2.3.0.15 Html 85 101 1 true 44 0 false 2 true true R1.htm 0100000 - Document - Risk/Return Summary - Fidelity Corporate Bond Fund {Unlabeled} Sheet http://fidelity.com/role/RiskReturnSummaryFidelityCorporateBondFund Risk/Return Summary - Fidelity Corporate Bond Fund false true R2.htm 0100001 - Document - Risk/Return Summary - Fidelity Corporate Bond Fund (Class A, T and C) {Unlabeled} Sheet http://fidelity.com/role/RiskReturnSummaryFidelityCorporateBondFundClassTAndC Risk/Return Summary - Fidelity Corporate Bond Fund (Class A, T and C) false true R3.htm 0100002 - Document - Risk/Return Summary - Fidelity Corporate Bond Fund (Institutional Class) {Unlabeled} Sheet http://fidelity.com/role/RiskReturnSummaryFidelityCorporateBondFundInstitutionalClass Risk/Return Summary - Fidelity Corporate Bond Fund (Institutional Class) false true R4.htm 0100003 - Document - Risk/Return Summary - Fidelity Conservative Income Bond Fund {Unlabeled} Sheet http://fidelity.com/role/RiskReturnSummaryFidelityConservativeIncomeBondFund Risk/Return Summary - Fidelity Conservative Income Bond Fund false true R5.htm 0100004 - Document - Risk/Return Summary - Fidelity Conservative Income Bond Fund (Institutional Class) {Unlabeled} Sheet http://fidelity.com/role/RiskReturnSummaryFidelityConservativeIncomeBondFundInstitutionalClass Risk/Return Summary - Fidelity Conservative Income Bond Fund (Institutional Class) false true R6.htm 0100005 - Document - Risk/Return Summary - Fidelity Intermediate Bond Fund {Unlabeled} Sheet http://fidelity.com/role/RiskReturnSummaryFidelityIntermediateBondFund Risk/Return Summary - Fidelity Intermediate Bond Fund false true R7.htm 0100006 - Document - Risk/Return Summary - Fidelity Investment Grade Bond Fund {Unlabeled} Sheet http://fidelity.com/role/RiskReturnSummaryFidelityInvestmentGradeBondFund Risk/Return Summary - Fidelity Investment Grade Bond Fund false true R8.htm 0100007 - Document - Risk/Return Summary - Fidelity Short-Term Bond Fund {Unlabeled} Sheet http://fidelity.com/role/RiskReturnSummaryFidelityShortTermBondFund Risk/Return Summary - Fidelity Short-Term Bond Fund false true R9.htm 0100008 - Document - Risk/Return Summary - Fidelity Series Investment Grade Bond Fund {Unlabeled} Sheet http://fidelity.com/role/RiskReturnSummaryFidelitySeriesInvestmentGradeBondFund Risk/Return Summary - Fidelity Series Investment Grade Bond Fund false true R10.htm 0100009 - Document - Risk/Return Summary - Fidelity Series Investment Grade Bond Fund (Class F) {Unlabeled} Sheet http://fidelity.com/role/RiskReturnSummaryFidelitySeriesInvestmentGradeBondFundClassF Risk/Return Summary - Fidelity Series Investment Grade Bond Fund (Class F) false true R11.htm 0100010 - Document - Risk/Return Summary - Fidelity Short-Term Bond Fund (Class F) {Unlabeled} Sheet http://fidelity.com/role/RiskReturnSummaryFidelityShortTermBondFundClassF Risk/Return Summary - Fidelity Short-Term Bond Fund (Class F) false true R12.htm 0100011 - Document - Risk/Return Summary - Fidelity Investment Grade Bond Fund (Class A, T, B and C) {Unlabeled} Sheet http://fidelity.com/role/RiskReturnSummaryFidelityInvestmentGradeBondFundClassTBAndC Risk/Return Summary - Fidelity Investment Grade Bond Fund (Class A, T, B and C) false true R13.htm 0100012 - Document - Risk/Return Summary - Fidelity Investment Grade Bond Fund (Institutional Class) {Unlabeled} Sheet http://fidelity.com/role/RiskReturnSummaryFidelityInvestmentGradeBondFundInstitutionalClass Risk/Return Summary - Fidelity Investment Grade Bond Fund (Institutional Class) false true R14.htm 0100113 - Document - Risk/Return Summary - Spartan U.S. Bond Index Fund (Investor and Fidelity Advantage Class) {Unlabeled} Sheet http://fidelity.com/role/RiskReturnSummarySpartanUSBondIndexFundInvestorFidelityAdvantageClass Risk/Return Summary - Spartan U.S. Bond Index Fund (Investor and Fidelity Advantage Class) false true R15.htm 0100114 - Document - Risk/Return Summary - Spartan U.S. Bond Index Fund (Class F) {Unlabeled} Sheet http://fidelity.com/role/RiskReturnSummarySpartanUSBondIndexFundClassF Risk/Return Summary - Spartan U.S. Bond Index Fund (Class F) false true R16.htm 0100115 - Document - Risk/Return Summary - Spartan U.S. Bond Index Fund (Institutional and Fidelity Advantage Institutional Class) {Unlabeled} Sheet http://fidelity.com/role/RiskReturnSummarySpartanUSBondIndexFundInstitutionalFidelityAdvantageInstitutionalClass Risk/Return Summary - Spartan U.S. Bond Index Fund (Institutional and Fidelity Advantage Institutional Class) false false R89.htm 040000 - Disclosure - Risk/Return Detail Data {Elements} Sheet http://xbrl.sec.gov/rr/role/RiskReturnDetailData Risk/Return Detail Data false false All Reports Book All Reports fsst35315-20111029.xml fsst35315-20111029.xsd fsst35315-20111029_cal.xml fsst35315-20111029_def.xml fsst35315-20111029_lab.xml fsst35315-20111029_pre.xml BarChart1.jpg BarChart2.jpg BarChart3.jpg BarChart4.jpg BarChart5.jpg BarChart6.jpg BarChart7.jpg BarChart8.jpg BarChart9.jpg BarChart10.jpg BarChart11.jpg true true