, Primary [Text Block]6false0rr_ExpenseHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Fee TablefalsefalsefalsefalsefalseOtherxbrli: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: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph d -Subsection instructions falsefalseExpense [Heading]7false0rr_ExpenseNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The following table describes the fees and expenses that may be incurred when you buy and hold shares of the fund.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringThis 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: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph b -Subsection instructions falsefalseExpense Narrative [Text Block]8false0rr_ShareholderFeesCaptionrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Shareholder fees (fees paid directly from your investment)falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringShareholder Fees (fees paid directly from your investment).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subsection table falsefalseShareholder Fees Caption [Text]9false0rr_ShareholderFeesTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00~ http://xbrl.sec.gov/rr/role/ShareholderFeesData column period compact * column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~falsefalse~ http://xbrl.sec.gov/rr/role/ShareholderFeesData column period compact * column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~falsehttp://xbrl.sec.gov/rr/role/ShareholderFeesDatafalsefalse020010 - Schedule - Shareholder Feestruefalsefalse1falseColumnperiodPeriod*Columndei_LegalEntityAxisAxis*Columnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*duration2010-03-01T00:00:002011-02-28T00:00:00falsefalseSpartan Short-Term Treasury Bond Index Funddei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldifidinv_S000017679Memberdei_LegalEntityAxisexplicitMemberfalsefalseInvestor Classrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldifidinv_C000048849Memberrr_ProspectusShareClassAxisexplicitMemberSpartan Short-Term Treasury Bond Index FundInvestor ClassUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170falseUSDfalsefalse$2falseColumnperiodPeriod*Columndei_LegalEntityAxisAxis*Columnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*duration2010-03-01T00:00:002011-02-28T00:00:00falsefalseSpartan Short-Term Treasury Bond Index Funddei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldifidinv_S000017679Memberdei_LegalEntityAxisexplicitMemberfalsefalseFidelity Advantage Classrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldifidinv_C000048848Memberrr_ProspectusShareClassAxisexplicitMemberSpartan Short-Term Treasury Bond Index FundFidelity Advantage ClassUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170falseUSDfalsefalse$1falseRowprimaryElement*3false0rr_ShareholderFeeOtherrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truefalsetrue10.0010.00falsefalsefalsetruefalse2truefalsetrue10.0010.00falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryOther ExpensesReference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 10 -Subsection table falsefalseAnnual index fund fee (for fund balances under $10,000)0rr_ShareholderFeeOthertruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truefalsetrue10.0010.00falsefalsefalsetruefalse2truefalsetrue10.0010.00falsefalsefalsetruefalseOthernanafalsefalseAnnual index fund fee (for fund balances under $10,000)21Shareholder Fees Spartan Short-Term Treasury Bond Index Fund (USD $)UnKnownUnKnownUnKnownUnKnownfalsetrueColumnperiodPeriod*Columndei_LegalEntityAxisAxis*Columnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*RowprimaryElement*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to ShareholderFeesData.No authoritative reference available.falsefalseShareholder Fees [Table]10false0rr_OperatingExpensesCaptionrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Annual class operating expenses (expenses that you pay each year as a % of the value of your investment)falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringAnnual Fund Operating Expenses (ongoing expenses that you pay each year as a percentage of the value of your investment)Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 7 -Subsection table falsefalseOperating Expenses Caption [Text]11false0rr_AnnualFundOperatingExpensesTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00~ http://xbrl.sec.gov/rr/role/OperatingExpensesData column period compact * column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~falsefalse~ http://xbrl.sec.gov/rr/role/OperatingExpensesData column period compact * column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * row primary compact * ~falsehttp://xbrl.sec.gov/rr/role/OperatingExpensesDatafalsefalse020020 - Schedule - Annual Fund Operating Expensestruefalsefalse1falseColumnperiodPeriod*Columndei_LegalEntityAxisAxis*Columnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*duration2010-03-01T00:00:002011-02-28T00:00:00falsefalseSpartan Short-Term Treasury Bond Index Funddei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldifidinv_S000017679Memberdei_LegalEntityAxisexplicitMemberfalsefalseInvestor Classrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldifidinv_C000048849Memberrr_ProspectusShareClassAxisexplicitMemberSpartan Short-Term Treasury Bond Index FundInvestor ClassUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170falseUSDfalsefalse$2falseColumnperiodPeriod*Columndei_LegalEntityAxisAxis*Columnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*duration2010-03-01T00:00:002011-02-28T00:00:00falsefalseSpartan Short-Term Treasury Bond Index Funddei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldifidinv_S000017679Memberdei_LegalEntityAxisexplicitMemberfalsefalseFidelity Advantage Classrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldifidinv_C000048848Memberrr_ProspectusShareClassAxisexplicitMemberSpartan Short-Term Treasury Bond Index FundFidelity Advantage ClassUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170falseUSDfalsefalse$1falseRowprimaryElement*3false0rr_ManagementFeesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.00100.0010falsefalsefalsetruefalse2truetruetrue0.00100.0010falsefalsefalsetruefalseOtherrr: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: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subparagraph a -Subsection instructions falsefalseManagement fee0rr_ManagementFeesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.00100.0010falsefalsefalsetruefalse2truetruetrue0.00100.0010falsefalsefalsetruefalseOthernanafalsefalseManagement fee2falseRowprimaryElement*4false0rr_DistributionAndService12b1FeesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue00falsefalsefalsetruefalse2truetruetrue00falsefalsefalsetruefalseOtherrr: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: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 9 -Subsection table falsefalseDistribution and/or Service (12b-1) fees0rr_DistributionAndService12b1FeesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue00falsefalsefalsetruefalse2truetruetrue00falsefalsefalsetruefalseOthernanafalsefalseDistribution and/or Service (12b-1) fees3falseRowprimaryElement*5false0rr_OtherExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.00100.0010falsefalsefalsetruefalse2truetruetrue0.00000.0000falsefalsefalsetruefalseOtherrr: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: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subparagraph c -Clause i -Subsection instructions falsefalseOther expenses0rr_OtherExpensesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.00100.0010falsefalsefalsetruefalse2truetruetrue0.00000.0000falsefalsefalsetruefalseOthernanafalsefalseOther expenses4falseRowprimaryElement*6false0rr_ExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.00200.0020falsefalsefalsetruefalse2truetruetrue0.00100.0010falsefalsefalsetruefalseOtherrr: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: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subparagraph d -Subsection instructions falsefalseTotal annual operating expenses0rr_ExpensesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruetrue0.00200.0020falsefalsefalsetruefalse2truetruetrue0.00100.0010falsefalsefalsetruefalseOthernanafalsefalseTotal annual operating expenses24Annual Fund Operating Expenses Spartan Short-Term Treasury Bond Index FundUnKnownUnKnownUnKnownUnKnownfalsetrueColumnperiodPeriod*Columndei_LegalEntityAxisAxis*Columnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*RowprimaryElement*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to OperatingExpensesData.No authoritative reference available.falsefalseAnnual Fund Operating Expenses [Table]12false0rr_ExpenseExampleNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00This example helps compare the cost of investing in the fund with the cost of investing in other mutual funds. Let's say, hypothetically, that the annual return for shares of the fund is 5% and that your shareholder fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringThe 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: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 1 -Subsection example falsefalseExpense Example Narrative [Text Block]13false0rr_ExpenseExampleWithRedemptionTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00~ http://xbrl.sec.gov/rr/role/ExpenseExample row period compact * row primary compact * column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * ~falsefalse~ http://xbrl.sec.gov/rr/role/ExpenseExample row period compact * row primary compact * column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * ~truehttp://xbrl.sec.gov/rr/role/ExpenseExamplefalsefalse020030 - Schedule - Expense Example {Transposed}truefalsefalse1falseColumnperiodPeriod*ColumnprimaryElement*3false0rr_ExpenseExampleYear01rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truefalsetrue2020falsefalsefalsetruefalse2truefalsetrue1010falsefalsefalsetruefalseMonetaryrr: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: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 4 -Subsection instructions falsefalse1 yearduration2010-03-01T00:00:002011-02-28T00:00:00falseUSDfalsefalse$2falseColumnperiodPeriod*ColumnprimaryElement*4false0rr_ExpenseExampleYear03rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truefalsetrue6464falsefalsefalsetruefalse2truefalsetrue3232falsefalsefalsetruefalseMonetaryrr: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: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse3 yearsduration2010-03-01T00:00:002011-02-28T00:00:00falseUSDfalsefalse$3falseColumnperiodPeriod*ColumnprimaryElement*5false0rr_ExpenseExampleYear05rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truefalsetrue113113falsefalsefalsetruefalse2truefalsetrue5656falsefalsefalsetruefalseMonetaryrr: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: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse5 yearsduration2010-03-01T00:00:002011-02-28T00:00:00falseUSDfalsefalse$4falseColumnperiodPeriod*ColumnprimaryElement*6false0rr_ExpenseExampleYear10rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truefalsetrue255255falsefalsefalsetruefalse2truefalsetrue128128falsefalsefalsetruefalseMonetaryrr: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: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse10 yearsduration2010-03-01T00:00:002011-02-28T00:00:00falseUSDfalsefalse$1falseRowdei_LegalEntityAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*falsefalseSpartan Short-Term Treasury Bond Index Funddei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldifidinv_S000017679Memberdei_LegalEntityAxisexplicitMemberfalsefalseInvestor Classrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldifidinv_C000048849Memberrr_ProspectusShareClassAxisexplicitMemberSpartan Short-Term Treasury Bond Index FundInvestor ClassUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso421700truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truefalsetrue2020falsefalsefalsetruefalse2truefalsetrue6464falsefalsefalsetruefalse3truefalsetrue113113falsefalsefalsetruefalse4truefalsetrue255255falsefalsefalsetruefalseOthernanafalsefalseInvestor Class2falseRowdei_LegalEntityAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*falsefalseSpartan Short-Term Treasury Bond Index Funddei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldifidinv_S000017679Memberdei_LegalEntityAxisexplicitMemberfalsefalseFidelity Advantage Classrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldifidinv_C000048848Memberrr_ProspectusShareClassAxisexplicitMemberSpartan Short-Term Treasury Bond Index FundFidelity Advantage ClassUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso421700truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truefalsetrue1010falsefalsefalsetruefalse2truefalsetrue3232falsefalsefalsetruefalse3truefalsetrue5656falsefalsefalsetruefalse4truefalsetrue128128falsefalsefalsetruefalseOthernanafalsefalseFidelity Advantage Class42Expense Example Spartan Short-Term Treasury Bond Index Fund (USD $)UnKnownUnKnownUnKnownUnKnownfalsetrueColumnperiodPeriod*ColumnprimaryElement*Rowdei_LegalEntityAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to ExpenseExample.No authoritative reference available.falsefalseExpense Example, With Redemption [Table]14false0rr_PortfolioTurnoverHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Portfolio TurnoverfalsefalsefalsefalsefalseOtherxbrli: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: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 5 -Subsection instructions falsefalsePortfolio Turnover [Heading]15false0rr_PortfolioTurnoverTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual operating expenses or in the example, affect the fund's performance. During the most recent fiscal year, the fund's portfolio turnover rate was 62% of the average value of its portfolio.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringDisclose 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: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subsection example falsefalsePortfolio Turnover [Text Block]16false0rr_StrategyHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Principal Investment StrategiesfalsefalsefalsefalsefalseOtherxbrli: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: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy [Heading]17false0rr_StrategyNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00• Normally investing at least 80% of assets in securities included in the Barclays Capital® U.S. 1-5 Year Treasury Bond Index (the Index). • Normally maintaining a dollar-weighted average maturity of three years or less. • Using statistical sampling techniques based on duration, maturity, interest rate sensitivity, security structure, and credit quality to attempt to replicate the returns of the Index using a smaller number of securities.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringPrincipal 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: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy Narrative [Text Block]18false0rr_RiskHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Principal Investment RisksfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNarrative Risk Disclosure.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subsection b falsefalseRisk [Heading]19false0rr_RiskNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00• Interest Rate Changes. Interest rate increases can cause the price of a debt security to decrease. • Prepayment. The ability of an issuer of a debt security to repay principal prior to a security's maturity can cause greater price volatility if interest rates change. • Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. A decline in the credit quality of an issuer or a provider of credit support or a maturity-shortening structure for a security can cause the price of a security to decrease. An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. Unlike individual debt securities, which typically pay principal at maturity, the value of an investment in the fund will fluctuate. You could lose money by investing in the fund.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringNarrative 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: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subparagraph i -Clause instruction -Subsection b falsefalseRisk Narrative [Text Block]20false0rr_BarChartAndPerformanceTableHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00PerformancefalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Bar Chart and Table.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subsection b falsefalseBar Chart and Performance Table [Heading]21false0rr_PerformanceNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The following information is intended to help you understand the risks of investing in the fund. The information illustrates the changes in the performance of the fund's shares from year to year and compares the performance of the fund's shares to the performance of a securities market index over various periods of time. The index description appears in the Additional Information about the Indexes section of the prospectus. Past performance (before and after taxes) is not an indication of future performance. Visit www.fidelity.com for updated return information. Year-by-Year Returns falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringRisk/Return Bar Chart and Table.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subsection b falsefalsePerformance Narrative [Text Block]22false0rr_BarChartTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00~ http://xbrl.sec.gov/rr/role/BarChartData column period compact * column primary compact * row dei_LegalEntityAxis compact * row rr_ProspectusShareClassAxis compact * ~falsefalseBarChart4.jpg~ http://xbrl.sec.gov/rr/role/BarChartData column period compact * column primary compact * row dei_LegalEntityAxis compact * row rr_ProspectusShareClassAxis compact * ~falsehttp://xbrl.sec.gov/rr/role/BarChartDatafalsefalse020050 - Schedule - Annual Total Returnstruefalsefalse1falseColumnperiodPeriod*ColumnprimaryElement*Columndei_DocumentInformationDocumentAxisAxis*ColumnunitUnit*3false0rr_AnnualReturnInceptionDaterrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsetruefalse002005-12-20falsefalsetruetruefalseOtherxbrli:dateItemTypedateIf 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. Provide annual total returns beginning with the earliest calendar year. Calculate annual returns using the Instructions to Item 8(a), except that the calculations should be based on calendar years. If a Fund's shares are sold subject to a sales load or account fees, state that sales loads or account fees are not reflected in the bar chart and that, if these amounts were reflected, returns would be less than those shown. 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). When a Multiple Class Fund offering one or more Classes offers a new Class in a prospectus that does not offer the shares of any other Class, include the bar chart with annual total returns for any other existing Class for the first year that the Class is offered. Explain in a footnote that the returns are for a Class that is not offered in the prospectus that would have substantially similar annual returns because the shares are invested in the same portfolio of securities and the annual returns would differ only to the extent that the Classes do not have the same expenses. Include return information for the other Class reflected in the bar chart in the performance table.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalseAnnual Return, Inception Dateduration2010-03-01T00:00:002011-02-28T00:00:00falsefalseSpartan Short-Term Treasury Bond Index Fund Fund Summarydei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldifidinv_STD-S000017679Memberdei_DocumentInformationDocumentAxisexplicitMemberSpartan Short-Term Treasury Bond Index Fund Fund SummaryStandard0falseUSDfalsefalse$2falseColumnperiodPeriod*ColumnprimaryElement*Columndei_DocumentInformationDocumentAxisAxis*ColumnunitUnit*9false0rr_AnnualReturn2006rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.03540.0354falsefalsefalsetruefalseOtherxbrli: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: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalseAnnual Return 2006duration2010-03-01T00:00:002011-02-28T00:00:00falsefalseSpartan Short-Term Treasury Bond Index Fund Fund Summarydei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldifidinv_STD-S000017679Memberdei_DocumentInformationDocumentAxisexplicitMemberSpartan Short-Term Treasury Bond Index Fund Fund SummaryStandard0falseUSDfalsefalse$3falseColumnperiodPeriod*ColumnprimaryElement*Columndei_DocumentInformationDocumentAxisAxis*ColumnunitUnit*10false0rr_AnnualReturn2007rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.07890.0789falsefalsefalsetruefalseOtherxbrli: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: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalseAnnual Return 2007duration2010-03-01T00:00:002011-02-28T00:00:00falsefalseSpartan Short-Term Treasury Bond Index Fund Fund Summarydei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldifidinv_STD-S000017679Memberdei_DocumentInformationDocumentAxisexplicitMemberSpartan Short-Term Treasury Bond Index Fund Fund SummaryStandard0falseUSDfalsefalse$4falseColumnperiodPeriod*ColumnprimaryElement*Columndei_DocumentInformationDocumentAxisAxis*ColumnunitUnit*11false0rr_AnnualReturn2008rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.08710.0871falsefalsefalsetruefalseOtherxbrli: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: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalseAnnual Return 2008duration2010-03-01T00:00:002011-02-28T00:00:00falsefalseSpartan Short-Term Treasury Bond Index Fund Fund Summarydei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldifidinv_STD-S000017679Memberdei_DocumentInformationDocumentAxisexplicitMemberSpartan Short-Term Treasury Bond Index Fund Fund SummaryStandard0falseUSDfalsefalse$5falseColumnperiodPeriod*ColumnprimaryElement*Columndei_DocumentInformationDocumentAxisAxis*ColumnunitUnit*12false0rr_AnnualReturn2009rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse-0.0014-0.0014falsefalsefalsetruefalseOtherxbrli: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: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalseAnnual Return 2009duration2010-03-01T00:00:002011-02-28T00:00:00falsefalseSpartan Short-Term Treasury Bond Index Fund Fund Summarydei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldifidinv_STD-S000017679Memberdei_DocumentInformationDocumentAxisexplicitMemberSpartan Short-Term Treasury Bond Index Fund Fund SummaryStandard0falseUSDfalsefalse$6falseColumnperiodPeriod*ColumnprimaryElement*Columndei_DocumentInformationDocumentAxisAxis*ColumnunitUnit*13false0rr_AnnualReturn2010rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.03500.0350falsefalsefalsetruefalseOtherxbrli: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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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.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalseBar Chart Closing [Text Block]24false0rr_PerformanceTableHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Average Annual ReturnsfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringThis item represents Average Anuual Total Returns. If a Multiple Class Fund offers a Class in the prospectus that converts into another Class after a stated period, compute average annual total returns in the table by using the returns of the other Class for the period after conversion.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit c -Subsection b falsefalsePerformance Table Heading25false0rr_PerformanceTableNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00After-tax returns are calculated using the historical highest individual federal marginal income tax rates, but do not reflect the impact of state or local taxes. After-tax returns for Investor Class are shown in the table below and after-tax returns for other classes will vary. Actual after-tax returns may differ depending on your individual circumstances. The after-tax returns shown are not relevant if you hold your shares in a retirement account or in another tax-deferred arrangement. For the periods ended December 31, 2010falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringIf 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 shouldshow the returns of an appropriate broadbased 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, _____). For a Fund that provides annual total returns for only one calendar year or for a Fund that does not include the bar chart because it does not have annual returns for a full calendar year, modify, as appropriate, the narrative explanation required by paragraph (c)(2)(i) (e.g., by stating that the information gives some indication of the risks of an investment in the Fund by comparing the Fund's performance with a broad measure of market performance).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph iv -Subsection b falsefalsePerformance Table Narrative26false0rr_PerformanceTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00~ http://xbrl.sec.gov/rr/role/PerformanceTableData column dei_LegalEntityAxis compact * column rr_ProspectusShareClassAxis compact * column rr_PerformanceMeasureAxis compact * row primary compact * ~falsefalse~ 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