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    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000235213_ClassMember" id="ixv-134">This semi-annual shareholder report contains information about Fidelity&#xae; SAI Sustainable Conservative Income Municipal Bond Fund for the period February 1, 2024 to July 31, 2024.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000235213_ClassMember" id="ixv-136">semi-annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000235213_ClassMember" id="ixv-141">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-800-544-3455 or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
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    <oef:AddlInfoPhoneNumber contextRef="C000235213_ClassMember" id="ixv-146">1-800-544-3455</oef:AddlInfoPhoneNumber>
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    <oef:ExpensesTextBlock contextRef="C000235213_ClassMember" id="ixv-156">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What were your Fund costs for the last six months?&lt;/span&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(based on hypothetical $10,000 investment)&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:43%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:25%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs of a $10,000 investment&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:31%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs paid as a percentage of a $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:43%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; SAI Sustainable Conservative Income Municipal Bond Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:25%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;10&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:31%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;0.20&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
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      decimals="0"
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      unitRef="usd">10</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000235213_ClassMember"
      decimals="INF"
      id="ixv-143714"
      unitRef="pure">0.0020</oef:ExpenseRatioPct>
    <oef:AddlFundStatisticsTextBlock contextRef="C000235213_ClassMember" id="ixv-197">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;span style="line-height:16px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of July 31, 2024)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;16,369,527&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;107&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Portfolio Turnover&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;68&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
    <us-gaap:AssetsNet
      contextRef="C000235213_InstantMember"
      decimals="0"
      id="ixv-143715"
      unitRef="usd">16369527</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000235213_InstantMember"
      decimals="INF"
      id="ixv-143716"
      unitRef="holding">107</oef:HoldingsCount>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000235213_ClassMember"
      decimals="INF"
      id="ixv-143717"
      unitRef="pure">0.68</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000235213_ClassMember" id="ixv-260">
&#160;

REVENUE SOURCES
 (% of Fund's net assets)


Synthetics

18.4

&#160;


Electric Utilities

15.7

&#160;


Health Care

15.4

&#160;


General Obligations

13.6

&#160;


Housing

9.5

&#160;


Resource Recovery

9.5

&#160;


Education

5.3

&#160;


Others(Individually Less Than 5%)

12.6

&#160;


100.0

&#160;


&#160;




&#160;

AAA

9.5


AA

24.0


A

43.3


BBB

16.9


Not Rated

6.9




QUALITY DIVERSIFICATION (% of Fund's net assets)




Short-Term Investments and Net Other Assets (Liabilities) - (0.6)%*


&#160;


We have used ratings from Moody's Investors Service, Inc. Where Moody's&#xae; ratings are not available, we have used S&amp;P&#xae; ratings. All ratings are as of the date indicated and do not reflect subsequent changes.




&#160;

TOP STATES
(% of Fund's net assets)


New York

11.9


Alabama

10.9


Texas

6.5


Georgia

6.3


Pennsylvania

5.9


&#160;

&#160;




&#160;
</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000235213_RS_0_Member"
      decimals="INF"
      id="ixv-143718"
      unitRef="pure">0.184</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235213_RS_1_Member"
      decimals="INF"
      id="ixv-143719"
      unitRef="pure">0.157</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235213_RS_2_Member"
      decimals="INF"
      id="ixv-143720"
      unitRef="pure">0.154</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235213_RS_3_Member"
      decimals="INF"
      id="ixv-143721"
      unitRef="pure">0.136</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235213_RS_4_Member"
      decimals="INF"
      id="ixv-143722"
      unitRef="pure">0.095</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235213_RS_5_Member"
      decimals="INF"
      id="ixv-143723"
      unitRef="pure">0.095</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235213_RS_6_Member"
      decimals="INF"
      id="ixv-143724"
      unitRef="pure">0.053</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235213_RS_7_Member"
      decimals="INF"
      id="ixv-143725"
      unitRef="pure">0.126</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235213_QD_AAA_Member"
      decimals="INF"
      id="ixv-143726"
      unitRef="pure">0.095</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235213_QD_AA_Member"
      decimals="INF"
      id="ixv-143727"
      unitRef="pure">0.240</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235213_QD_A_Member"
      decimals="INF"
      id="ixv-143728"
      unitRef="pure">0.433</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235213_QD_BBB_Member"
      decimals="INF"
      id="ixv-143729"
      unitRef="pure">0.169</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235213_QD_NotRated_Member"
      decimals="INF"
      id="ixv-143730"
      unitRef="pure">0.069</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235213_TS_0_Member"
      decimals="INF"
      id="ixv-143731"
      unitRef="pure">0.119</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235213_TS_1_Member"
      decimals="INF"
      id="ixv-143732"
      unitRef="pure">0.109</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235213_TS_2_Member"
      decimals="INF"
      id="ixv-143733"
      unitRef="pure">0.065</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235213_TS_3_Member"
      decimals="INF"
      id="ixv-143734"
      unitRef="pure">0.063</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235213_TS_4_Member"
      decimals="INF"
      id="ixv-143735"
      unitRef="pure">0.059</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-514">2024-07-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000131781_ClassMember" id="ixv-526">Fidelity&#xae; Series Large Cap Value Index Fund</oef:FundName>
    <oef:ClassName contextRef="C000131781_ClassMember" id="ixv-529">Fidelity&#xae; Series Large Cap Value Index Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000131781_ClassMember" id="ixv-533">FIOOX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000131781_ClassMember" id="ixv-553">This semi-annual shareholder report contains information about Fidelity&#xae; Series Large Cap Value Index Fund for the period February 1, 2024 to July 31, 2024.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000131781_ClassMember" id="ixv-555">semi-annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000131781_ClassMember" id="ixv-560">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-800-544-8544.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000131781_ClassMember" id="ixv-562">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000131781_ClassMember" id="ixv-565">1-800-544-8544</oef:AddlInfoPhoneNumber>
    <oef:ExpensesTextBlock contextRef="C000131781_ClassMember" id="ixv-572">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What were your Fund costs for the last six months?&lt;/span&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(based on hypothetical $10,000 investment)&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:43%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:25%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs of a $10,000 investment&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:31%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs paid as a percentage of a $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:43%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Series Large Cap Value Index Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:25%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;0&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:6px;color:#000000;font-style:normal;vertical-align:super;font-weight:normal;"&gt;A&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:31%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;0.00&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:6px;color:#000000;font-style:normal;vertical-align:super;font-weight:normal;"&gt;B&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:6px;color:#000000;font-style:normal;vertical-align:super;font-weight:normal;"&gt;A &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans Cd';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Amount represents less than $.50&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:6px;color:#000000;font-style:normal;vertical-align:super;font-weight:normal;"&gt;B &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans Cd';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Amount represents less than 0.005%&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000131781_ClassMember"
      decimals="0"
      id="ixv-143736"
      unitRef="usd">0</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000131781_ClassMember"
      decimals="INF"
      id="ixv-143737"
      unitRef="pure">0.0000</oef:ExpenseRatioPct>
    <oef:AddlFundStatisticsTextBlock contextRef="C000131781_ClassMember" id="ixv-622">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;span style="line-height:16px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of July 31, 2024)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;7,470,689,468&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;877&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Portfolio Turnover&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;42&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
    <us-gaap:AssetsNet
      contextRef="C000131781_InstantMember"
      decimals="0"
      id="ixv-143738"
      unitRef="usd">7470689468</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000131781_InstantMember"
      decimals="INF"
      id="ixv-143739"
      unitRef="holding">877</oef:HoldingsCount>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000131781_ClassMember"
      decimals="INF"
      id="ixv-143740"
      unitRef="pure">0.42</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000131781_ClassMember" id="ixv-685">
&#160;

MARKET SECTORS
(% of Fund's net assets)

&#160;

&#160;


Financials

21.3

&#160;


Health Care

15.8

&#160;


Industrials

14.5

&#160;


Information Technology

9.0

&#160;


Consumer Staples

7.7

&#160;


Energy

7.4

&#160;


Consumer Discretionary

6.1

&#160;


Real Estate

4.7

&#160;


Materials

4.6

&#160;


Utilities

4.5

&#160;


Communication Services

4.1

&#160;


&#160;





Common Stocks

99.7


Short-Term Investments and Net Other Assets (Liabilities)

0.3




ASSET ALLOCATION (% of Fund's net assets)










United States

99.0


Ireland

0.8


Canada

0.1


United Kingdom

0.1


Bermuda

0.0


Belgium

0.0


Puerto Rico

0.0


Brazil

0.0


Luxembourg

0.0




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;


&#160;







</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000131781_MS_FinancialsSectorMember"
      decimals="INF"
      id="ixv-143741"
      unitRef="pure">0.213</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_MS_HealthcareSectorMember"
      decimals="INF"
      id="ixv-143742"
      unitRef="pure">0.158</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_MS_IndustrialSectorMember"
      decimals="INF"
      id="ixv-143743"
      unitRef="pure">0.145</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_MS_InformationTechnologySectorMember"
      decimals="INF"
      id="ixv-143744"
      unitRef="pure">0.090</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_MS_ConsumerStaplesSectorMember"
      decimals="INF"
      id="ixv-143745"
      unitRef="pure">0.077</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_MS_EnergySectorMember"
      decimals="INF"
      id="ixv-143746"
      unitRef="pure">0.074</oef:PctOfNav>
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      contextRef="C000131781_MS_ConsumerDiscretionarySectorMember"
      decimals="INF"
      id="ixv-143747"
      unitRef="pure">0.061</oef:PctOfNav>
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      contextRef="C000131781_MS_RealEstateSectorMember"
      decimals="INF"
      id="ixv-143748"
      unitRef="pure">0.047</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_MS_MaterialsSectorMember"
      decimals="INF"
      id="ixv-143749"
      unitRef="pure">0.046</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_MS_UtilitiesSectorMember"
      decimals="INF"
      id="ixv-143750"
      unitRef="pure">0.045</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_MS_CommunicationsSectorMember"
      decimals="INF"
      id="ixv-143751"
      unitRef="pure">0.041</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_AA_CommonStocks_Member"
      decimals="INF"
      id="ixv-143752"
      unitRef="pure">0.997</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-143753"
      unitRef="pure">0.003</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_GD_US_Member"
      decimals="INF"
      id="ixv-143754"
      unitRef="pure">0.990</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_GD_IE_Member"
      decimals="INF"
      id="ixv-143755"
      unitRef="pure">0.008</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_GD_CA_Member"
      decimals="INF"
      id="ixv-143756"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_GD_GB_Member"
      decimals="INF"
      id="ixv-143757"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_GD_BM_Member"
      decimals="INF"
      id="ixv-143758"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_GD_BE_Member"
      decimals="INF"
      id="ixv-143759"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_GD_PR_Member"
      decimals="INF"
      id="ixv-143760"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_GD_BR_Member"
      decimals="INF"
      id="ixv-143761"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_GD_LU_Member"
      decimals="INF"
      id="ixv-143762"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000131781_ClassMember" id="ixv-914">
TOP HOLDINGS
(% of Fund's net assets)

&#160;

&#160;


Berkshire Hathaway Inc Class B

3.3
&#160;

&#160;


JPMorgan Chase &amp; Co

2.6
&#160;

&#160;


Exxon Mobil Corp

2.3
&#160;

&#160;


UnitedHealth Group Inc

2.1
&#160;

&#160;


Johnson &amp; Johnson

1.7
&#160;

&#160;


Walmart Inc

1.3
&#160;

&#160;


Procter &amp; Gamble Co/The

1.3
&#160;

&#160;


Chevron Corp

1.2
&#160;

&#160;


Bank of America Corp

1.2
&#160;

&#160;


Thermo Fisher Scientific Inc

1.0
&#160;

&#160;


&#160;

18.0

&#160;


&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000131781_TH_0_Member"
      decimals="INF"
      id="ixv-143763"
      unitRef="pure">0.033</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_TH_1_Member"
      decimals="INF"
      id="ixv-143764"
      unitRef="pure">0.026</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_TH_2_Member"
      decimals="INF"
      id="ixv-143765"
      unitRef="pure">0.023</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_TH_3_Member"
      decimals="INF"
      id="ixv-143766"
      unitRef="pure">0.021</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_TH_4_Member"
      decimals="INF"
      id="ixv-143767"
      unitRef="pure">0.017</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_TH_5_Member"
      decimals="INF"
      id="ixv-143768"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_TH_6_Member"
      decimals="INF"
      id="ixv-143769"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_TH_7_Member"
      decimals="INF"
      id="ixv-143770"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_TH_8_Member"
      decimals="INF"
      id="ixv-143771"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000131781_TH_9_Member"
      decimals="INF"
      id="ixv-143772"
      unitRef="pure">0.010</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-1100">2024-07-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000048850_ClassMember" id="ixv-1112">Fidelity&#xae; Tax-Free Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000048850_ClassMember" id="ixv-1115">Fidelity&#xae; Tax-Free Bond Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000048850_ClassMember" id="ixv-1119">FTABX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000048850_ClassMember" id="ixv-1139">This semi-annual shareholder report contains information about Fidelity&#xae; Tax-Free Bond Fund for the period February 1, 2024 to July 31, 2024.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000048850_ClassMember" id="ixv-1141">semi-annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000048850_ClassMember" id="ixv-1146">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-800-544-8544 or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000048850_ClassMember" id="ixv-1148">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000048850_ClassMember" id="ixv-1151">1-800-544-8544</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000048850_ClassMember" id="ixv-1154">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000048850_ClassMember" id="ixv-1161">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What were your Fund costs for the last six months?&lt;/span&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(based on hypothetical $10,000 investment)&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:43%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:25%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs of a $10,000 investment&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:31%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs paid as a percentage of a $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:43%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Tax-Free Bond Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:25%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;12&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:31%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;0.25&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000048850_ClassMember"
      decimals="0"
      id="ixv-143773"
      unitRef="usd">12</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000048850_ClassMember"
      decimals="INF"
      id="ixv-143774"
      unitRef="pure">0.0025</oef:ExpenseRatioPct>
    <oef:AddlFundStatisticsTextBlock contextRef="C000048850_ClassMember" id="ixv-1202">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;span style="line-height:16px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of July 31, 2024)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;3,417,882,452&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;1,288&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Portfolio Turnover&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;6&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
    <us-gaap:AssetsNet
      contextRef="C000048850_InstantMember"
      decimals="0"
      id="ixv-143775"
      unitRef="usd">3417882452</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000048850_InstantMember"
      decimals="INF"
      id="ixv-143776"
      unitRef="holding">1288</oef:HoldingsCount>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000048850_ClassMember"
      decimals="INF"
      id="ixv-143777"
      unitRef="pure">0.06</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000048850_ClassMember" id="ixv-1265">
&#160;

REVENUE SOURCES
 (% of Fund's net assets)


General Obligations

23.0

&#160;


Health Care

22.4

&#160;


Transportation

15.0

&#160;


Special Tax

9.6

&#160;


Education

8.9

&#160;


Electric Utilities

7.0

&#160;


State G.O.

6.0

&#160;


Others(Individually Less Than 5%)

8.1

&#160;


100.0

&#160;


&#160;




&#160;

AAA

5.6


AA

30.5


A

47.4


BBB

9.2


BB

1.1


B

0.5


CCC,CC,C

0.0


Not Rated

4.4


Short-Term Investments and Net Other Assets (Liabilities)

1.3




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;


&#160;


We have used ratings from Moody's Investors Service, Inc. Where Moody's&#xae; ratings are not available, we have used S&amp;P&#xae; ratings. All ratings are as of the date indicated and do not reflect subsequent changes.




&#160;

TOP STATES
(% of Fund's net assets)


Illinois

13.2


New York

8.1


Texas

7.4


New Jersey

6.5


Pennsylvania

6.1


&#160;

&#160;




&#160;
</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000048850_RS_0_Member"
      decimals="INF"
      id="ixv-143778"
      unitRef="pure">0.230</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000048850_RS_1_Member"
      decimals="INF"
      id="ixv-143779"
      unitRef="pure">0.224</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000048850_RS_2_Member"
      decimals="INF"
      id="ixv-143780"
      unitRef="pure">0.150</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000048850_RS_3_Member"
      decimals="INF"
      id="ixv-143781"
      unitRef="pure">0.096</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000048850_RS_4_Member"
      decimals="INF"
      id="ixv-143782"
      unitRef="pure">0.089</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000048850_RS_5_Member"
      decimals="INF"
      id="ixv-143783"
      unitRef="pure">0.070</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000048850_RS_6_Member"
      decimals="INF"
      id="ixv-143784"
      unitRef="pure">0.060</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000048850_RS_7_Member"
      decimals="INF"
      id="ixv-143785"
      unitRef="pure">0.081</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000048850_QD_AAA_Member"
      decimals="INF"
      id="ixv-143786"
      unitRef="pure">0.056</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000048850_QD_AA_Member"
      decimals="INF"
      id="ixv-143787"
      unitRef="pure">0.305</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000048850_QD_A_Member"
      decimals="INF"
      id="ixv-143788"
      unitRef="pure">0.474</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000048850_QD_BBB_Member"
      decimals="INF"
      id="ixv-143789"
      unitRef="pure">0.092</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000048850_QD_BB_Member"
      decimals="INF"
      id="ixv-143790"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000048850_QD_B_Member"
      decimals="INF"
      id="ixv-143791"
      unitRef="pure">0.005</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000048850_QD_CCCCCC_Member"
      decimals="INF"
      id="ixv-143792"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000048850_QD_NotRated_Member"
      decimals="INF"
      id="ixv-143793"
      unitRef="pure">0.044</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000048850_QD_ShortTermInvestmentsandNetOtherAssetsLiabilities_Member"
      decimals="INF"
      id="ixv-143794"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000048850_TS_0_Member"
      decimals="INF"
      id="ixv-143795"
      unitRef="pure">0.132</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000048850_TS_1_Member"
      decimals="INF"
      id="ixv-143796"
      unitRef="pure">0.081</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000048850_TS_2_Member"
      decimals="INF"
      id="ixv-143797"
      unitRef="pure">0.074</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000048850_TS_3_Member"
      decimals="INF"
      id="ixv-143798"
      unitRef="pure">0.065</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000048850_TS_4_Member"
      decimals="INF"
      id="ixv-143799"
      unitRef="pure">0.061</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-1542">2024-07-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000235228_ClassMember" id="ixv-1554">Fidelity&#xae; Sustainable Intermediate Municipal Income Fund</oef:FundName>
    <oef:ClassName contextRef="C000235228_ClassMember" id="ixv-1557">Fidelity Advisor&#xae; Sustainable Intermediate Municipal Income Fund Class A</oef:ClassName>
    <dei:TradingSymbol contextRef="C000235228_ClassMember" id="ixv-1561">FASJX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000235228_ClassMember" id="ixv-1581">This semi-annual shareholder report contains information about Fidelity&#xae; Sustainable Intermediate Municipal Income Fund for the period February 1, 2024 to July 31, 2024.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000235228_ClassMember" id="ixv-1583">semi-annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000235228_ClassMember" id="ixv-1588">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-877-208-0098 or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000235228_ClassMember" id="ixv-1590">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000235228_ClassMember" id="ixv-1593">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000235228_ClassMember" id="ixv-1596">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000235228_ClassMember" id="ixv-1603">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What were your Fund costs for the last six months?&lt;/span&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(based on hypothetical $10,000 investment)&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:43%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:25%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs of a $10,000 investment&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:31%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs paid as a percentage of a $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:43%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class A&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:25%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;31&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:31%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;0.62&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000235228_ClassMember"
      decimals="0"
      id="ixv-143800"
      unitRef="usd">31</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000235228_ClassMember"
      decimals="INF"
      id="ixv-143801"
      unitRef="pure">0.0062</oef:ExpenseRatioPct>
    <oef:AddlFundStatisticsTextBlock contextRef="C000235228_ClassMember" id="ixv-1644">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;span style="line-height:16px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of July 31, 2024)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;15,835,114&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;249&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Portfolio Turnover&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;15&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
    <us-gaap:AssetsNet
      contextRef="C000235228_InstantMember"
      decimals="0"
      id="ixv-143802"
      unitRef="usd">15835114</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000235228_InstantMember"
      decimals="INF"
      id="ixv-143803"
      unitRef="holding">249</oef:HoldingsCount>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000235228_ClassMember"
      decimals="INF"
      id="ixv-143804"
      unitRef="pure">0.15</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000235228_ClassMember" id="ixv-1707">
&#160;

REVENUE SOURCES
 (% of Fund's net assets)


Health Care

21.2

&#160;


General Obligations

21.1

&#160;


Education

16.3

&#160;


Electric Utilities

9.6

&#160;


Housing

8.1

&#160;


State G.O.

6.7

&#160;


Special Tax

5.6

&#160;


Others(Individually Less Than 5%)

11.4

&#160;


100.0

&#160;


&#160;




&#160;

AAA

8.9


AA

41.8


A

32.1


BBB

17.0


BB

0.3


Not Rated

0.1




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;


Short-Term Investments and Net Other Assets (Liabilities) - (0.2)%*


&#160;


We have used ratings from Moody's Investors Service, Inc. Where Moody's&#xae; ratings are not available, we have used S&amp;P&#xae; ratings. All ratings are as of the date indicated and do not reflect subsequent changes.




&#160;

TOP STATES
(% of Fund's net assets)


New York

9.1


Illinois

8.3


California

7.0


Florida

5.7


Georgia

5.6


&#160;

&#160;




&#160;
</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000235228_RS_0_Member"
      decimals="INF"
      id="ixv-143805"
      unitRef="pure">0.212</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235228_RS_1_Member"
      decimals="INF"
      id="ixv-143806"
      unitRef="pure">0.211</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235228_RS_2_Member"
      decimals="INF"
      id="ixv-143807"
      unitRef="pure">0.163</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235228_RS_3_Member"
      decimals="INF"
      id="ixv-143808"
      unitRef="pure">0.096</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235228_RS_4_Member"
      decimals="INF"
      id="ixv-143809"
      unitRef="pure">0.081</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235228_RS_5_Member"
      decimals="INF"
      id="ixv-143810"
      unitRef="pure">0.067</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235228_RS_6_Member"
      decimals="INF"
      id="ixv-143811"
      unitRef="pure">0.056</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235228_RS_7_Member"
      decimals="INF"
      id="ixv-143812"
      unitRef="pure">0.114</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235228_QD_AAA_Member"
      decimals="INF"
      id="ixv-143813"
      unitRef="pure">0.089</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235228_QD_AA_Member"
      decimals="INF"
      id="ixv-143814"
      unitRef="pure">0.418</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235228_QD_A_Member"
      decimals="INF"
      id="ixv-143815"
      unitRef="pure">0.321</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235228_QD_BBB_Member"
      decimals="INF"
      id="ixv-143816"
      unitRef="pure">0.170</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235228_QD_BB_Member"
      decimals="INF"
      id="ixv-143817"
      unitRef="pure">0.003</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235228_QD_NotRated_Member"
      decimals="INF"
      id="ixv-143818"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235228_TS_0_Member"
      decimals="INF"
      id="ixv-143819"
      unitRef="pure">0.091</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235228_TS_1_Member"
      decimals="INF"
      id="ixv-143820"
      unitRef="pure">0.083</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235228_TS_2_Member"
      decimals="INF"
      id="ixv-143821"
      unitRef="pure">0.070</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235228_TS_3_Member"
      decimals="INF"
      id="ixv-143822"
      unitRef="pure">0.057</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235228_TS_4_Member"
      decimals="INF"
      id="ixv-143823"
      unitRef="pure">0.056</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-1970">2024-07-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000235225_ClassMember" id="ixv-1982">Fidelity&#xae; Sustainable Intermediate Municipal Income Fund</oef:FundName>
    <oef:ClassName contextRef="C000235225_ClassMember" id="ixv-1985">Fidelity Advisor&#xae; Sustainable Intermediate Municipal Income Fund Class C</oef:ClassName>
    <dei:TradingSymbol contextRef="C000235225_ClassMember" id="ixv-1989">FASNX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000235225_ClassMember" id="ixv-2009">This semi-annual shareholder report contains information about Fidelity&#xae; Sustainable Intermediate Municipal Income Fund for the period February 1, 2024 to July 31, 2024.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000235225_ClassMember" id="ixv-2011">semi-annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000235225_ClassMember" id="ixv-2016">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-877-208-0098 or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000235225_ClassMember" id="ixv-2018">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000235225_ClassMember" id="ixv-2021">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000235225_ClassMember" id="ixv-2024">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000235225_ClassMember" id="ixv-2031">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What were your Fund costs for the last six months?&lt;/span&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(based on hypothetical $10,000 investment)&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:43%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:25%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs of a $10,000 investment&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:31%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs paid as a percentage of a $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:43%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class C&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:25%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;68&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:31%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;1.37&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000235225_ClassMember"
      decimals="0"
      id="ixv-143824"
      unitRef="usd">68</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000235225_ClassMember"
      decimals="INF"
      id="ixv-143825"
      unitRef="pure">0.0137</oef:ExpenseRatioPct>
    <oef:AddlFundStatisticsTextBlock contextRef="C000235225_ClassMember" id="ixv-2072">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;span style="line-height:16px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of July 31, 2024)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;15,835,114&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;249&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Portfolio Turnover&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;15&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
    <us-gaap:AssetsNet
      contextRef="C000235225_InstantMember"
      decimals="0"
      id="ixv-143826"
      unitRef="usd">15835114</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000235225_InstantMember"
      decimals="INF"
      id="ixv-143827"
      unitRef="holding">249</oef:HoldingsCount>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000235225_ClassMember"
      decimals="INF"
      id="ixv-143828"
      unitRef="pure">0.15</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000235225_ClassMember" id="ixv-2135">
&#160;

REVENUE SOURCES
 (% of Fund's net assets)


Health Care

21.2

&#160;


General Obligations

21.1

&#160;


Education

16.3

&#160;


Electric Utilities

9.6

&#160;


Housing

8.1

&#160;


State G.O.

6.7

&#160;


Special Tax

5.6

&#160;


Others(Individually Less Than 5%)

11.4

&#160;


100.0

&#160;


&#160;




&#160;

AAA

8.9


AA

41.8


A

32.1


BBB

17.0


BB

0.3


Not Rated

0.1




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;


Short-Term Investments and Net Other Assets (Liabilities) - (0.2)%*


&#160;


We have used ratings from Moody's Investors Service, Inc. Where Moody's&#xae; ratings are not available, we have used S&amp;P&#xae; ratings. All ratings are as of the date indicated and do not reflect subsequent changes.




&#160;

TOP STATES
(% of Fund's net assets)


New York

9.1


Illinois

8.3


California

7.0


Florida

5.7


Georgia

5.6


&#160;

&#160;




&#160;
</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000235225_RS_0_Member"
      decimals="INF"
      id="ixv-143829"
      unitRef="pure">0.212</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235225_RS_1_Member"
      decimals="INF"
      id="ixv-143830"
      unitRef="pure">0.211</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235225_RS_2_Member"
      decimals="INF"
      id="ixv-143831"
      unitRef="pure">0.163</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235225_RS_3_Member"
      decimals="INF"
      id="ixv-143832"
      unitRef="pure">0.096</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235225_RS_4_Member"
      decimals="INF"
      id="ixv-143833"
      unitRef="pure">0.081</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235225_RS_5_Member"
      decimals="INF"
      id="ixv-143834"
      unitRef="pure">0.067</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235225_RS_6_Member"
      decimals="INF"
      id="ixv-143835"
      unitRef="pure">0.056</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235225_RS_7_Member"
      decimals="INF"
      id="ixv-143836"
      unitRef="pure">0.114</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235225_QD_AAA_Member"
      decimals="INF"
      id="ixv-143837"
      unitRef="pure">0.089</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235225_QD_AA_Member"
      decimals="INF"
      id="ixv-143838"
      unitRef="pure">0.418</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235225_QD_A_Member"
      decimals="INF"
      id="ixv-143839"
      unitRef="pure">0.321</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235225_QD_BBB_Member"
      decimals="INF"
      id="ixv-143840"
      unitRef="pure">0.170</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235225_QD_BB_Member"
      decimals="INF"
      id="ixv-143841"
      unitRef="pure">0.003</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235225_QD_NotRated_Member"
      decimals="INF"
      id="ixv-143842"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235225_TS_0_Member"
      decimals="INF"
      id="ixv-143843"
      unitRef="pure">0.091</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235225_TS_1_Member"
      decimals="INF"
      id="ixv-143844"
      unitRef="pure">0.083</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235225_TS_2_Member"
      decimals="INF"
      id="ixv-143845"
      unitRef="pure">0.070</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235225_TS_3_Member"
      decimals="INF"
      id="ixv-143846"
      unitRef="pure">0.057</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235225_TS_4_Member"
      decimals="INF"
      id="ixv-143847"
      unitRef="pure">0.056</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-2398">2024-07-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000240981_ClassMember" id="ixv-2410">Fidelity&#xae; Municipal Core Plus Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000240981_ClassMember" id="ixv-2413">Fidelity Advisor&#xae; Municipal Core Plus Bond Fund Class A</oef:ClassName>
    <dei:TradingSymbol contextRef="C000240981_ClassMember" id="ixv-2417">FMBMX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000240981_ClassMember" id="ixv-2437">This semi-annual shareholder report contains information about Fidelity&#xae; Municipal Core Plus Bond Fund for the period February 1, 2024 to July 31, 2024.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000240981_ClassMember" id="ixv-2439">semi-annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000240981_ClassMember" id="ixv-2444">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-877-208-0098 or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000240981_ClassMember" id="ixv-2446">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000240981_ClassMember" id="ixv-2449">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000240981_ClassMember" id="ixv-2452">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000240981_ClassMember" id="ixv-2459">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What were your Fund costs for the last six months?&lt;/span&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(based on hypothetical $10,000 investment)&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:43%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:25%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs of a $10,000 investment&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:31%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs paid as a percentage of a $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:43%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class A&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:25%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;31&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:31%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;0.62&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000240981_ClassMember"
      decimals="0"
      id="ixv-143848"
      unitRef="usd">31</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000240981_ClassMember"
      decimals="INF"
      id="ixv-143849"
      unitRef="pure">0.0062</oef:ExpenseRatioPct>
    <oef:AddlFundStatisticsTextBlock contextRef="C000240981_ClassMember" id="ixv-2500">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;span style="line-height:16px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of July 31, 2024)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;59,223,606&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;315&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Portfolio Turnover&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;30&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
    <us-gaap:AssetsNet
      contextRef="C000240981_InstantMember"
      decimals="0"
      id="ixv-143850"
      unitRef="usd">59223606</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000240981_InstantMember"
      decimals="INF"
      id="ixv-143851"
      unitRef="holding">315</oef:HoldingsCount>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000240981_ClassMember"
      decimals="INF"
      id="ixv-143852"
      unitRef="pure">0.30</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000240981_ClassMember" id="ixv-2563">
&#160;

REVENUE SOURCES
 (% of Fund's net assets)


Health Care

19.7

&#160;


General Obligations

16.9

&#160;


Transportation

12.2

&#160;


Education

11.3

&#160;


Housing

7.4

&#160;


State G.O.

7.0

&#160;


Special Tax

6.5

&#160;


Others(Individually Less Than 5%)

19.0

&#160;


100.0

&#160;


&#160;




&#160;

AAA

8.1


AA

30.2


A

30.9


BBB

20.6


BB

0.6


B

0.5


Not Rated

5.4


Short-Term Investments and Net Other Assets (Liabilities)

3.7




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;


&#160;


We have used ratings from Moody's Investors Service, Inc. Where Moody's&#xae; ratings are not available, we have used S&amp;P&#xae; ratings. All ratings are as of the date indicated and do not reflect subsequent changes.




&#160;

TOP STATES
(% of Fund's net assets)


Illinois

10.4


New Jersey

8.6


Florida

6.1


Alabama

5.4


Connecticut

5.3


&#160;

&#160;




&#160;
</oef:HoldingsTableTextBlock>
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      unitRef="pure">0.197</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240981_RS_1_Member"
      decimals="INF"
      id="ixv-143854"
      unitRef="pure">0.169</oef:PctOfNav>
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      decimals="INF"
      id="ixv-143855"
      unitRef="pure">0.122</oef:PctOfNav>
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      contextRef="C000240981_RS_3_Member"
      decimals="INF"
      id="ixv-143856"
      unitRef="pure">0.113</oef:PctOfNav>
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      unitRef="pure">0.074</oef:PctOfNav>
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      decimals="INF"
      id="ixv-143858"
      unitRef="pure">0.070</oef:PctOfNav>
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      unitRef="pure">0.065</oef:PctOfNav>
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      id="ixv-143860"
      unitRef="pure">0.190</oef:PctOfNav>
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      unitRef="pure">0.081</oef:PctOfNav>
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      id="ixv-143862"
      unitRef="pure">0.302</oef:PctOfNav>
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      contextRef="C000240981_QD_A_Member"
      decimals="INF"
      id="ixv-143863"
      unitRef="pure">0.309</oef:PctOfNav>
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      contextRef="C000240981_QD_BBB_Member"
      decimals="INF"
      id="ixv-143864"
      unitRef="pure">0.206</oef:PctOfNav>
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      contextRef="C000240981_QD_BB_Member"
      decimals="INF"
      id="ixv-143865"
      unitRef="pure">0.006</oef:PctOfNav>
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      decimals="INF"
      id="ixv-143866"
      unitRef="pure">0.005</oef:PctOfNav>
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      decimals="INF"
      id="ixv-143867"
      unitRef="pure">0.054</oef:PctOfNav>
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      contextRef="C000240981_QD_ShortTermInvestmentsandNetOtherAssetsLiabilities_Member"
      decimals="INF"
      id="ixv-143868"
      unitRef="pure">0.037</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240981_TS_0_Member"
      decimals="INF"
      id="ixv-143869"
      unitRef="pure">0.104</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240981_TS_1_Member"
      decimals="INF"
      id="ixv-143870"
      unitRef="pure">0.086</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240981_TS_2_Member"
      decimals="INF"
      id="ixv-143871"
      unitRef="pure">0.061</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240981_TS_3_Member"
      decimals="INF"
      id="ixv-143872"
      unitRef="pure">0.054</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240981_TS_4_Member"
      decimals="INF"
      id="ixv-143873"
      unitRef="pure">0.053</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-2834">2024-07-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000240980_ClassMember" id="ixv-2846">Fidelity&#xae; Municipal Core Plus Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000240980_ClassMember" id="ixv-2849">Fidelity Advisor&#xae; Municipal Core Plus Bond Fund Class M</oef:ClassName>
    <dei:TradingSymbol contextRef="C000240980_ClassMember" id="ixv-2853">FMBFX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000240980_ClassMember" id="ixv-2873">This semi-annual shareholder report contains information about Fidelity&#xae; Municipal Core Plus Bond Fund for the period February 1, 2024 to July 31, 2024.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000240980_ClassMember" id="ixv-2875">semi-annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000240980_ClassMember" id="ixv-2880">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-877-208-0098 or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000240980_ClassMember" id="ixv-2882">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000240980_ClassMember" id="ixv-2885">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000240980_ClassMember" id="ixv-2888">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000240980_ClassMember" id="ixv-2895">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What were your Fund costs for the last six months?&lt;/span&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(based on hypothetical $10,000 investment)&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:43%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:25%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs of a $10,000 investment&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:31%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs paid as a percentage of a $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:43%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class M&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:25%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;31&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:31%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;0.62&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000240980_ClassMember"
      decimals="0"
      id="ixv-143874"
      unitRef="usd">31</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000240980_ClassMember"
      decimals="INF"
      id="ixv-143875"
      unitRef="pure">0.0062</oef:ExpenseRatioPct>
    <oef:AddlFundStatisticsTextBlock contextRef="C000240980_ClassMember" id="ixv-2936">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;span style="line-height:16px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of July 31, 2024)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;59,223,606&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;315&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Portfolio Turnover&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;30&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
    <us-gaap:AssetsNet
      contextRef="C000240980_InstantMember"
      decimals="0"
      id="ixv-143876"
      unitRef="usd">59223606</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000240980_InstantMember"
      decimals="INF"
      id="ixv-143877"
      unitRef="holding">315</oef:HoldingsCount>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000240980_ClassMember"
      decimals="INF"
      id="ixv-143878"
      unitRef="pure">0.30</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000240980_ClassMember" id="ixv-2999">
&#160;

REVENUE SOURCES
 (% of Fund's net assets)


Health Care

19.7

&#160;


General Obligations

16.9

&#160;


Transportation

12.2

&#160;


Education

11.3

&#160;


Housing

7.4

&#160;


State G.O.

7.0

&#160;


Special Tax

6.5

&#160;


Others(Individually Less Than 5%)

19.0

&#160;


100.0

&#160;


&#160;




&#160;

AAA

8.1


AA

30.2


A

30.9


BBB

20.6


BB

0.6


B

0.5


Not Rated

5.4


Short-Term Investments and Net Other Assets (Liabilities)

3.7




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;


&#160;


We have used ratings from Moody's Investors Service, Inc. Where Moody's&#xae; ratings are not available, we have used S&amp;P&#xae; ratings. All ratings are as of the date indicated and do not reflect subsequent changes.




&#160;

TOP STATES
(% of Fund's net assets)


Illinois

10.4


New Jersey

8.6


Florida

6.1


Alabama

5.4


Connecticut

5.3


&#160;

&#160;




&#160;
</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000240980_RS_0_Member"
      decimals="INF"
      id="ixv-143879"
      unitRef="pure">0.197</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240980_RS_1_Member"
      decimals="INF"
      id="ixv-143880"
      unitRef="pure">0.169</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240980_RS_2_Member"
      decimals="INF"
      id="ixv-143881"
      unitRef="pure">0.122</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240980_RS_3_Member"
      decimals="INF"
      id="ixv-143882"
      unitRef="pure">0.113</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240980_RS_4_Member"
      decimals="INF"
      id="ixv-143883"
      unitRef="pure">0.074</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240980_RS_5_Member"
      decimals="INF"
      id="ixv-143884"
      unitRef="pure">0.070</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-143885"
      unitRef="pure">0.065</oef:PctOfNav>
    <oef:PctOfNav
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      id="ixv-143886"
      unitRef="pure">0.190</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-143887"
      unitRef="pure">0.081</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240980_QD_AA_Member"
      decimals="INF"
      id="ixv-143888"
      unitRef="pure">0.302</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240980_QD_A_Member"
      decimals="INF"
      id="ixv-143889"
      unitRef="pure">0.309</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240980_QD_BBB_Member"
      decimals="INF"
      id="ixv-143890"
      unitRef="pure">0.206</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240980_QD_BB_Member"
      decimals="INF"
      id="ixv-143891"
      unitRef="pure">0.006</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240980_QD_B_Member"
      decimals="INF"
      id="ixv-143892"
      unitRef="pure">0.005</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240980_QD_NotRated_Member"
      decimals="INF"
      id="ixv-143893"
      unitRef="pure">0.054</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240980_QD_ShortTermInvestmentsandNetOtherAssetsLiabilities_Member"
      decimals="INF"
      id="ixv-143894"
      unitRef="pure">0.037</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240980_TS_0_Member"
      decimals="INF"
      id="ixv-143895"
      unitRef="pure">0.104</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240980_TS_1_Member"
      decimals="INF"
      id="ixv-143896"
      unitRef="pure">0.086</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240980_TS_2_Member"
      decimals="INF"
      id="ixv-143897"
      unitRef="pure">0.061</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240980_TS_3_Member"
      decimals="INF"
      id="ixv-143898"
      unitRef="pure">0.054</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240980_TS_4_Member"
      decimals="INF"
      id="ixv-143899"
      unitRef="pure">0.053</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-3270">2024-07-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000200825_ClassMember" id="ixv-3282">Fidelity&#xae; SAI Tax-Free Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000200825_ClassMember" id="ixv-3285">Fidelity&#xae; SAI Tax-Free Bond Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000200825_ClassMember" id="ixv-3289">FSAJX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000200825_ClassMember" id="ixv-3309">This semi-annual shareholder report contains information about Fidelity&#xae; SAI Tax-Free Bond Fund for the period February 1, 2024 to July 31, 2024.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000200825_ClassMember" id="ixv-3311">semi-annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000200825_ClassMember" id="ixv-3316">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-800-544-3455 or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000200825_ClassMember" id="ixv-3318">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000200825_ClassMember" id="ixv-3321">1-800-544-3455</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000200825_ClassMember" id="ixv-3324">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000200825_ClassMember" id="ixv-3331">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What were your Fund costs for the last six months?&lt;/span&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(based on hypothetical $10,000 investment)&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:43%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:25%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs of a $10,000 investment&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:31%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs paid as a percentage of a $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:43%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; SAI Tax-Free Bond Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:25%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;12&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:31%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;0.25&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000200825_ClassMember"
      decimals="0"
      id="ixv-143900"
      unitRef="usd">12</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000200825_ClassMember"
      decimals="INF"
      id="ixv-143901"
      unitRef="pure">0.0025</oef:ExpenseRatioPct>
    <oef:AddlFundStatisticsTextBlock contextRef="C000200825_ClassMember" id="ixv-3372">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;span style="line-height:16px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of July 31, 2024)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;2,692,523,796&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;1,279&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Portfolio Turnover&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;7&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
    <us-gaap:AssetsNet
      contextRef="C000200825_InstantMember"
      decimals="0"
      id="ixv-143902"
      unitRef="usd">2692523796</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000200825_InstantMember"
      decimals="INF"
      id="ixv-143903"
      unitRef="holding">1279</oef:HoldingsCount>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000200825_ClassMember"
      decimals="INF"
      id="ixv-143904"
      unitRef="pure">0.07</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000200825_ClassMember" id="ixv-3435">
&#160;

REVENUE SOURCES
 (% of Fund's net assets)


General Obligations

20.3

&#160;


Health Care

19.6

&#160;


Special Tax

12.9

&#160;


Transportation

10.8

&#160;


Education

10.3

&#160;


Housing

9.0

&#160;


State G.O.

6.7

&#160;


Others(Individually Less Than 5%)

10.4

&#160;


100.0

&#160;


&#160;




&#160;

AAA

7.5


AA

35.7


A

40.4


BBB

9.5


BB

0.6


B

0.4


CCC,CC,C

0.1


Not Rated

3.6


Short-Term Investments and Net Other Assets (Liabilities)

2.2




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;


&#160;


We have used ratings from Moody's Investors Service, Inc. Where Moody's&#xae; ratings are not available, we have used S&amp;P&#xae; ratings. All ratings are as of the date indicated and do not reflect subsequent changes.




&#160;

TOP STATES
(% of Fund's net assets)


New York

14.3


Illinois

13.3


Texas

8.5


New Jersey

5.9


Pennsylvania

4.7


&#160;

&#160;




&#160;
</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000200825_RS_0_Member"
      decimals="INF"
      id="ixv-143905"
      unitRef="pure">0.203</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000200825_RS_1_Member"
      decimals="INF"
      id="ixv-143906"
      unitRef="pure">0.196</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000200825_RS_2_Member"
      decimals="INF"
      id="ixv-143907"
      unitRef="pure">0.129</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000200825_RS_3_Member"
      decimals="INF"
      id="ixv-143908"
      unitRef="pure">0.108</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000200825_RS_4_Member"
      decimals="INF"
      id="ixv-143909"
      unitRef="pure">0.103</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000200825_RS_5_Member"
      decimals="INF"
      id="ixv-143910"
      unitRef="pure">0.090</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000200825_RS_6_Member"
      decimals="INF"
      id="ixv-143911"
      unitRef="pure">0.067</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000200825_RS_7_Member"
      decimals="INF"
      id="ixv-143912"
      unitRef="pure">0.104</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000200825_QD_AAA_Member"
      decimals="INF"
      id="ixv-143913"
      unitRef="pure">0.075</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000200825_QD_AA_Member"
      decimals="INF"
      id="ixv-143914"
      unitRef="pure">0.357</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000200825_QD_A_Member"
      decimals="INF"
      id="ixv-143915"
      unitRef="pure">0.404</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000200825_QD_BBB_Member"
      decimals="INF"
      id="ixv-143916"
      unitRef="pure">0.095</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000200825_QD_BB_Member"
      decimals="INF"
      id="ixv-143917"
      unitRef="pure">0.006</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000200825_QD_B_Member"
      decimals="INF"
      id="ixv-143918"
      unitRef="pure">0.004</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000200825_QD_CCCCCC_Member"
      decimals="INF"
      id="ixv-143919"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000200825_QD_NotRated_Member"
      decimals="INF"
      id="ixv-143920"
      unitRef="pure">0.036</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000200825_QD_ShortTermInvestmentsandNetOtherAssetsLiabilities_Member"
      decimals="INF"
      id="ixv-143921"
      unitRef="pure">0.022</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000200825_TS_0_Member"
      decimals="INF"
      id="ixv-143922"
      unitRef="pure">0.143</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000200825_TS_1_Member"
      decimals="INF"
      id="ixv-143923"
      unitRef="pure">0.133</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000200825_TS_2_Member"
      decimals="INF"
      id="ixv-143924"
      unitRef="pure">0.085</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000200825_TS_3_Member"
      decimals="INF"
      id="ixv-143925"
      unitRef="pure">0.059</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000200825_TS_4_Member"
      decimals="INF"
      id="ixv-143926"
      unitRef="pure">0.047</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-3712">2024-07-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000235223_ClassMember" id="ixv-3724">Fidelity&#xae; Sustainable Intermediate Municipal Income Fund</oef:FundName>
    <oef:ClassName contextRef="C000235223_ClassMember" id="ixv-3727">Fidelity&#xae; Sustainable Intermediate Municipal Income Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000235223_ClassMember" id="ixv-3731">FSIKX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000235223_ClassMember" id="ixv-3751">This semi-annual shareholder report contains information about Fidelity&#xae; Sustainable Intermediate Municipal Income Fund for the period February 1, 2024 to July 31, 2024.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000235223_ClassMember" id="ixv-3753">semi-annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000235223_ClassMember" id="ixv-3758">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-800-544-8544 or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000235223_ClassMember" id="ixv-3760">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000235223_ClassMember" id="ixv-3763">1-800-544-8544</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000235223_ClassMember" id="ixv-3766">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000235223_ClassMember" id="ixv-3773">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What were your Fund costs for the last six months?&lt;/span&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(based on hypothetical $10,000 investment)&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:43%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:25%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs of a $10,000 investment&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:31%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs paid as a percentage of a $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:43%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Sustainable Intermediate Municipal Income Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:25%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;18&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:31%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;0.37&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
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      decimals="0"
      id="ixv-143927"
      unitRef="usd">18</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000235223_ClassMember"
      decimals="INF"
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      unitRef="pure">0.0037</oef:ExpenseRatioPct>
    <oef:AddlFundStatisticsTextBlock contextRef="C000235223_ClassMember" id="ixv-3814">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;span style="line-height:16px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of July 31, 2024)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;15,835,114&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;249&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Portfolio Turnover&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;15&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
    <us-gaap:AssetsNet
      contextRef="C000235223_InstantMember"
      decimals="0"
      id="ixv-143929"
      unitRef="usd">15835114</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000235223_InstantMember"
      decimals="INF"
      id="ixv-143930"
      unitRef="holding">249</oef:HoldingsCount>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000235223_ClassMember"
      decimals="INF"
      id="ixv-143931"
      unitRef="pure">0.15</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000235223_ClassMember" id="ixv-3877">
&#160;

REVENUE SOURCES
 (% of Fund's net assets)


Health Care

21.2

&#160;


General Obligations

21.1

&#160;


Education

16.3

&#160;


Electric Utilities

9.6

&#160;


Housing

8.1

&#160;


State G.O.

6.7

&#160;


Special Tax

5.6

&#160;


Others(Individually Less Than 5%)

11.4

&#160;


100.0

&#160;


&#160;




&#160;

AAA

8.9


AA

41.8


A

32.1


BBB

17.0


BB

0.3


Not Rated

0.1




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;


Short-Term Investments and Net Other Assets (Liabilities) - (0.2)%*


&#160;


We have used ratings from Moody's Investors Service, Inc. Where Moody's&#xae; ratings are not available, we have used S&amp;P&#xae; ratings. All ratings are as of the date indicated and do not reflect subsequent changes.




&#160;

TOP STATES
(% of Fund's net assets)


New York

9.1


Illinois

8.3


California

7.0


Florida

5.7


Georgia

5.6


&#160;

&#160;




&#160;
</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
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    <oef:PctOfNav
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      decimals="INF"
      id="ixv-143933"
      unitRef="pure">0.211</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235223_RS_2_Member"
      decimals="INF"
      id="ixv-143934"
      unitRef="pure">0.163</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235223_RS_3_Member"
      decimals="INF"
      id="ixv-143935"
      unitRef="pure">0.096</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235223_RS_4_Member"
      decimals="INF"
      id="ixv-143936"
      unitRef="pure">0.081</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235223_RS_5_Member"
      decimals="INF"
      id="ixv-143937"
      unitRef="pure">0.067</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235223_RS_6_Member"
      decimals="INF"
      id="ixv-143938"
      unitRef="pure">0.056</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235223_RS_7_Member"
      decimals="INF"
      id="ixv-143939"
      unitRef="pure">0.114</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235223_QD_AAA_Member"
      decimals="INF"
      id="ixv-143940"
      unitRef="pure">0.089</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235223_QD_AA_Member"
      decimals="INF"
      id="ixv-143941"
      unitRef="pure">0.418</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-143942"
      unitRef="pure">0.321</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235223_QD_BBB_Member"
      decimals="INF"
      id="ixv-143943"
      unitRef="pure">0.170</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235223_QD_BB_Member"
      decimals="INF"
      id="ixv-143944"
      unitRef="pure">0.003</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235223_QD_NotRated_Member"
      decimals="INF"
      id="ixv-143945"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235223_TS_0_Member"
      decimals="INF"
      id="ixv-143946"
      unitRef="pure">0.091</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235223_TS_1_Member"
      decimals="INF"
      id="ixv-143947"
      unitRef="pure">0.083</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235223_TS_2_Member"
      decimals="INF"
      id="ixv-143948"
      unitRef="pure">0.070</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235223_TS_3_Member"
      decimals="INF"
      id="ixv-143949"
      unitRef="pure">0.057</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235223_TS_4_Member"
      decimals="INF"
      id="ixv-143950"
      unitRef="pure">0.056</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-4140">2024-07-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000235224_ClassMember" id="ixv-4152">Fidelity&#xae; Sustainable Intermediate Municipal Income Fund</oef:FundName>
    <oef:ClassName contextRef="C000235224_ClassMember" id="ixv-4155">Fidelity Advisor&#xae; Sustainable Intermediate Municipal Income Fund Class M</oef:ClassName>
    <dei:TradingSymbol contextRef="C000235224_ClassMember" id="ixv-4159">FASLX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000235224_ClassMember" id="ixv-4179">This semi-annual shareholder report contains information about Fidelity&#xae; Sustainable Intermediate Municipal Income Fund for the period February 1, 2024 to July 31, 2024.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000235224_ClassMember" id="ixv-4181">semi-annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000235224_ClassMember" id="ixv-4186">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-877-208-0098 or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000235224_ClassMember" id="ixv-4188">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000235224_ClassMember" id="ixv-4191">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000235224_ClassMember" id="ixv-4194">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000235224_ClassMember" id="ixv-4201">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What were your Fund costs for the last six months?&lt;/span&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(based on hypothetical $10,000 investment)&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:43%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:25%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs of a $10,000 investment&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:31%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs paid as a percentage of a $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:43%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class M&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:25%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;31&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:31%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;0.62&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000235224_ClassMember"
      decimals="0"
      id="ixv-143951"
      unitRef="usd">31</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000235224_ClassMember"
      decimals="INF"
      id="ixv-143952"
      unitRef="pure">0.0062</oef:ExpenseRatioPct>
    <oef:AddlFundStatisticsTextBlock contextRef="C000235224_ClassMember" id="ixv-4242">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;span style="line-height:16px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of July 31, 2024)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;15,835,114&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;249&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Portfolio Turnover&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;15&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
    <us-gaap:AssetsNet
      contextRef="C000235224_InstantMember"
      decimals="0"
      id="ixv-143953"
      unitRef="usd">15835114</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000235224_InstantMember"
      decimals="INF"
      id="ixv-143954"
      unitRef="holding">249</oef:HoldingsCount>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000235224_ClassMember"
      decimals="INF"
      id="ixv-143955"
      unitRef="pure">0.15</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000235224_ClassMember" id="ixv-4305">
&#160;

REVENUE SOURCES
 (% of Fund's net assets)


Health Care

21.2

&#160;


General Obligations

21.1

&#160;


Education

16.3

&#160;


Electric Utilities

9.6

&#160;


Housing

8.1

&#160;


State G.O.

6.7

&#160;


Special Tax

5.6

&#160;


Others(Individually Less Than 5%)

11.4

&#160;


100.0

&#160;


&#160;




&#160;

AAA

8.9


AA

41.8


A

32.1


BBB

17.0


BB

0.3


Not Rated

0.1




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;


Short-Term Investments and Net Other Assets (Liabilities) - (0.2)%*


&#160;


We have used ratings from Moody's Investors Service, Inc. Where Moody's&#xae; ratings are not available, we have used S&amp;P&#xae; ratings. All ratings are as of the date indicated and do not reflect subsequent changes.




&#160;

TOP STATES
(% of Fund's net assets)


New York

9.1


Illinois

8.3


California

7.0


Florida

5.7


Georgia

5.6


&#160;

&#160;




&#160;
</oef:HoldingsTableTextBlock>
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      contextRef="C000235224_RS_0_Member"
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      id="ixv-143956"
      unitRef="pure">0.212</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235224_RS_1_Member"
      decimals="INF"
      id="ixv-143957"
      unitRef="pure">0.211</oef:PctOfNav>
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      contextRef="C000235224_RS_2_Member"
      decimals="INF"
      id="ixv-143958"
      unitRef="pure">0.163</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235224_RS_3_Member"
      decimals="INF"
      id="ixv-143959"
      unitRef="pure">0.096</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235224_RS_4_Member"
      decimals="INF"
      id="ixv-143960"
      unitRef="pure">0.081</oef:PctOfNav>
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      contextRef="C000235224_RS_5_Member"
      decimals="INF"
      id="ixv-143961"
      unitRef="pure">0.067</oef:PctOfNav>
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      id="ixv-143962"
      unitRef="pure">0.056</oef:PctOfNav>
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      decimals="INF"
      id="ixv-143963"
      unitRef="pure">0.114</oef:PctOfNav>
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      id="ixv-143964"
      unitRef="pure">0.089</oef:PctOfNav>
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      contextRef="C000235224_QD_AA_Member"
      decimals="INF"
      id="ixv-143965"
      unitRef="pure">0.418</oef:PctOfNav>
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      contextRef="C000235224_QD_A_Member"
      decimals="INF"
      id="ixv-143966"
      unitRef="pure">0.321</oef:PctOfNav>
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      contextRef="C000235224_QD_BBB_Member"
      decimals="INF"
      id="ixv-143967"
      unitRef="pure">0.170</oef:PctOfNav>
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      contextRef="C000235224_QD_BB_Member"
      decimals="INF"
      id="ixv-143968"
      unitRef="pure">0.003</oef:PctOfNav>
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      contextRef="C000235224_QD_NotRated_Member"
      decimals="INF"
      id="ixv-143969"
      unitRef="pure">0.001</oef:PctOfNav>
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      contextRef="C000235224_TS_0_Member"
      decimals="INF"
      id="ixv-143970"
      unitRef="pure">0.091</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235224_TS_1_Member"
      decimals="INF"
      id="ixv-143971"
      unitRef="pure">0.083</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235224_TS_2_Member"
      decimals="INF"
      id="ixv-143972"
      unitRef="pure">0.070</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235224_TS_3_Member"
      decimals="INF"
      id="ixv-143973"
      unitRef="pure">0.057</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235224_TS_4_Member"
      decimals="INF"
      id="ixv-143974"
      unitRef="pure">0.056</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-4568">2024-07-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000240978_ClassMember" id="ixv-4580">Fidelity&#xae; Municipal Core Plus Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000240978_ClassMember" id="ixv-4583">Fidelity Advisor&#xae; Municipal Core Plus Bond Fund Class I</oef:ClassName>
    <dei:TradingSymbol contextRef="C000240978_ClassMember" id="ixv-4587">FMBGX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000240978_ClassMember" id="ixv-4607">This semi-annual shareholder report contains information about Fidelity&#xae; Municipal Core Plus Bond Fund for the period February 1, 2024 to July 31, 2024.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000240978_ClassMember" id="ixv-4609">semi-annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000240978_ClassMember" id="ixv-4614">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-877-208-0098 or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000240978_ClassMember" id="ixv-4616">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000240978_ClassMember" id="ixv-4619">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000240978_ClassMember" id="ixv-4622">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000240978_ClassMember" id="ixv-4629">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What were your Fund costs for the last six months?&lt;/span&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(based on hypothetical $10,000 investment)&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:43%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:25%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs of a $10,000 investment&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:31%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs paid as a percentage of a $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:43%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class I&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:25%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;18&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:31%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;0.37&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000240978_ClassMember"
      decimals="0"
      id="ixv-143975"
      unitRef="usd">18</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000240978_ClassMember"
      decimals="INF"
      id="ixv-143976"
      unitRef="pure">0.0037</oef:ExpenseRatioPct>
    <oef:AddlFundStatisticsTextBlock contextRef="C000240978_ClassMember" id="ixv-4670">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;span style="line-height:16px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of July 31, 2024)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;59,223,606&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;315&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Portfolio Turnover&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;30&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
    <us-gaap:AssetsNet
      contextRef="C000240978_InstantMember"
      decimals="0"
      id="ixv-143977"
      unitRef="usd">59223606</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000240978_InstantMember"
      decimals="INF"
      id="ixv-143978"
      unitRef="holding">315</oef:HoldingsCount>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000240978_ClassMember"
      decimals="INF"
      id="ixv-143979"
      unitRef="pure">0.30</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000240978_ClassMember" id="ixv-4733">
&#160;

REVENUE SOURCES
 (% of Fund's net assets)


Health Care

19.7

&#160;


General Obligations

16.9

&#160;


Transportation

12.2

&#160;


Education

11.3

&#160;


Housing

7.4

&#160;


State G.O.

7.0

&#160;


Special Tax

6.5

&#160;


Others(Individually Less Than 5%)

19.0

&#160;


100.0

&#160;


&#160;




&#160;

AAA

8.1


AA

30.2


A

30.9


BBB

20.6


BB

0.6


B

0.5


Not Rated

5.4


Short-Term Investments and Net Other Assets (Liabilities)

3.7




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;


&#160;


We have used ratings from Moody's Investors Service, Inc. Where Moody's&#xae; ratings are not available, we have used S&amp;P&#xae; ratings. All ratings are as of the date indicated and do not reflect subsequent changes.




&#160;

TOP STATES
(% of Fund's net assets)


Illinois

10.4


New Jersey

8.6


Florida

6.1


Alabama

5.4


Connecticut

5.3


&#160;

&#160;




&#160;
</oef:HoldingsTableTextBlock>
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      id="ixv-143980"
      unitRef="pure">0.197</oef:PctOfNav>
    <oef:PctOfNav
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      id="ixv-143981"
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      id="ixv-143982"
      unitRef="pure">0.122</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-143983"
      unitRef="pure">0.113</oef:PctOfNav>
    <oef:PctOfNav
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      id="ixv-143984"
      unitRef="pure">0.074</oef:PctOfNav>
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      unitRef="pure">0.070</oef:PctOfNav>
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      id="ixv-143986"
      unitRef="pure">0.065</oef:PctOfNav>
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      id="ixv-143987"
      unitRef="pure">0.190</oef:PctOfNav>
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      decimals="INF"
      id="ixv-143988"
      unitRef="pure">0.081</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240978_QD_AA_Member"
      decimals="INF"
      id="ixv-143989"
      unitRef="pure">0.302</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240978_QD_A_Member"
      decimals="INF"
      id="ixv-143990"
      unitRef="pure">0.309</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240978_QD_BBB_Member"
      decimals="INF"
      id="ixv-143991"
      unitRef="pure">0.206</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240978_QD_BB_Member"
      decimals="INF"
      id="ixv-143992"
      unitRef="pure">0.006</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240978_QD_B_Member"
      decimals="INF"
      id="ixv-143993"
      unitRef="pure">0.005</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-143994"
      unitRef="pure">0.054</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240978_QD_ShortTermInvestmentsandNetOtherAssetsLiabilities_Member"
      decimals="INF"
      id="ixv-143995"
      unitRef="pure">0.037</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240978_TS_0_Member"
      decimals="INF"
      id="ixv-143996"
      unitRef="pure">0.104</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240978_TS_1_Member"
      decimals="INF"
      id="ixv-143997"
      unitRef="pure">0.086</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240978_TS_2_Member"
      decimals="INF"
      id="ixv-143998"
      unitRef="pure">0.061</oef:PctOfNav>
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      contextRef="C000240978_TS_3_Member"
      decimals="INF"
      id="ixv-143999"
      unitRef="pure">0.054</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240978_TS_4_Member"
      decimals="INF"
      id="ixv-144000"
      unitRef="pure">0.053</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-5004">2024-07-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000240977_ClassMember" id="ixv-5016">Fidelity&#xae; Municipal Core Plus Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000240977_ClassMember" id="ixv-5019">Fidelity Advisor&#xae; Municipal Core Plus Bond Fund Class Z</oef:ClassName>
    <dei:TradingSymbol contextRef="C000240977_ClassMember" id="ixv-5023">FMBHX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000240977_ClassMember" id="ixv-5043">This semi-annual shareholder report contains information about Fidelity&#xae; Municipal Core Plus Bond Fund for the period February 1, 2024 to July 31, 2024.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000240977_ClassMember" id="ixv-5045">semi-annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000240977_ClassMember" id="ixv-5050">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-877-208-0098 or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000240977_ClassMember" id="ixv-5052">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000240977_ClassMember" id="ixv-5055">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000240977_ClassMember" id="ixv-5058">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000240977_ClassMember" id="ixv-5065">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What were your Fund costs for the last six months?&lt;/span&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(based on hypothetical $10,000 investment)&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:43%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:25%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs of a $10,000 investment&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:31%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs paid as a percentage of a $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:43%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class Z&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:25%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;15&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:31%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;0.31&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000240977_ClassMember"
      decimals="0"
      id="ixv-144001"
      unitRef="usd">15</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000240977_ClassMember"
      decimals="INF"
      id="ixv-144002"
      unitRef="pure">0.0031</oef:ExpenseRatioPct>
    <oef:AddlFundStatisticsTextBlock contextRef="C000240977_ClassMember" id="ixv-5106">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;span style="line-height:16px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of July 31, 2024)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;59,223,606&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;315&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Portfolio Turnover&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;30&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
    <us-gaap:AssetsNet
      contextRef="C000240977_InstantMember"
      decimals="0"
      id="ixv-144003"
      unitRef="usd">59223606</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000240977_InstantMember"
      decimals="INF"
      id="ixv-144004"
      unitRef="holding">315</oef:HoldingsCount>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000240977_ClassMember"
      decimals="INF"
      id="ixv-144005"
      unitRef="pure">0.30</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000240977_ClassMember" id="ixv-5169">
&#160;

REVENUE SOURCES
 (% of Fund's net assets)


Health Care

19.7

&#160;


General Obligations

16.9

&#160;


Transportation

12.2

&#160;


Education

11.3

&#160;


Housing

7.4

&#160;


State G.O.

7.0

&#160;


Special Tax

6.5

&#160;


Others(Individually Less Than 5%)

19.0

&#160;


100.0

&#160;


&#160;




&#160;

AAA

8.1


AA

30.2


A

30.9


BBB

20.6


BB

0.6


B

0.5


Not Rated

5.4


Short-Term Investments and Net Other Assets (Liabilities)

3.7




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;


&#160;


We have used ratings from Moody's Investors Service, Inc. Where Moody's&#xae; ratings are not available, we have used S&amp;P&#xae; ratings. All ratings are as of the date indicated and do not reflect subsequent changes.




&#160;

TOP STATES
(% of Fund's net assets)


Illinois

10.4


New Jersey

8.6


Florida

6.1


Alabama

5.4


Connecticut

5.3


&#160;

&#160;




&#160;
</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000240977_RS_0_Member"
      decimals="INF"
      id="ixv-144006"
      unitRef="pure">0.197</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240977_RS_1_Member"
      decimals="INF"
      id="ixv-144007"
      unitRef="pure">0.169</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240977_RS_2_Member"
      decimals="INF"
      id="ixv-144008"
      unitRef="pure">0.122</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240977_RS_3_Member"
      decimals="INF"
      id="ixv-144009"
      unitRef="pure">0.113</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240977_RS_4_Member"
      decimals="INF"
      id="ixv-144010"
      unitRef="pure">0.074</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240977_RS_5_Member"
      decimals="INF"
      id="ixv-144011"
      unitRef="pure">0.070</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240977_RS_6_Member"
      decimals="INF"
      id="ixv-144012"
      unitRef="pure">0.065</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240977_RS_7_Member"
      decimals="INF"
      id="ixv-144013"
      unitRef="pure">0.190</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240977_QD_AAA_Member"
      decimals="INF"
      id="ixv-144014"
      unitRef="pure">0.081</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240977_QD_AA_Member"
      decimals="INF"
      id="ixv-144015"
      unitRef="pure">0.302</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240977_QD_A_Member"
      decimals="INF"
      id="ixv-144016"
      unitRef="pure">0.309</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240977_QD_BBB_Member"
      decimals="INF"
      id="ixv-144017"
      unitRef="pure">0.206</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240977_QD_BB_Member"
      decimals="INF"
      id="ixv-144018"
      unitRef="pure">0.006</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240977_QD_B_Member"
      decimals="INF"
      id="ixv-144019"
      unitRef="pure">0.005</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240977_QD_NotRated_Member"
      decimals="INF"
      id="ixv-144020"
      unitRef="pure">0.054</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240977_QD_ShortTermInvestmentsandNetOtherAssetsLiabilities_Member"
      decimals="INF"
      id="ixv-144021"
      unitRef="pure">0.037</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240977_TS_0_Member"
      decimals="INF"
      id="ixv-144022"
      unitRef="pure">0.104</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240977_TS_1_Member"
      decimals="INF"
      id="ixv-144023"
      unitRef="pure">0.086</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240977_TS_2_Member"
      decimals="INF"
      id="ixv-144024"
      unitRef="pure">0.061</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240977_TS_3_Member"
      decimals="INF"
      id="ixv-144025"
      unitRef="pure">0.054</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240977_TS_4_Member"
      decimals="INF"
      id="ixv-144026"
      unitRef="pure">0.053</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-5440">2024-07-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000245667_ClassMember" id="ixv-5452">Fidelity&#xae; SAI Conservative Income Municipal Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000245667_ClassMember" id="ixv-5455">Fidelity&#xae; SAI Conservative Income Municipal Bond Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000245667_ClassMember" id="ixv-5459">FSMJX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000245667_ClassMember" id="ixv-5479">This semi-annual shareholder report contains information about Fidelity&#xae; SAI Conservative Income Municipal Bond Fund for the period February 1, 2024 to July 31, 2024.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000245667_ClassMember" id="ixv-5481">semi-annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000245667_ClassMember" id="ixv-5486">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-800-544-3455 or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000245667_ClassMember" id="ixv-5488">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000245667_ClassMember" id="ixv-5491">1-800-544-3455</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000245667_ClassMember" id="ixv-5494">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000245667_ClassMember" id="ixv-5501">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What were your Fund costs for the last six months?&lt;/span&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(based on hypothetical $10,000 investment)&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:43%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:25%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs of a $10,000 investment&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:31%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs paid as a percentage of a $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:43%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; SAI Conservative Income Municipal Bond Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:25%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;10&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:31%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;0.20&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000245667_ClassMember"
      decimals="0"
      id="ixv-144027"
      unitRef="usd">10</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000245667_ClassMember"
      decimals="INF"
      id="ixv-144028"
      unitRef="pure">0.0020</oef:ExpenseRatioPct>
    <oef:AddlFundStatisticsTextBlock contextRef="C000245667_ClassMember" id="ixv-5542">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;span style="line-height:16px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of July 31, 2024)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;1,388,464,065&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;626&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Portfolio Turnover&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;61&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
    <us-gaap:AssetsNet
      contextRef="C000245667_InstantMember"
      decimals="0"
      id="ixv-144029"
      unitRef="usd">1388464065</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000245667_InstantMember"
      decimals="INF"
      id="ixv-144030"
      unitRef="holding">626</oef:HoldingsCount>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000245667_ClassMember"
      decimals="INF"
      id="ixv-144031"
      unitRef="pure">0.61</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000245667_ClassMember" id="ixv-5605">
&#160;

REVENUE SOURCES
 (% of Fund's net assets)


Synthetics

23.9

&#160;


General Obligations

16.3

&#160;


Resource Recovery

9.8

&#160;


Transportation

8.8

&#160;


Industrial Development

8.6

&#160;


Health Care

8.4

&#160;


Electric Utilities

8.0

&#160;


Housing

5.4

&#160;


Others(Individually Less Than 5%)

10.8

&#160;


100.0

&#160;


&#160;




&#160;

AAA

12.4


AA

22.4


A

40.2


BBB

17.8


Not Rated

6.3


Short-Term Investments and Net Other Assets (Liabilities)

0.9




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;


&#160;


We have used ratings from Moody's Investors Service, Inc. Where Moody's&#xae; ratings are not available, we have used S&amp;P&#xae; ratings. All ratings are as of the date indicated and do not reflect subsequent changes.




&#160;

TOP STATES
(% of Fund's net assets)


Texas

12.1


California

9.2


Florida

7.9


Pennsylvania

6.6


Arizona

6.0


&#160;

&#160;




&#160;
</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000245667_RS_0_Member"
      decimals="INF"
      id="ixv-144032"
      unitRef="pure">0.239</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000245667_RS_1_Member"
      decimals="INF"
      id="ixv-144033"
      unitRef="pure">0.163</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000245667_RS_2_Member"
      decimals="INF"
      id="ixv-144034"
      unitRef="pure">0.098</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000245667_RS_3_Member"
      decimals="INF"
      id="ixv-144035"
      unitRef="pure">0.088</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000245667_RS_4_Member"
      decimals="INF"
      id="ixv-144036"
      unitRef="pure">0.086</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000245667_RS_5_Member"
      decimals="INF"
      id="ixv-144037"
      unitRef="pure">0.084</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000245667_RS_6_Member"
      decimals="INF"
      id="ixv-144038"
      unitRef="pure">0.080</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000245667_RS_7_Member"
      decimals="INF"
      id="ixv-144039"
      unitRef="pure">0.054</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000245667_RS_8_Member"
      decimals="INF"
      id="ixv-144040"
      unitRef="pure">0.108</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000245667_QD_AAA_Member"
      decimals="INF"
      id="ixv-144041"
      unitRef="pure">0.124</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000245667_QD_AA_Member"
      decimals="INF"
      id="ixv-144042"
      unitRef="pure">0.224</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000245667_QD_A_Member"
      decimals="INF"
      id="ixv-144043"
      unitRef="pure">0.402</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000245667_QD_BBB_Member"
      decimals="INF"
      id="ixv-144044"
      unitRef="pure">0.178</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000245667_QD_NotRated_Member"
      decimals="INF"
      id="ixv-144045"
      unitRef="pure">0.063</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000245667_QD_ShortTermInvestmentsandNetOtherAssetsLiabilities_Member"
      decimals="INF"
      id="ixv-144046"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000245667_TS_0_Member"
      decimals="INF"
      id="ixv-144047"
      unitRef="pure">0.121</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000245667_TS_1_Member"
      decimals="INF"
      id="ixv-144048"
      unitRef="pure">0.092</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000245667_TS_2_Member"
      decimals="INF"
      id="ixv-144049"
      unitRef="pure">0.079</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000245667_TS_3_Member"
      decimals="INF"
      id="ixv-144050"
      unitRef="pure">0.066</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000245667_TS_4_Member"
      decimals="INF"
      id="ixv-144051"
      unitRef="pure">0.060</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-5873">2024-07-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000235227_ClassMember" id="ixv-5885">Fidelity&#xae; Sustainable Intermediate Municipal Income Fund</oef:FundName>
    <oef:ClassName contextRef="C000235227_ClassMember" id="ixv-5888">Fidelity Advisor&#xae; Sustainable Intermediate Municipal Income Fund Class Z</oef:ClassName>
    <dei:TradingSymbol contextRef="C000235227_ClassMember" id="ixv-5892">FASVX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000235227_ClassMember" id="ixv-5912">This semi-annual shareholder report contains information about Fidelity&#xae; Sustainable Intermediate Municipal Income Fund for the period February 1, 2024 to July 31, 2024.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000235227_ClassMember" id="ixv-5914">semi-annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000235227_ClassMember" id="ixv-5919">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-877-208-0098 or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000235227_ClassMember" id="ixv-5921">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000235227_ClassMember" id="ixv-5924">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000235227_ClassMember" id="ixv-5927">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000235227_ClassMember" id="ixv-5934">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What were your Fund costs for the last six months?&lt;/span&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(based on hypothetical $10,000 investment)&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:43%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:25%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs of a $10,000 investment&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:31%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs paid as a percentage of a $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:43%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class Z&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:25%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;15&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:31%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;0.31&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000235227_ClassMember"
      decimals="0"
      id="ixv-144052"
      unitRef="usd">15</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000235227_ClassMember"
      decimals="INF"
      id="ixv-144053"
      unitRef="pure">0.0031</oef:ExpenseRatioPct>
    <oef:AddlFundStatisticsTextBlock contextRef="C000235227_ClassMember" id="ixv-5975">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;span style="line-height:16px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of July 31, 2024)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;15,835,114&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;249&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Portfolio Turnover&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;15&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
    <us-gaap:AssetsNet
      contextRef="C000235227_InstantMember"
      decimals="0"
      id="ixv-144054"
      unitRef="usd">15835114</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000235227_InstantMember"
      decimals="INF"
      id="ixv-144055"
      unitRef="holding">249</oef:HoldingsCount>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000235227_ClassMember"
      decimals="INF"
      id="ixv-144056"
      unitRef="pure">0.15</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000235227_ClassMember" id="ixv-6038">
&#160;

REVENUE SOURCES
 (% of Fund's net assets)


Health Care

21.2

&#160;


General Obligations

21.1

&#160;


Education

16.3

&#160;


Electric Utilities

9.6

&#160;


Housing

8.1

&#160;


State G.O.

6.7

&#160;


Special Tax

5.6

&#160;


Others(Individually Less Than 5%)

11.4

&#160;


100.0

&#160;


&#160;




&#160;

AAA

8.9


AA

41.8


A

32.1


BBB

17.0


BB

0.3


Not Rated

0.1




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;


Short-Term Investments and Net Other Assets (Liabilities) - (0.2)%*


&#160;


We have used ratings from Moody's Investors Service, Inc. Where Moody's&#xae; ratings are not available, we have used S&amp;P&#xae; ratings. All ratings are as of the date indicated and do not reflect subsequent changes.




&#160;

TOP STATES
(% of Fund's net assets)


New York

9.1


Illinois

8.3


California

7.0


Florida

5.7


Georgia

5.6


&#160;

&#160;




&#160;
</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000235227_RS_0_Member"
      decimals="INF"
      id="ixv-144057"
      unitRef="pure">0.212</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235227_RS_1_Member"
      decimals="INF"
      id="ixv-144058"
      unitRef="pure">0.211</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235227_RS_2_Member"
      decimals="INF"
      id="ixv-144059"
      unitRef="pure">0.163</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235227_RS_3_Member"
      decimals="INF"
      id="ixv-144060"
      unitRef="pure">0.096</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235227_RS_4_Member"
      decimals="INF"
      id="ixv-144061"
      unitRef="pure">0.081</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235227_RS_5_Member"
      decimals="INF"
      id="ixv-144062"
      unitRef="pure">0.067</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235227_RS_6_Member"
      decimals="INF"
      id="ixv-144063"
      unitRef="pure">0.056</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235227_RS_7_Member"
      decimals="INF"
      id="ixv-144064"
      unitRef="pure">0.114</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235227_QD_AAA_Member"
      decimals="INF"
      id="ixv-144065"
      unitRef="pure">0.089</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235227_QD_AA_Member"
      decimals="INF"
      id="ixv-144066"
      unitRef="pure">0.418</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235227_QD_A_Member"
      decimals="INF"
      id="ixv-144067"
      unitRef="pure">0.321</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235227_QD_BBB_Member"
      decimals="INF"
      id="ixv-144068"
      unitRef="pure">0.170</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235227_QD_BB_Member"
      decimals="INF"
      id="ixv-144069"
      unitRef="pure">0.003</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235227_QD_NotRated_Member"
      decimals="INF"
      id="ixv-144070"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235227_TS_0_Member"
      decimals="INF"
      id="ixv-144071"
      unitRef="pure">0.091</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235227_TS_1_Member"
      decimals="INF"
      id="ixv-144072"
      unitRef="pure">0.083</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235227_TS_2_Member"
      decimals="INF"
      id="ixv-144073"
      unitRef="pure">0.070</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235227_TS_3_Member"
      decimals="INF"
      id="ixv-144074"
      unitRef="pure">0.057</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235227_TS_4_Member"
      decimals="INF"
      id="ixv-144075"
      unitRef="pure">0.056</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-6301">2024-07-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000235216_ClassMember" id="ixv-6313">Fidelity&#xae; SAI Sustainable Municipal Income Fund</oef:FundName>
    <oef:ClassName contextRef="C000235216_ClassMember" id="ixv-6316">Fidelity&#xae; SAI Sustainable Municipal Income Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000235216_ClassMember" id="ixv-6320">FASWX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000235216_ClassMember" id="ixv-6340">This semi-annual shareholder report contains information about Fidelity&#xae; SAI Sustainable Municipal Income Fund for the period February 1, 2024 to July 31, 2024.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000235216_ClassMember" id="ixv-6342">semi-annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000235216_ClassMember" id="ixv-6347">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-800-544-3455 or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000235216_ClassMember" id="ixv-6349">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000235216_ClassMember" id="ixv-6352">1-800-544-3455</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000235216_ClassMember" id="ixv-6355">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000235216_ClassMember" id="ixv-6362">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What were your Fund costs for the last six months?&lt;/span&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(based on hypothetical $10,000 investment)&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:43%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:25%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs of a $10,000 investment&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:31%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs paid as a percentage of a $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:43%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; SAI Sustainable Municipal Income Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:25%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;18&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:31%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;0.36&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000235216_ClassMember"
      decimals="0"
      id="ixv-144076"
      unitRef="usd">18</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000235216_ClassMember"
      decimals="INF"
      id="ixv-144077"
      unitRef="pure">0.0036</oef:ExpenseRatioPct>
    <oef:AddlFundStatisticsTextBlock contextRef="C000235216_ClassMember" id="ixv-6403">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;span style="line-height:16px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of July 31, 2024)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;26,698,208&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;280&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Portfolio Turnover&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;0&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:6px;color:#000000;font-style:normal;vertical-align:super;font-weight:normal;"&gt;A&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:6px;color:#000000;font-style:normal;vertical-align:super;font-weight:normal;"&gt;A &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans Cd';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Amount represents less than 1%&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
    <us-gaap:AssetsNet
      contextRef="C000235216_InstantMember"
      decimals="0"
      id="ixv-144078"
      unitRef="usd">26698208</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000235216_InstantMember"
      decimals="INF"
      id="ixv-144079"
      unitRef="holding">280</oef:HoldingsCount>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000235216_ClassMember"
      decimals="INF"
      id="ixv-144080"
      unitRef="pure">0</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000235216_ClassMember" id="ixv-6470">
&#160;

REVENUE SOURCES
 (% of Fund's net assets)


General Obligations

31.0

&#160;


Health Care

22.7

&#160;


Education

15.9

&#160;


Water &amp; Sewer

9.4

&#160;


Special Tax

6.4

&#160;


Electric Utilities

5.0

&#160;


Others(Individually Less Than 5%)

9.6

&#160;


100.0

&#160;


&#160;




&#160;

AAA

7.6


AA

50.7


A

30.1


BBB

12.1


BB

0.2


Not Rated

0.2




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;


Short-Term Investments and Net Other Assets (Liabilities) - (0.9)%*


&#160;


We have used ratings from Moody's Investors Service, Inc. Where Moody's&#xae; ratings are not available, we have used S&amp;P&#xae; ratings. All ratings are as of the date indicated and do not reflect subsequent changes.




&#160;

TOP STATES
(% of Fund's net assets)


California

12.6


Florida

9.6


New York

8.5


Massachusetts

8.5


Illinois

6.7


&#160;

&#160;




&#160;
</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000235216_RS_0_Member"
      decimals="INF"
      id="ixv-144081"
      unitRef="pure">0.310</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235216_RS_1_Member"
      decimals="INF"
      id="ixv-144082"
      unitRef="pure">0.227</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235216_RS_2_Member"
      decimals="INF"
      id="ixv-144083"
      unitRef="pure">0.159</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235216_RS_3_Member"
      decimals="INF"
      id="ixv-144084"
      unitRef="pure">0.094</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235216_RS_4_Member"
      decimals="INF"
      id="ixv-144085"
      unitRef="pure">0.064</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235216_RS_5_Member"
      decimals="INF"
      id="ixv-144086"
      unitRef="pure">0.050</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235216_RS_6_Member"
      decimals="INF"
      id="ixv-144087"
      unitRef="pure">0.096</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235216_QD_AAA_Member"
      decimals="INF"
      id="ixv-144088"
      unitRef="pure">0.076</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235216_QD_AA_Member"
      decimals="INF"
      id="ixv-144089"
      unitRef="pure">0.507</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235216_QD_A_Member"
      decimals="INF"
      id="ixv-144090"
      unitRef="pure">0.301</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235216_QD_BBB_Member"
      decimals="INF"
      id="ixv-144091"
      unitRef="pure">0.121</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235216_QD_BB_Member"
      decimals="INF"
      id="ixv-144092"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235216_QD_NotRated_Member"
      decimals="INF"
      id="ixv-144093"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235216_TS_0_Member"
      decimals="INF"
      id="ixv-144094"
      unitRef="pure">0.126</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235216_TS_1_Member"
      decimals="INF"
      id="ixv-144095"
      unitRef="pure">0.096</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235216_TS_2_Member"
      decimals="INF"
      id="ixv-144096"
      unitRef="pure">0.085</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235216_TS_3_Member"
      decimals="INF"
      id="ixv-144097"
      unitRef="pure">0.085</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235216_TS_4_Member"
      decimals="INF"
      id="ixv-144098"
      unitRef="pure">0.067</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-6724">2024-07-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000240982_ClassMember" id="ixv-6736">Fidelity&#xae; Municipal Core Plus Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000240982_ClassMember" id="ixv-6739">Fidelity Advisor&#xae; Municipal Core Plus Bond Fund Class C</oef:ClassName>
    <dei:TradingSymbol contextRef="C000240982_ClassMember" id="ixv-6743">FMBEX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000240982_ClassMember" id="ixv-6763">This semi-annual shareholder report contains information about Fidelity&#xae; Municipal Core Plus Bond Fund for the period February 1, 2024 to July 31, 2024.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000240982_ClassMember" id="ixv-6765">semi-annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000240982_ClassMember" id="ixv-6770">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-877-208-0098 or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000240982_ClassMember" id="ixv-6772">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000240982_ClassMember" id="ixv-6775">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000240982_ClassMember" id="ixv-6778">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000240982_ClassMember" id="ixv-6785">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What were your Fund costs for the last six months?&lt;/span&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(based on hypothetical $10,000 investment)&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:43%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:25%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs of a $10,000 investment&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:31%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs paid as a percentage of a $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:43%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class C&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:25%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;68&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:31%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;1.37&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
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      decimals="INF"
      id="ixv-144100"
      unitRef="pure">0.0137</oef:ExpenseRatioPct>
    <oef:AddlFundStatisticsTextBlock contextRef="C000240982_ClassMember" id="ixv-6826">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;span style="line-height:16px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of July 31, 2024)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;59,223,606&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;315&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Portfolio Turnover&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;30&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
    <us-gaap:AssetsNet
      contextRef="C000240982_InstantMember"
      decimals="0"
      id="ixv-144101"
      unitRef="usd">59223606</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000240982_InstantMember"
      decimals="INF"
      id="ixv-144102"
      unitRef="holding">315</oef:HoldingsCount>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000240982_ClassMember"
      decimals="INF"
      id="ixv-144103"
      unitRef="pure">0.30</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000240982_ClassMember" id="ixv-6889">
&#160;

REVENUE SOURCES
 (% of Fund's net assets)


Health Care

19.7

&#160;


General Obligations

16.9

&#160;


Transportation

12.2

&#160;


Education

11.3

&#160;


Housing

7.4

&#160;


State G.O.

7.0

&#160;


Special Tax

6.5

&#160;


Others(Individually Less Than 5%)

19.0

&#160;


100.0

&#160;


&#160;




&#160;

AAA

8.1


AA

30.2


A

30.9


BBB

20.6


BB

0.6


B

0.5


Not Rated

5.4


Short-Term Investments and Net Other Assets (Liabilities)

3.7




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;


&#160;


We have used ratings from Moody's Investors Service, Inc. Where Moody's&#xae; ratings are not available, we have used S&amp;P&#xae; ratings. All ratings are as of the date indicated and do not reflect subsequent changes.




&#160;

TOP STATES
(% of Fund's net assets)


Illinois

10.4


New Jersey

8.6


Florida

6.1


Alabama

5.4


Connecticut

5.3


&#160;

&#160;




&#160;
</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000240982_RS_0_Member"
      decimals="INF"
      id="ixv-144104"
      unitRef="pure">0.197</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240982_RS_1_Member"
      decimals="INF"
      id="ixv-144105"
      unitRef="pure">0.169</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240982_RS_2_Member"
      decimals="INF"
      id="ixv-144106"
      unitRef="pure">0.122</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240982_RS_3_Member"
      decimals="INF"
      id="ixv-144107"
      unitRef="pure">0.113</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240982_RS_4_Member"
      decimals="INF"
      id="ixv-144108"
      unitRef="pure">0.074</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240982_RS_5_Member"
      decimals="INF"
      id="ixv-144109"
      unitRef="pure">0.070</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240982_RS_6_Member"
      decimals="INF"
      id="ixv-144110"
      unitRef="pure">0.065</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240982_RS_7_Member"
      decimals="INF"
      id="ixv-144111"
      unitRef="pure">0.190</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240982_QD_AAA_Member"
      decimals="INF"
      id="ixv-144112"
      unitRef="pure">0.081</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240982_QD_AA_Member"
      decimals="INF"
      id="ixv-144113"
      unitRef="pure">0.302</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240982_QD_A_Member"
      decimals="INF"
      id="ixv-144114"
      unitRef="pure">0.309</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240982_QD_BBB_Member"
      decimals="INF"
      id="ixv-144115"
      unitRef="pure">0.206</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240982_QD_BB_Member"
      decimals="INF"
      id="ixv-144116"
      unitRef="pure">0.006</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240982_QD_B_Member"
      decimals="INF"
      id="ixv-144117"
      unitRef="pure">0.005</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240982_QD_NotRated_Member"
      decimals="INF"
      id="ixv-144118"
      unitRef="pure">0.054</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240982_QD_ShortTermInvestmentsandNetOtherAssetsLiabilities_Member"
      decimals="INF"
      id="ixv-144119"
      unitRef="pure">0.037</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240982_TS_0_Member"
      decimals="INF"
      id="ixv-144120"
      unitRef="pure">0.104</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240982_TS_1_Member"
      decimals="INF"
      id="ixv-144121"
      unitRef="pure">0.086</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240982_TS_2_Member"
      decimals="INF"
      id="ixv-144122"
      unitRef="pure">0.061</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240982_TS_3_Member"
      decimals="INF"
      id="ixv-144123"
      unitRef="pure">0.054</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240982_TS_4_Member"
      decimals="INF"
      id="ixv-144124"
      unitRef="pure">0.053</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-7160">2024-07-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000235226_ClassMember" id="ixv-7172">Fidelity&#xae; Sustainable Intermediate Municipal Income Fund</oef:FundName>
    <oef:ClassName contextRef="C000235226_ClassMember" id="ixv-7175">Fidelity Advisor&#xae; Sustainable Intermediate Municipal Income Fund Class I</oef:ClassName>
    <dei:TradingSymbol contextRef="C000235226_ClassMember" id="ixv-7179">FASUX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000235226_ClassMember" id="ixv-7199">This semi-annual shareholder report contains information about Fidelity&#xae; Sustainable Intermediate Municipal Income Fund for the period February 1, 2024 to July 31, 2024.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000235226_ClassMember" id="ixv-7201">semi-annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000235226_ClassMember" id="ixv-7206">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-877-208-0098 or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000235226_ClassMember" id="ixv-7208">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000235226_ClassMember" id="ixv-7211">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000235226_ClassMember" id="ixv-7214">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000235226_ClassMember" id="ixv-7221">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What were your Fund costs for the last six months?&lt;/span&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(based on hypothetical $10,000 investment)&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:43%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:25%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs of a $10,000 investment&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:31%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs paid as a percentage of a $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:43%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class I&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:25%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;18&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:31%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;0.37&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000235226_ClassMember"
      decimals="0"
      id="ixv-144125"
      unitRef="usd">18</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000235226_ClassMember"
      decimals="INF"
      id="ixv-144126"
      unitRef="pure">0.0037</oef:ExpenseRatioPct>
    <oef:AddlFundStatisticsTextBlock contextRef="C000235226_ClassMember" id="ixv-7262">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;span style="line-height:16px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of July 31, 2024)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;15,835,114&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;249&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Portfolio Turnover&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;15&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
    <us-gaap:AssetsNet
      contextRef="C000235226_InstantMember"
      decimals="0"
      id="ixv-144127"
      unitRef="usd">15835114</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000235226_InstantMember"
      decimals="INF"
      id="ixv-144128"
      unitRef="holding">249</oef:HoldingsCount>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000235226_ClassMember"
      decimals="INF"
      id="ixv-144129"
      unitRef="pure">0.15</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000235226_ClassMember" id="ixv-7325">
&#160;

REVENUE SOURCES
 (% of Fund's net assets)


Health Care

21.2

&#160;


General Obligations

21.1

&#160;


Education

16.3

&#160;


Electric Utilities

9.6

&#160;


Housing

8.1

&#160;


State G.O.

6.7

&#160;


Special Tax

5.6

&#160;


Others(Individually Less Than 5%)

11.4

&#160;


100.0

&#160;


&#160;




&#160;

AAA

8.9


AA

41.8


A

32.1


BBB

17.0


BB

0.3


Not Rated

0.1




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;


Short-Term Investments and Net Other Assets (Liabilities) - (0.2)%*


&#160;


We have used ratings from Moody's Investors Service, Inc. Where Moody's&#xae; ratings are not available, we have used S&amp;P&#xae; ratings. All ratings are as of the date indicated and do not reflect subsequent changes.




&#160;

TOP STATES
(% of Fund's net assets)


New York

9.1


Illinois

8.3


California

7.0


Florida

5.7


Georgia

5.6


&#160;

&#160;




&#160;
</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000235226_RS_0_Member"
      decimals="INF"
      id="ixv-144130"
      unitRef="pure">0.212</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235226_RS_1_Member"
      decimals="INF"
      id="ixv-144131"
      unitRef="pure">0.211</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235226_RS_2_Member"
      decimals="INF"
      id="ixv-144132"
      unitRef="pure">0.163</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235226_RS_3_Member"
      decimals="INF"
      id="ixv-144133"
      unitRef="pure">0.096</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235226_RS_4_Member"
      decimals="INF"
      id="ixv-144134"
      unitRef="pure">0.081</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235226_RS_5_Member"
      decimals="INF"
      id="ixv-144135"
      unitRef="pure">0.067</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235226_RS_6_Member"
      decimals="INF"
      id="ixv-144136"
      unitRef="pure">0.056</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235226_RS_7_Member"
      decimals="INF"
      id="ixv-144137"
      unitRef="pure">0.114</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235226_QD_AAA_Member"
      decimals="INF"
      id="ixv-144138"
      unitRef="pure">0.089</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235226_QD_AA_Member"
      decimals="INF"
      id="ixv-144139"
      unitRef="pure">0.418</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235226_QD_A_Member"
      decimals="INF"
      id="ixv-144140"
      unitRef="pure">0.321</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235226_QD_BBB_Member"
      decimals="INF"
      id="ixv-144141"
      unitRef="pure">0.170</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235226_QD_BB_Member"
      decimals="INF"
      id="ixv-144142"
      unitRef="pure">0.003</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235226_QD_NotRated_Member"
      decimals="INF"
      id="ixv-144143"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235226_TS_0_Member"
      decimals="INF"
      id="ixv-144144"
      unitRef="pure">0.091</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235226_TS_1_Member"
      decimals="INF"
      id="ixv-144145"
      unitRef="pure">0.083</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235226_TS_2_Member"
      decimals="INF"
      id="ixv-144146"
      unitRef="pure">0.070</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235226_TS_3_Member"
      decimals="INF"
      id="ixv-144147"
      unitRef="pure">0.057</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000235226_TS_4_Member"
      decimals="INF"
      id="ixv-144148"
      unitRef="pure">0.056</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-7588">2024-07-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000240979_ClassMember" id="ixv-7600">Fidelity&#xae; Municipal Core Plus Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000240979_ClassMember" id="ixv-7603">Fidelity&#xae; Municipal Core Plus Bond Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000240979_ClassMember" id="ixv-7607">FMBAX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000240979_ClassMember" id="ixv-7627">This semi-annual shareholder report contains information about Fidelity&#xae; Municipal Core Plus Bond Fund for the period February 1, 2024 to July 31, 2024.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000240979_ClassMember" id="ixv-7629">semi-annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000240979_ClassMember" id="ixv-7634">You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-800-544-8544 or by sending an e-mail to fidfunddocuments@fidelity.com.</oef:AddlInfoTextBlock>
    <oef:AddlInfoWebsite contextRef="C000240979_ClassMember" id="ixv-7636">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000240979_ClassMember" id="ixv-7639">1-800-544-8544</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000240979_ClassMember" id="ixv-7642">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000240979_ClassMember" id="ixv-7649">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What were your Fund costs for the last six months?&lt;/span&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(based on hypothetical $10,000 investment)&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:43%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:25%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs of a $10,000 investment&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:31%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs paid as a percentage of a $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:43%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Municipal Core Plus Bond Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:25%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;18&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:31%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;0.37&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000240979_ClassMember"
      decimals="0"
      id="ixv-144149"
      unitRef="usd">18</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000240979_ClassMember"
      decimals="INF"
      id="ixv-144150"
      unitRef="pure">0.0037</oef:ExpenseRatioPct>
    <oef:AddlFundStatisticsTextBlock contextRef="C000240979_ClassMember" id="ixv-7690">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;span style="line-height:16px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of July 31, 2024)&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:11px;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;table cellpadding="0" cellspacing="1" style="border-collapse:separate;border-style:none;margin:auto;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:63%; " valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:bold;"&gt;KEY FACTS&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;59,223,606&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;315&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Portfolio Turnover&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;30&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
    <us-gaap:AssetsNet
      contextRef="C000240979_InstantMember"
      decimals="0"
      id="ixv-144151"
      unitRef="usd">59223606</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000240979_InstantMember"
      decimals="INF"
      id="ixv-144152"
      unitRef="holding">315</oef:HoldingsCount>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000240979_ClassMember"
      decimals="INF"
      id="ixv-144153"
      unitRef="pure">0.30</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000240979_ClassMember" id="ixv-7753">
&#160;

REVENUE SOURCES
 (% of Fund's net assets)


Health Care

19.7

&#160;


General Obligations

16.9

&#160;


Transportation

12.2

&#160;


Education

11.3

&#160;


Housing

7.4

&#160;


State G.O.

7.0

&#160;


Special Tax

6.5

&#160;


Others(Individually Less Than 5%)

19.0

&#160;


100.0

&#160;


&#160;




&#160;

AAA

8.1


AA

30.2


A

30.9


BBB

20.6


BB

0.6


B

0.5


Not Rated

5.4


Short-Term Investments and Net Other Assets (Liabilities)

3.7




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;


&#160;


We have used ratings from Moody's Investors Service, Inc. Where Moody's&#xae; ratings are not available, we have used S&amp;P&#xae; ratings. All ratings are as of the date indicated and do not reflect subsequent changes.




&#160;

TOP STATES
(% of Fund's net assets)


Illinois

10.4


New Jersey

8.6


Florida

6.1


Alabama

5.4


Connecticut

5.3


&#160;

&#160;




&#160;
</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000240979_RS_0_Member"
      decimals="INF"
      id="ixv-144154"
      unitRef="pure">0.197</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240979_RS_1_Member"
      decimals="INF"
      id="ixv-144155"
      unitRef="pure">0.169</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240979_RS_2_Member"
      decimals="INF"
      id="ixv-144156"
      unitRef="pure">0.122</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240979_RS_3_Member"
      decimals="INF"
      id="ixv-144157"
      unitRef="pure">0.113</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240979_RS_4_Member"
      decimals="INF"
      id="ixv-144158"
      unitRef="pure">0.074</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240979_RS_5_Member"
      decimals="INF"
      id="ixv-144159"
      unitRef="pure">0.070</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240979_RS_6_Member"
      decimals="INF"
      id="ixv-144160"
      unitRef="pure">0.065</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240979_RS_7_Member"
      decimals="INF"
      id="ixv-144161"
      unitRef="pure">0.190</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000240979_QD_AAA_Member"
      decimals="INF"
      id="ixv-144162"
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