<?xml version="1.0" encoding="utf-8"?>
<FilingSummary xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
  <Version>2.4.0.6</Version>
  <ProcessingTime />
  <ReportFormat>Html</ReportFormat>
  <ContextCount>25</ContextCount>
  <ElementCount>44</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>true</FootnotesReported>
  <SegmentCount>19</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>2</UnitCount>
  <MyReports>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>000000 - Document - Document and Entity Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fidelity.com/role/DocumentDocumentandEntityInformation</Role>
      <ShortName>Document and Entity Information</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>000011 - Document - Risk/Return Summary {Unlabeled} - Fidelity Municipal Income 2015 Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fidelity.com/role/DocumentRiskReturnSummaryUnlabeledFidelityMunicipalIncome2015Fund</Role>
      <ShortName>Risk/Return Summary  - Fidelity Municipal Income 2015 Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R6.htm</HtmlFileName>
      <LongName>000019 - Disclosure - Risk/Return Detail Data {Elements} - Fidelity Municipal Income 2015 Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fidelity.com/role/DisclosureRiskReturnDetailDataElementsFidelityMunicipalIncome2015Fund</Role>
      <ShortName>Risk/Return Detail Data  - Fidelity Municipal Income 2015 Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>000021 - Document - Risk/Return Summary {Unlabeled} - Fidelity Municipal Income 2017 Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fidelity.com/role/DocumentRiskReturnSummaryUnlabeledFidelityMunicipalIncome2017Fund</Role>
      <ShortName>Risk/Return Summary  - Fidelity Municipal Income 2017 Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>000029 - Disclosure - Risk/Return Detail Data {Elements} - Fidelity Municipal Income 2017 Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fidelity.com/role/DisclosureRiskReturnDetailDataElementsFidelityMunicipalIncome2017Fund</Role>
      <ShortName>Risk/Return Detail Data  - Fidelity Municipal Income 2017 Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>000031 - Document - Risk/Return Summary {Unlabeled} - Fidelity Municipal Income 2019 Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fidelity.com/role/DocumentRiskReturnSummaryUnlabeledFidelityMunicipalIncome2019Fund</Role>
      <ShortName>Risk/Return Summary  - Fidelity Municipal Income 2019 Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>000039 - Disclosure - Risk/Return Detail Data {Elements} - Fidelity Municipal Income 2019 Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fidelity.com/role/DisclosureRiskReturnDetailDataElementsFidelityMunicipalIncome2019Fund</Role>
      <ShortName>Risk/Return Detail Data  - Fidelity Municipal Income 2019 Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>000041 - Document - Risk/Return Summary {Unlabeled} - Fidelity Municipal Income 2021 Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fidelity.com/role/DocumentRiskReturnSummaryUnlabeledFidelityMunicipalIncome2021Fund</Role>
      <ShortName>Risk/Return Summary  - Fidelity Municipal Income 2021 Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R21.htm</HtmlFileName>
      <LongName>000049 - Disclosure - Risk/Return Detail Data {Elements} - Fidelity Municipal Income 2021 Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fidelity.com/role/DisclosureRiskReturnDetailDataElementsFidelityMunicipalIncome2021Fund</Role>
      <ShortName>Risk/Return Detail Data  - Fidelity Municipal Income 2021 Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R22.htm</HtmlFileName>
      <LongName>000051 - Document - Risk/Return Summary {Unlabeled} - Fidelity Municipal Income 2015 Fund A</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fidelity.com/role/DocumentRiskReturnSummaryUnlabeledFidelityMunicipalIncome2015FundA</Role>
      <ShortName>Risk/Return Summary  - Fidelity Municipal Income 2015 Fund A</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>000059 - Disclosure - Risk/Return Detail Data {Elements} - Fidelity Municipal Income 2015 Fund A</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fidelity.com/role/DisclosureRiskReturnDetailDataElementsFidelityMunicipalIncome2015FundA</Role>
      <ShortName>Risk/Return Detail Data  - Fidelity Municipal Income 2015 Fund A</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R27.htm</HtmlFileName>
      <LongName>000061 - Document - Risk/Return Summary {Unlabeled} - Fidelity Municipal Income 2017 Fund A</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fidelity.com/role/DocumentRiskReturnSummaryUnlabeledFidelityMunicipalIncome2017FundA</Role>
      <ShortName>Risk/Return Summary  - Fidelity Municipal Income 2017 Fund A</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R31.htm</HtmlFileName>
      <LongName>000069 - Disclosure - Risk/Return Detail Data {Elements} - Fidelity Municipal Income 2017 Fund A</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fidelity.com/role/DisclosureRiskReturnDetailDataElementsFidelityMunicipalIncome2017FundA</Role>
      <ShortName>Risk/Return Detail Data  - Fidelity Municipal Income 2017 Fund A</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R32.htm</HtmlFileName>
      <LongName>000071 - Document - Risk/Return Summary {Unlabeled} - Fidelity Municipal Income 2019 Fund A</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fidelity.com/role/DocumentRiskReturnSummaryUnlabeledFidelityMunicipalIncome2019FundA</Role>
      <ShortName>Risk/Return Summary  - Fidelity Municipal Income 2019 Fund A</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R36.htm</HtmlFileName>
      <LongName>000079 - Disclosure - Risk/Return Detail Data {Elements} - Fidelity Municipal Income 2019 Fund A</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fidelity.com/role/DisclosureRiskReturnDetailDataElementsFidelityMunicipalIncome2019FundA</Role>
      <ShortName>Risk/Return Detail Data  - Fidelity Municipal Income 2019 Fund A</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R37.htm</HtmlFileName>
      <LongName>000081 - Document - Risk/Return Summary {Unlabeled} - Fidelity Municipal Income 2021 Fund A</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fidelity.com/role/DocumentRiskReturnSummaryUnlabeledFidelityMunicipalIncome2021FundA</Role>
      <ShortName>Risk/Return Summary  - Fidelity Municipal Income 2021 Fund A</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R41.htm</HtmlFileName>
      <LongName>000089 - Disclosure - Risk/Return Detail Data {Elements} - Fidelity Municipal Income 2021 Fund A</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fidelity.com/role/DisclosureRiskReturnDetailDataElementsFidelityMunicipalIncome2021FundA</Role>
      <ShortName>Risk/Return Detail Data  - Fidelity Municipal Income 2021 Fund A</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R42.htm</HtmlFileName>
      <LongName>000091 - Document - Risk/Return Summary {Unlabeled} - Fidelity Municipal Income 2015 Fund Institutional</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fidelity.com/role/DocumentRiskReturnSummaryUnlabeledFidelityMunicipalIncome2015FundInstitutional</Role>
      <ShortName>Risk/Return Summary  - Fidelity Municipal Income 2015 Fund Institutional</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R46.htm</HtmlFileName>
      <LongName>000099 - Disclosure - Risk/Return Detail Data {Elements} - Fidelity Municipal Income 2015 Fund Institutional</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fidelity.com/role/DisclosureRiskReturnDetailDataElementsFidelityMunicipalIncome2015FundInstitutional</Role>
      <ShortName>Risk/Return Detail Data  - Fidelity Municipal Income 2015 Fund Institutional</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R47.htm</HtmlFileName>
      <LongName>000101 - Document - Risk/Return Summary {Unlabeled} - Fidelity Municipal Income 2017 Fund Institutional</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fidelity.com/role/DocumentRiskReturnSummaryUnlabeledFidelityMunicipalIncome2017FundInstitutional</Role>
      <ShortName>Risk/Return Summary  - Fidelity Municipal Income 2017 Fund Institutional</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R51.htm</HtmlFileName>
      <LongName>000109 - Disclosure - Risk/Return Detail Data {Elements} - Fidelity Municipal Income 2017 Fund Institutional</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fidelity.com/role/DisclosureRiskReturnDetailDataElementsFidelityMunicipalIncome2017FundInstitutional</Role>
      <ShortName>Risk/Return Detail Data  - Fidelity Municipal Income 2017 Fund Institutional</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R52.htm</HtmlFileName>
      <LongName>000111 - Document - Risk/Return Summary {Unlabeled} - Fidelity Municipal Income 2019 Fund Institutional</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fidelity.com/role/DocumentRiskReturnSummaryUnlabeledFidelityMunicipalIncome2019FundInstitutional</Role>
      <ShortName>Risk/Return Summary  - Fidelity Municipal Income 2019 Fund Institutional</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R56.htm</HtmlFileName>
      <LongName>000119 - Disclosure - Risk/Return Detail Data {Elements} - Fidelity Municipal Income 2019 Fund Institutional</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fidelity.com/role/DisclosureRiskReturnDetailDataElementsFidelityMunicipalIncome2019FundInstitutional</Role>
      <ShortName>Risk/Return Detail Data  - Fidelity Municipal Income 2019 Fund Institutional</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R57.htm</HtmlFileName>
      <LongName>000121 - Document - Risk/Return Summary {Unlabeled} - Fidelity Municipal Income 2021 Fund Institutional</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fidelity.com/role/DocumentRiskReturnSummaryUnlabeledFidelityMunicipalIncome2021FundInstitutional</Role>
      <ShortName>Risk/Return Summary  - Fidelity Municipal Income 2021 Fund Institutional</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R61.htm</HtmlFileName>
      <LongName>000129 - Disclosure - Risk/Return Detail Data {Elements} - Fidelity Municipal Income 2021 Fund Institutional</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fidelity.com/role/DisclosureRiskReturnDetailDataElementsFidelityMunicipalIncome2021FundInstitutional</Role>
      <ShortName>Risk/Return Detail Data  - Fidelity Municipal Income 2021 Fund Institutional</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R62.htm</HtmlFileName>
      <LongName>040000 - Disclosure - Risk/Return Detail Data {Elements}</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://xbrl.sec.gov/rr/role/RiskReturnDetailData</Role>
      <ShortName>Risk/Return Detail Data</ShortName>
    </Report>
    <Report>
      <IsDefault>true</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <LongName>All Reports</LongName>
      <ReportType>Book</ReportType>
      <ShortName>All Reports</ShortName>
    </Report>
  </MyReports>
  <Logs />
  <InputFiles>
    <File>fsst1-20120828.xml</File>
    <File>fsst1-20120828.xsd</File>
    <File>fsst1-20120828_cal.xml</File>
    <File>fsst1-20120828_def.xml</File>
    <File>fsst1-20120828_lab.xml</File>
    <File>fsst1-20120828_pre.xml</File>
  </InputFiles>
  <SupplementalFiles />
  <BaseTaxonomies />
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
