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    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000069436_ClassMember" id="ixv-139">This annual shareholder report contains information about Fidelity&#xae; Series Investment Grade Bond Fund for the period September 1, 2023 to August 31, 2024.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000069436_ClassMember" id="ixv-141">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000069436_ClassMember" id="ixv-146">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="C000069436_ClassMember" id="ixv-148">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
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&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&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;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;FUND COST (PREVIOUS YEAR)&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:45%; 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:24%; 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:30%; 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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:45%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Series Investment Grade Bond Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:24%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &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:30%; 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;
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&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>
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    <oef:FactorsAffectingPerfTextBlock contextRef="C000069436_ClassMember" id="ixv-211">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&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:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds posted a strong advance for the 12 months ending August 31, 2024, helped by a late-period gain as the bond market reflected anticipated interest-rate reductions by the U.S. Federal Reserve, which are expected to start in September. The full 12-month period was marked by high levels of volatility.&#160;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, both sector allocation and security selection contributed to the fund's outperformance of the Bloomberg U.S. Aggregate Bond Index for the fiscal year.&#160;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In terms of sector allocation, the fund's overweights in asset-backed securities, mortgage-backed securities and commercial mortgage-backed securities segments each helped relative performance the past 12 months.&#160;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;As for security selection, fund holdings in the corporate segment made a notable contribution, led by picks among financials, particularly REITs and banks.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Picks among MBS also helped relative performance this period, as did choices among ABS, with fund holdings in collateralized loan obligations providing a boost. Security selection among CMBS were beneficial as well.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In contrast, the fund's underweight in industrial bonds within the corporate sector detracted versus the index the past 12 months.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000069436_ClassMember" id="ixv-235">How did the Fund perform over the past 10 years?
&#160;
 &#160;&#160;
CUMULATIVE PERFORMANCE
August 31, 2014 through August 31, 2024.
Initial investment of $10,000.

Fidelity&#xae; Series Investment Grade Bond Fund
&#160;

$10,000

$10,079
&#160;

$10,771
&#160;

$10,927
&#160;

$10,878
&#160;

$11,983
&#160;

$12,962
&#160;

$13,229
&#160;

$11,759
&#160;

$11,757
&#160;

$12,732
&#160;


Bloomberg U.S. Aggregate Bond Index
&#160;

$10,000

$10,156
&#160;

$10,761
&#160;

$10,814
&#160;

$10,701
&#160;

$11,789
&#160;

$12,553
&#160;

$12,542
&#160;

$11,098
&#160;

$10,965
&#160;

$11,765
&#160;


&#160;

2014

2015

2016

2017

2018

2019

2020

2021

2022

2023

2024









</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000069436_LG_ClassMember_11YR" id="ixv-254">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Series Investment Grade Bond Fund&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AcctVal
      contextRef="C000069436_ClassMember_AsOf_2014"
      decimals="0"
      id="ixv-257732"
      unitRef="usd">10000</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000069436_ClassMember_AsOf_2015"
      decimals="0"
      id="ixv-257733"
      unitRef="usd">10079</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000069436_ClassMember_AsOf_2016"
      decimals="0"
      id="ixv-257734"
      unitRef="usd">10771</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000069436_ClassMember_AsOf_2017"
      decimals="0"
      id="ixv-257735"
      unitRef="usd">10927</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000069436_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-257736"
      unitRef="usd">10878</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000069436_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-257737"
      unitRef="usd">11983</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000069436_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-257738"
      unitRef="usd">12962</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000069436_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-257739"
      unitRef="usd">13229</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000069436_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-257740"
      unitRef="usd">11759</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000069436_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-257741"
      unitRef="usd">11757</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000069436_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-257742"
      unitRef="usd">12732</oef:AcctVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000069436_LG_1_AdditionalIndexMember_11YR"
      id="ixv-314">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AcctVal
      contextRef="C000069436_1_AdditionalIndexMember_AsOf_2014"
      decimals="0"
      id="ixv-257743"
      unitRef="usd">10000</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000069436_1_AdditionalIndexMember_AsOf_2015"
      decimals="0"
      id="ixv-257744"
      unitRef="usd">10156</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000069436_1_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-257745"
      unitRef="usd">10761</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000069436_1_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-257746"
      unitRef="usd">10814</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000069436_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-257747"
      unitRef="usd">10701</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000069436_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-257748"
      unitRef="usd">11789</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000069436_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-257749"
      unitRef="usd">12553</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000069436_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-257750"
      unitRef="usd">12542</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000069436_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-257751"
      unitRef="usd">11098</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000069436_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-257752"
      unitRef="usd">10965</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000069436_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-257753"
      unitRef="usd">11765</oef:AcctVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000069436_ClassMember" id="ixv-423">AVERAGE ANNUAL TOTAL RETURNS:
&#160;
&#160;

1 Year

5 Year

10 Year


Fidelity&#xae; Series Investment Grade Bond Fund

8.29%

1.22%

2.44%


Bloomberg U.S. Aggregate Bond Index

7.30%

-0.04%

1.64%




&#160;
Visit www.fidelity.com for more recent performance information.
&#160;


The Fund's past performance is not a good predictor of the Fund's future performance. &#160;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
&#160;



</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
      contextRef="C000069436_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-257754"
      unitRef="pure">0.0829</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000069436_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-257755"
      unitRef="pure">0.0122</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000069436_NoLoadClassMember_10YR"
      decimals="INF"
      id="ixv-257756"
      unitRef="pure">0.0244</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000069436_0_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-257757"
      unitRef="pure">0.0730</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000069436_0_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-257758"
      unitRef="pure">-0.0004</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000069436_0_BBIndexMember_10YR"
      decimals="INF"
      id="ixv-257759"
      unitRef="pure">0.0164</oef:AvgAnnlRtrPct>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000069436_ClassMember" id="ixv-484">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span&gt;</oef:PerformancePastDoesNotIndicateFuture>
    <oef:NoDeductionOfTaxesTextBlock contextRef="C000069436_ClassMember" id="ixv-488">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.&lt;/span&gt;</oef:NoDeductionOfTaxesTextBlock>
    <oef:AddlFundStatisticsTextBlock contextRef="C000069436_ClassMember" id="ixv-495">&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 August 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;/div&gt;
&lt;span style="line-height:11px;"&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:bold;"&gt; &lt;span&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/div&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;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;$&lt;/span&gt;36,297,786,651&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;5,101&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;0&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="middle"&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;219&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="C000069436_InstantMember"
      decimals="0"
      id="ixv-257760"
      unitRef="usd">36297786651</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000069436_InstantMember"
      decimals="INF"
      id="ixv-257761"
      unitRef="holding">5101</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
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      decimals="0"
      id="ixv-257762"
      unitRef="usd">0</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000069436_ClassMember"
      decimals="INF"
      id="ixv-257763"
      unitRef="pure">2.19</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000069436_ClassMember" id="ixv-576">
&#160;

U.S. Government and U.S. Government Agency Obligations

64.1


AAA

9.3


AA

0.6


A

7.8


BBB

16.6


BB

2.4


B

1.1


CCC,CC,C

0.0


Not Rated

4.5




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;


Short-Term Investments and Net Other Assets (Liabilities) - (6.4)%


&#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;
&#160;

U.S. Treasury Obligations

39.4


Corporate Bonds

25.6


U.S. Government Agency - Mortgage Securities

24.7


Asset-Backed Securities

8.6


CMOs and Other Mortgage Related Securities

7.9


Other Investments

0.2


Foreign Government and Government Agency Obligations

0.0


Preferred Securities

0.0




ASSET ALLOCATION (% of Fund's net assets)


&#160;


Short-Term Investments and Net Other Assets (Liabilities) - (6.4)%








United States

90.1


Grand Cayman (UK Overseas Ter)

4.5


United Kingdom

1.3


Mexico

1.1


Ireland

0.7


Switzerland

0.6


Germany

0.5


France

0.3


Canada

0.2


Others

0.7




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;


&#160;







</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000069436_QD_USGovernmentandUSGovernmentAgencyObligations_Member"
      decimals="INF"
      id="ixv-257764"
      unitRef="pure">0.641</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000069436_QD_AAA_Member"
      decimals="INF"
      id="ixv-257765"
      unitRef="pure">0.093</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000069436_QD_AA_Member"
      decimals="INF"
      id="ixv-257766"
      unitRef="pure">0.006</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000069436_QD_A_Member"
      decimals="INF"
      id="ixv-257767"
      unitRef="pure">0.078</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000069436_QD_BBB_Member"
      decimals="INF"
      id="ixv-257768"
      unitRef="pure">0.166</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000069436_QD_BB_Member"
      decimals="INF"
      id="ixv-257769"
      unitRef="pure">0.024</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000069436_QD_B_Member"
      decimals="INF"
      id="ixv-257770"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000069436_QD_CCCCCC_Member"
      decimals="INF"
      id="ixv-257771"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000069436_QD_NotRated_Member"
      decimals="INF"
      id="ixv-257772"
      unitRef="pure">0.045</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000069436_AA_USTreasuryObligations_Member"
      decimals="INF"
      id="ixv-257773"
      unitRef="pure">0.394</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000069436_AA_CorporateBonds_Member"
      decimals="INF"
      id="ixv-257774"
      unitRef="pure">0.256</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000069436_AA_USGovernmentAgencyMortgageSecurities_Member"
      decimals="INF"
      id="ixv-257775"
      unitRef="pure">0.247</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000069436_AA_AssetBackedSecurities_Member"
      decimals="INF"
      id="ixv-257776"
      unitRef="pure">0.086</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000069436_AA_CMOsandOtherMortgageRelatedSecurities_Member"
      decimals="INF"
      id="ixv-257777"
      unitRef="pure">0.079</oef:PctOfNav>
    <oef:PctOfNav
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      id="ixv-257778"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-257779"
      unitRef="pure">0.000</oef:PctOfNav>
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      contextRef="C000069436_AA_PreferredSecurities_Member"
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      id="ixv-257780"
      unitRef="pure">0.000</oef:PctOfNav>
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      contextRef="C000069436_GD_GrandCaymanUKOverseasTer_Member"
      decimals="INF"
      id="ixv-257782"
      unitRef="pure">0.045</oef:PctOfNav>
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      contextRef="C000069436_GD_GB_Member"
      decimals="INF"
      id="ixv-257783"
      unitRef="pure">0.013</oef:PctOfNav>
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      contextRef="C000069436_GD_MX_Member"
      decimals="INF"
      id="ixv-257784"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000069436_GD_IE_Member"
      decimals="INF"
      id="ixv-257785"
      unitRef="pure">0.007</oef:PctOfNav>
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      unitRef="pure">0.006</oef:PctOfNav>
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      decimals="INF"
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      unitRef="pure">0.005</oef:PctOfNav>
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      contextRef="C000069436_GD_FR_Member"
      decimals="INF"
      id="ixv-257788"
      unitRef="pure">0.003</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000069436_GD_CA_Member"
      decimals="INF"
      id="ixv-257789"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-257790"
      unitRef="pure">0.007</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000069436_ClassMember" id="ixv-824">
TOP HOLDINGS
(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

29.4
&#160;

&#160;


US Treasury Bonds

10.0
&#160;

&#160;


Fannie Mae Mortgage pass-thru certificates

8.0
&#160;

&#160;


Ginnie Mae II Pool

6.2
&#160;

&#160;


Freddie Mac Gold Pool

5.2
&#160;

&#160;


Uniform Mortgage Backed Securities

4.3
&#160;

&#160;


Freddie Mac Multiclass Mortgage participation certificates

1.2
&#160;

&#160;


Petroleos Mexicanos

1.1
&#160;

&#160;


JPMorgan Chase &amp; Co

1.1
&#160;

&#160;


Goldman Sachs Group Inc/The

0.9
&#160;

&#160;


&#160;

67.4

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000069436_TH_0_Member"
      decimals="INF"
      id="ixv-257791"
      unitRef="pure">0.294</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000069436_TH_1_Member"
      decimals="INF"
      id="ixv-257792"
      unitRef="pure">0.100</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000069436_TH_2_Member"
      decimals="INF"
      id="ixv-257793"
      unitRef="pure">0.080</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000069436_TH_3_Member"
      decimals="INF"
      id="ixv-257794"
      unitRef="pure">0.062</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000069436_TH_4_Member"
      decimals="INF"
      id="ixv-257795"
      unitRef="pure">0.052</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000069436_TH_5_Member"
      decimals="INF"
      id="ixv-257796"
      unitRef="pure">0.043</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000069436_TH_6_Member"
      decimals="INF"
      id="ixv-257797"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-257798"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000069436_TH_8_Member"
      decimals="INF"
      id="ixv-257799"
      unitRef="pure">0.011</oef:PctOfNav>
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      decimals="INF"
      id="ixv-257800"
      unitRef="pure">0.009</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-1006">2024-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000088100_ClassMember" id="ixv-1018">Fidelity&#xae; Corporate Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000088100_ClassMember" id="ixv-1021">Fidelity Advisor&#xae; Corporate Bond Fund Class M</oef:ClassName>
    <dei:TradingSymbol contextRef="C000088100_ClassMember" id="ixv-1025">FCBTX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000088100_ClassMember" id="ixv-1045">This annual shareholder report contains information about Fidelity&#xae; Corporate Bond Fund for the period September 1, 2023 to August 31, 2024.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000088100_ClassMember" id="ixv-1047">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000088100_ClassMember" id="ixv-1052">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="C000088100_ClassMember" id="ixv-1054">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000088100_ClassMember" id="ixv-1057">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000088100_ClassMember" id="ixv-1060">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000088100_ClassMember" id="ixv-1067">&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 year?&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&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;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;FUND COST (PREVIOUS YEAR)&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:45%; 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:24%; 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:30%; 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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:45%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class M&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:24%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;86&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:30%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;0.82&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="C000088100_ClassMember"
      decimals="0"
      id="ixv-257801"
      unitRef="usd">86</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000088100_ClassMember"
      decimals="INF"
      id="ixv-257802"
      unitRef="pure">0.0082</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000088100_ClassMember" id="ixv-1111">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&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:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds posted a strong advance for the 12 months ending August 31, 2024, helped by a late-period gain, as the bond market reflected anticipated interest-rate reductions by the U.S. Federal Reserve, which are expected to start in September. The full 12-month period was marked by high volatility.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, security selection contributed to the fund's performance versus the benchmark for the fiscal year, while sector positioning had a roughly neutral impact overall.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Bond picks among issuers in the financials sector added the most value. Having greater-than-benchmark exposure to financials also helped.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Within financials, selection among banks contributed the most, followed by investment choices among insurance companies and overall positioning in real estate investment trusts.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Picks among industrial issuers also notably aided relative performance, as did a sizable underweight in the sector.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Within industrials, selection among consumer-focused companies led the way. Positioning among information technology issuers in the benchmark provided a further boost, along with picks in the energy category.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Holding of bonds issued by electric utility companies modestly contributed.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In terms of yield-curve positioning, the fund benefited from overweight exposure to the intermediate-maturity 5-10 year portion of the curve.&#160;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Outside of corporate credit, an allocation to U.S. Treasuries and cash - held for liquidity and risk-management purposes - meaningfully detracted. This negative was somewhat offset by underweighting other government-related categories, as these bonds lagged credit in an improving market environment.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000088100_ClassMember" id="ixv-1144">How did the Fund perform over the past 10 years?
&#160;
 &#160;&#160;
CUMULATIVE PERFORMANCE
August 31, 2014 through August 31, 2024.
Initial investment of $10,000&#160;and the current sales charge was paid.

Class M
&#160;

$9,600

$9,505
&#160;

$10,331
&#160;

$10,573
&#160;

$10,462
&#160;

$11,784
&#160;

$12,694
&#160;

$12,975
&#160;

$10,918
&#160;

$10,989
&#160;

$12,031
&#160;


Bloomberg U.S. Credit Bond Index
&#160;

$10,000

$9,957
&#160;

$10,868
&#160;

$11,074
&#160;

$10,965
&#160;

$12,389
&#160;

$13,269
&#160;

$13,569
&#160;

$11,611
&#160;

$11,709
&#160;

$12,761
&#160;


Bloomberg U.S. Aggregate Bond Index
&#160;

$10,000

$10,156
&#160;

$10,761
&#160;

$10,814
&#160;

$10,701
&#160;

$11,789
&#160;

$12,553
&#160;

$12,542
&#160;

$11,098
&#160;

$10,965
&#160;

$11,765
&#160;


&#160;

2014

2015

2016

2017

2018

2019

2020

2021

2022

2023

2024









</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000088100_LG_ClassMember_11YR" id="ixv-1165">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class M&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AcctVal
      contextRef="C000088100_ClassMember_AsOf_2014"
      decimals="0"
      id="ixv-257803"
      unitRef="usd">9600</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088100_ClassMember_AsOf_2015"
      decimals="0"
      id="ixv-257804"
      unitRef="usd">9505</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088100_ClassMember_AsOf_2016"
      decimals="0"
      id="ixv-257805"
      unitRef="usd">10331</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088100_ClassMember_AsOf_2017"
      decimals="0"
      id="ixv-257806"
      unitRef="usd">10573</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088100_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-257807"
      unitRef="usd">10462</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088100_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-257808"
      unitRef="usd">11784</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088100_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-257809"
      unitRef="usd">12694</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088100_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-257810"
      unitRef="usd">12975</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088100_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-257811"
      unitRef="usd">10918</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088100_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-257812"
      unitRef="usd">10989</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088100_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-257813"
      unitRef="usd">12031</oef:AcctVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000088100_LG_1_AdditionalIndexMember_11YR"
      id="ixv-1225">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Credit Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AcctVal
      contextRef="C000088100_1_AdditionalIndexMember_AsOf_2014"
      decimals="0"
      id="ixv-257814"
      unitRef="usd">10000</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088100_1_AdditionalIndexMember_AsOf_2015"
      decimals="0"
      id="ixv-257815"
      unitRef="usd">9957</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088100_1_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-257816"
      unitRef="usd">10868</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088100_1_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-257817"
      unitRef="usd">11074</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088100_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-257818"
      unitRef="usd">10965</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088100_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-257819"
      unitRef="usd">12389</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088100_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-257820"
      unitRef="usd">13269</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088100_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-257821"
      unitRef="usd">13569</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088100_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-257822"
      unitRef="usd">11611</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088100_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-257823"
      unitRef="usd">11709</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088100_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-257824"
      unitRef="usd">12761</oef:AcctVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000088100_LG_2_AdditionalIndexMember_11YR"
      id="ixv-1285">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AcctVal
      contextRef="C000088100_2_AdditionalIndexMember_AsOf_2014"
      decimals="0"
      id="ixv-257825"
      unitRef="usd">10000</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088100_2_AdditionalIndexMember_AsOf_2015"
      decimals="0"
      id="ixv-257826"
      unitRef="usd">10156</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088100_2_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-257827"
      unitRef="usd">10761</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088100_2_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-257828"
      unitRef="usd">10814</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088100_2_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-257829"
      unitRef="usd">10701</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088100_2_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-257830"
      unitRef="usd">11789</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088100_2_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-257831"
      unitRef="usd">12553</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088100_2_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-257832"
      unitRef="usd">12542</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088100_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-257833"
      unitRef="usd">11098</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088100_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-257834"
      unitRef="usd">10965</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088100_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-257835"
      unitRef="usd">11765</oef:AcctVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000088100_ClassMember" id="ixv-1394">AVERAGE ANNUAL TOTAL RETURNS:
&#160;
&#160;

1 Year

5 Year

10 Year


Class M (incl. 4.00% sales charge) &#160;

5.11%

-0.40%

1.87%


Class M (without 4.00% sales charge)

9.49%

0.42%

2.28%


Bloomberg U.S. Credit Bond Index

8.98%

0.59%

2.47%


Bloomberg U.S. Aggregate Bond Index

7.30%

-0.04%

1.64%




&#160;
Visit institutional.fidelity.com for more recent performance information.
&#160;


The Fund's past performance is not a good predictor of the Fund's future performance. &#160;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
&#160;



</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
      contextRef="C000088100_ClassMember_1YR"
      decimals="INF"
      id="ixv-257836"
      unitRef="pure">0.0511</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088100_ClassMember_5YR"
      decimals="INF"
      id="ixv-257837"
      unitRef="pure">-0.0040</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088100_ClassMember_10YR"
      decimals="INF"
      id="ixv-257838"
      unitRef="pure">0.0187</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088100_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-257839"
      unitRef="pure">0.0949</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088100_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-257840"
      unitRef="pure">0.0042</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088100_NoLoadClassMember_10YR"
      decimals="INF"
      id="ixv-257841"
      unitRef="pure">0.0228</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088100_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-257842"
      unitRef="pure">0.0898</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088100_0_AdditionalIndexMember_5YR"
      decimals="INF"
      id="ixv-257843"
      unitRef="pure">0.0059</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088100_0_AdditionalIndexMember_10YR"
      decimals="INF"
      id="ixv-257844"
      unitRef="pure">0.0247</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088100_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-257845"
      unitRef="pure">0.0730</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088100_1_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-257846"
      unitRef="pure">-0.0004</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088100_1_BBIndexMember_10YR"
      decimals="INF"
      id="ixv-257847"
      unitRef="pure">0.0164</oef:AvgAnnlRtrPct>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000088100_ClassMember" id="ixv-1483">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span&gt;</oef:PerformancePastDoesNotIndicateFuture>
    <oef:NoDeductionOfTaxesTextBlock contextRef="C000088100_ClassMember" id="ixv-1487">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.&lt;/span&gt;</oef:NoDeductionOfTaxesTextBlock>
    <oef:AddlFundStatisticsTextBlock contextRef="C000088100_ClassMember" id="ixv-1494">&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 August 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;/div&gt;
&lt;span style="line-height:11px;"&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:bold;"&gt; &lt;span&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/div&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;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;$&lt;/span&gt;2,001,136,363&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;621&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;6,038,514&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="middle"&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="C000088100_InstantMember"
      decimals="0"
      id="ixv-257848"
      unitRef="usd">2001136363</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000088100_InstantMember"
      decimals="INF"
      id="ixv-257849"
      unitRef="holding">621</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000088100_ClassMember"
      decimals="0"
      id="ixv-257850"
      unitRef="usd">6038514</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000088100_ClassMember"
      decimals="INF"
      id="ixv-257851"
      unitRef="pure">0.30</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000088100_ClassMember" id="ixv-1575">
&#160;

U.S. Government and U.S. Government Agency Obligations

9.8


AAA

0.1


AA

0.0


A

17.0


BBB

60.7


BB

6.5


B

0.7


Not Rated

0.2


Short-Term Investments and Net Other Assets (Liabilities)

5.0




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;
&#160;

Corporate Bonds

84.4


U.S. Treasury Obligations

9.8


Asset-Backed Securities

0.3


Preferred Securities

0.3


Foreign Government and Government Agency Obligations

0.1


Other Investments

0.1


Municipal Securities

0.0


Short-Term Investments and Net Other Assets (Liabilities)

5.0




ASSET ALLOCATION (% of Fund's net assets)


&#160;








United States

79.9


United Kingdom

4.0


Canada

3.3


Ireland

2.6


France

2.1


Germany

1.9


Switzerland

1.4


Netherlands

1.1


Spain

0.9


Others

2.8




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;


&#160;







</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-257852"
      unitRef="pure">0.098</oef:PctOfNav>
    <oef:PctOfNav
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    <oef:PctOfNav
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    <oef:PctOfNav
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      id="ixv-257861"
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    <oef:PctOfNav
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      id="ixv-257862"
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    <oef:PctOfNav
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    <oef:PctOfNav
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      id="ixv-257864"
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      decimals="INF"
      id="ixv-257865"
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    <oef:PctOfNav
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      decimals="INF"
      id="ixv-257866"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088100_AA_MunicipalSecurities_Member"
      decimals="INF"
      id="ixv-257867"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088100_AA_ShortTermInvestmentsandNetOtherAssetsLiabilities_Member"
      decimals="INF"
      id="ixv-257868"
      unitRef="pure">0.050</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088100_GD_US_Member"
      decimals="INF"
      id="ixv-257869"
      unitRef="pure">0.799</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-257870"
      unitRef="pure">0.040</oef:PctOfNav>
    <oef:PctOfNav
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      id="ixv-257871"
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    <oef:PctOfNav
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    <oef:PctOfNav
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    <oef:PctOfNav
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      id="ixv-257874"
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    <oef:PctOfNav
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      decimals="INF"
      id="ixv-257875"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088100_GD_NL_Member"
      decimals="INF"
      id="ixv-257876"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-257877"
      unitRef="pure">0.009</oef:PctOfNav>
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    <oef:LargestHoldingsTableTextBlock contextRef="C000088100_ClassMember" id="ixv-1815">
TOP HOLDINGS
(% of Fund's net assets)

&#160;

&#160;


US Treasury Bonds

9.5
&#160;

&#160;


Bank of America Corp

2.1
&#160;

&#160;


JPMorgan Chase &amp; Co

1.9
&#160;

&#160;


Boeing Co

1.5
&#160;

&#160;


UBS Group AG

1.4
&#160;

&#160;


AerCap Ireland Capital DAC / AerCap Global Aviation Trust

1.1
&#160;

&#160;


Wells Fargo &amp; Co

1.1
&#160;

&#160;


Duke Energy Corp

1.1
&#160;

&#160;


HSBC Holdings PLC

1.1
&#160;

&#160;


CVS Health Corp

1.1
&#160;

&#160;


&#160;

21.9

&#160;



</oef:LargestHoldingsTableTextBlock>
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      id="ixv-257879"
      unitRef="pure">0.095</oef:PctOfNav>
    <oef:PctOfNav
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      id="ixv-257880"
      unitRef="pure">0.021</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088100_TH_2_Member"
      decimals="INF"
      id="ixv-257881"
      unitRef="pure">0.019</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-257882"
      unitRef="pure">0.015</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088100_TH_4_Member"
      decimals="INF"
      id="ixv-257883"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088100_TH_5_Member"
      decimals="INF"
      id="ixv-257884"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088100_TH_6_Member"
      decimals="INF"
      id="ixv-257885"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088100_TH_7_Member"
      decimals="INF"
      id="ixv-257886"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088100_TH_8_Member"
      decimals="INF"
      id="ixv-257887"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088100_TH_9_Member"
      decimals="INF"
      id="ixv-257888"
      unitRef="pure">0.011</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-1997">2024-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000088096_ClassMember" id="ixv-2009">Fidelity&#xae; Corporate Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000088096_ClassMember" id="ixv-2012">Fidelity&#xae; Corporate Bond Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000088096_ClassMember" id="ixv-2016">FCBFX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000088096_ClassMember" id="ixv-2036">This annual shareholder report contains information about Fidelity&#xae; Corporate Bond Fund for the period September 1, 2023 to August 31, 2024.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000088096_ClassMember" id="ixv-2038">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000088096_ClassMember" id="ixv-2043">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="C000088096_ClassMember" id="ixv-2045">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000088096_ClassMember" id="ixv-2048">1-800-544-8544</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000088096_ClassMember" id="ixv-2051">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000088096_ClassMember" id="ixv-2058">&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 year?&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&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;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;FUND COST (PREVIOUS YEAR)&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:45%; 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:24%; 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:30%; 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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:45%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Corporate Bond Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:24%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;47&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:30%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;0.45&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="C000088096_ClassMember"
      decimals="0"
      id="ixv-257889"
      unitRef="usd">47</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000088096_ClassMember"
      decimals="INF"
      id="ixv-257890"
      unitRef="pure">0.0045</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000088096_ClassMember" id="ixv-2102">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&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:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds posted a strong advance for the 12 months ending August 31, 2024, helped by a late-period gain, as the bond market reflected anticipated interest-rate reductions by the U.S. Federal Reserve, which are expected to start in September. The full 12-month period was marked by high volatility.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, security selection contributed to the fund's performance versus the benchmark for the fiscal year, while sector positioning had a roughly neutral impact overall.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Bond picks among issuers in the financials sector added the most value. Having greater-than-benchmark exposure to financials also helped.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Within financials, selection among banks contributed the most, followed by investment choices among insurance companies and overall positioning in real estate investment trusts.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Picks among industrial issuers also notably aided relative performance, as did a sizable underweight in the sector.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Within industrials, selection among consumer-focused companies led the way. Positioning among information technology issuers in the benchmark provided a further boost, along with picks in the energy category.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Holding of bonds issued by electric utility companies modestly contributed.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In terms of yield-curve positioning, the fund benefited from overweight exposure to the intermediate-maturity 5-10 year portion of the curve.&#160;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Outside of corporate credit, an allocation to U.S. Treasuries and cash - held for liquidity and risk-management purposes - meaningfully detracted. This negative was somewhat offset by underweighting other government-related categories, as these bonds lagged credit in an improving market environment.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000088096_ClassMember" id="ixv-2135">How did the Fund perform over the past 10 years?
&#160;
 &#160;&#160;
CUMULATIVE PERFORMANCE
August 31, 2014 through August 31, 2024.
Initial investment of $10,000.

Fidelity&#xae; Corporate Bond Fund
&#160;

$10,000

$9,942
&#160;

$10,850
&#160;

$11,151
&#160;

$11,080
&#160;

$12,532
&#160;

$13,550
&#160;

$13,897
&#160;

$11,737
&#160;

$11,858
&#160;

$13,031
&#160;


Bloomberg U.S. Credit Bond Index
&#160;

$10,000

$9,957
&#160;

$10,868
&#160;

$11,074
&#160;

$10,965
&#160;

$12,389
&#160;

$13,269
&#160;

$13,569
&#160;

$11,611
&#160;

$11,709
&#160;

$12,761
&#160;


Bloomberg U.S. Aggregate Bond Index
&#160;

$10,000

$10,156
&#160;

$10,761
&#160;

$10,814
&#160;

$10,701
&#160;

$11,789
&#160;

$12,553
&#160;

$12,542
&#160;

$11,098
&#160;

$10,965
&#160;

$11,765
&#160;


&#160;

2014

2015

2016

2017

2018

2019

2020

2021

2022

2023

2024









</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000088096_LG_ClassMember_11YR" id="ixv-2154">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Corporate Bond Fund&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AcctVal
      contextRef="C000088096_ClassMember_AsOf_2014"
      decimals="0"
      id="ixv-257891"
      unitRef="usd">10000</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088096_ClassMember_AsOf_2015"
      decimals="0"
      id="ixv-257892"
      unitRef="usd">9942</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088096_ClassMember_AsOf_2016"
      decimals="0"
      id="ixv-257893"
      unitRef="usd">10850</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088096_ClassMember_AsOf_2017"
      decimals="0"
      id="ixv-257894"
      unitRef="usd">11151</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088096_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-257895"
      unitRef="usd">11080</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088096_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-257896"
      unitRef="usd">12532</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088096_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-257897"
      unitRef="usd">13550</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088096_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-257898"
      unitRef="usd">13897</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088096_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-257899"
      unitRef="usd">11737</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088096_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-257900"
      unitRef="usd">11858</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088096_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-257901"
      unitRef="usd">13031</oef:AcctVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000088096_LG_1_AdditionalIndexMember_11YR"
      id="ixv-2214">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Credit Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AcctVal
      contextRef="C000088096_1_AdditionalIndexMember_AsOf_2014"
      decimals="0"
      id="ixv-257902"
      unitRef="usd">10000</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088096_1_AdditionalIndexMember_AsOf_2015"
      decimals="0"
      id="ixv-257903"
      unitRef="usd">9957</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088096_1_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-257904"
      unitRef="usd">10868</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088096_1_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-257905"
      unitRef="usd">11074</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088096_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-257906"
      unitRef="usd">10965</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088096_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-257907"
      unitRef="usd">12389</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088096_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-257908"
      unitRef="usd">13269</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088096_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-257909"
      unitRef="usd">13569</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088096_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-257910"
      unitRef="usd">11611</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088096_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-257911"
      unitRef="usd">11709</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088096_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-257912"
      unitRef="usd">12761</oef:AcctVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000088096_LG_2_AdditionalIndexMember_11YR"
      id="ixv-2274">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AcctVal
      contextRef="C000088096_2_AdditionalIndexMember_AsOf_2014"
      decimals="0"
      id="ixv-257913"
      unitRef="usd">10000</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088096_2_AdditionalIndexMember_AsOf_2015"
      decimals="0"
      id="ixv-257914"
      unitRef="usd">10156</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088096_2_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-257915"
      unitRef="usd">10761</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088096_2_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-257916"
      unitRef="usd">10814</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088096_2_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-257917"
      unitRef="usd">10701</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088096_2_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-257918"
      unitRef="usd">11789</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088096_2_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-257919"
      unitRef="usd">12553</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088096_2_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-257920"
      unitRef="usd">12542</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088096_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-257921"
      unitRef="usd">11098</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088096_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-257922"
      unitRef="usd">10965</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088096_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-257923"
      unitRef="usd">11765</oef:AcctVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000088096_ClassMember" id="ixv-2383">AVERAGE ANNUAL TOTAL RETURNS:
&#160;
&#160;

1 Year

5 Year

10 Year


Fidelity&#xae; Corporate Bond Fund

9.89%

0.78%

2.68%


Bloomberg U.S. Credit Bond Index

8.98%

0.59%

2.47%


Bloomberg U.S. Aggregate Bond Index

7.30%

-0.04%

1.64%




&#160;
Visit www.fidelity.com for more recent performance information.
&#160;


The Fund's past performance is not a good predictor of the Fund's future performance. &#160;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
&#160;



</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
      contextRef="C000088096_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-257924"
      unitRef="pure">0.0989</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088096_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-257925"
      unitRef="pure">0.0078</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088096_NoLoadClassMember_10YR"
      decimals="INF"
      id="ixv-257926"
      unitRef="pure">0.0268</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088096_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-257927"
      unitRef="pure">0.0898</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088096_0_AdditionalIndexMember_5YR"
      decimals="INF"
      id="ixv-257928"
      unitRef="pure">0.0059</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088096_0_AdditionalIndexMember_10YR"
      decimals="INF"
      id="ixv-257929"
      unitRef="pure">0.0247</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088096_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-257930"
      unitRef="pure">0.0730</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088096_1_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-257931"
      unitRef="pure">-0.0004</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088096_1_BBIndexMember_10YR"
      decimals="INF"
      id="ixv-257932"
      unitRef="pure">0.0164</oef:AvgAnnlRtrPct>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000088096_ClassMember" id="ixv-2457">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span&gt;</oef:PerformancePastDoesNotIndicateFuture>
    <oef:NoDeductionOfTaxesTextBlock contextRef="C000088096_ClassMember" id="ixv-2461">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.&lt;/span&gt;</oef:NoDeductionOfTaxesTextBlock>
    <oef:AddlFundStatisticsTextBlock contextRef="C000088096_ClassMember" id="ixv-2468">&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 August 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;/div&gt;
&lt;span style="line-height:11px;"&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:bold;"&gt; &lt;span&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/div&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;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;$&lt;/span&gt;2,001,136,363&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;621&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;6,038,514&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="middle"&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="C000088096_InstantMember"
      decimals="0"
      id="ixv-257933"
      unitRef="usd">2001136363</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000088096_InstantMember"
      decimals="INF"
      id="ixv-257934"
      unitRef="holding">621</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000088096_ClassMember"
      decimals="0"
      id="ixv-257935"
      unitRef="usd">6038514</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000088096_ClassMember"
      decimals="INF"
      id="ixv-257936"
      unitRef="pure">0.30</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000088096_ClassMember" id="ixv-2549">
&#160;

U.S. Government and U.S. Government Agency Obligations

9.8


AAA

0.1


AA

0.0


A

17.0


BBB

60.7


BB

6.5


B

0.7


Not Rated

0.2


Short-Term Investments and Net Other Assets (Liabilities)

5.0




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;
&#160;

Corporate Bonds

84.4


U.S. Treasury Obligations

9.8


Asset-Backed Securities

0.3


Preferred Securities

0.3


Foreign Government and Government Agency Obligations

0.1


Other Investments

0.1


Municipal Securities

0.0


Short-Term Investments and Net Other Assets (Liabilities)

5.0




ASSET ALLOCATION (% of Fund's net assets)


&#160;








United States

79.9


United Kingdom

4.0


Canada

3.3


Ireland

2.6


France

2.1


Germany

1.9


Switzerland

1.4


Netherlands

1.1


Spain

0.9


Others

2.8




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;


&#160;







</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000088096_QD_USGovernmentandUSGovernmentAgencyObligations_Member"
      decimals="INF"
      id="ixv-257937"
      unitRef="pure">0.098</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088096_QD_AAA_Member"
      decimals="INF"
      id="ixv-257938"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-257939"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088096_QD_A_Member"
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      id="ixv-257940"
      unitRef="pure">0.170</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-257941"
      unitRef="pure">0.607</oef:PctOfNav>
    <oef:PctOfNav
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      id="ixv-257942"
      unitRef="pure">0.065</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088096_QD_B_Member"
      decimals="INF"
      id="ixv-257943"
      unitRef="pure">0.007</oef:PctOfNav>
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      id="ixv-257944"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-257945"
      unitRef="pure">0.050</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088096_AA_CorporateBonds_Member"
      decimals="INF"
      id="ixv-257946"
      unitRef="pure">0.844</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088096_AA_USTreasuryObligations_Member"
      decimals="INF"
      id="ixv-257947"
      unitRef="pure">0.098</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-257948"
      unitRef="pure">0.003</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088096_AA_PreferredSecurities_Member"
      decimals="INF"
      id="ixv-257949"
      unitRef="pure">0.003</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088096_AA_ForeignGovernmentandGovernmentAgencyObligations_Member"
      decimals="INF"
      id="ixv-257950"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088096_AA_OtherInvestments_Member"
      decimals="INF"
      id="ixv-257951"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088096_AA_MunicipalSecurities_Member"
      decimals="INF"
      id="ixv-257952"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088096_AA_ShortTermInvestmentsandNetOtherAssetsLiabilities_Member"
      decimals="INF"
      id="ixv-257953"
      unitRef="pure">0.050</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088096_GD_US_Member"
      decimals="INF"
      id="ixv-257954"
      unitRef="pure">0.799</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088096_GD_GB_Member"
      decimals="INF"
      id="ixv-257955"
      unitRef="pure">0.040</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088096_GD_CA_Member"
      decimals="INF"
      id="ixv-257956"
      unitRef="pure">0.033</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088096_GD_IE_Member"
      decimals="INF"
      id="ixv-257957"
      unitRef="pure">0.026</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088096_GD_FR_Member"
      decimals="INF"
      id="ixv-257958"
      unitRef="pure">0.021</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088096_GD_DE_Member"
      decimals="INF"
      id="ixv-257959"
      unitRef="pure">0.019</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088096_GD_CH_Member"
      decimals="INF"
      id="ixv-257960"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088096_GD_NL_Member"
      decimals="INF"
      id="ixv-257961"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088096_GD_ES_Member"
      decimals="INF"
      id="ixv-257962"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088096_GD_Other_Member"
      decimals="INF"
      id="ixv-257963"
      unitRef="pure">0.028</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000088096_ClassMember" id="ixv-2789">
TOP HOLDINGS
(% of Fund's net assets)

&#160;

&#160;


US Treasury Bonds

9.5
&#160;

&#160;


Bank of America Corp

2.1
&#160;

&#160;


JPMorgan Chase &amp; Co

1.9
&#160;

&#160;


Boeing Co

1.5
&#160;

&#160;


UBS Group AG

1.4
&#160;

&#160;


AerCap Ireland Capital DAC / AerCap Global Aviation Trust

1.1
&#160;

&#160;


Wells Fargo &amp; Co

1.1
&#160;

&#160;


Duke Energy Corp

1.1
&#160;

&#160;


HSBC Holdings PLC

1.1
&#160;

&#160;


CVS Health Corp

1.1
&#160;

&#160;


&#160;

21.9

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000088096_TH_0_Member"
      decimals="INF"
      id="ixv-257964"
      unitRef="pure">0.095</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088096_TH_1_Member"
      decimals="INF"
      id="ixv-257965"
      unitRef="pure">0.021</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088096_TH_2_Member"
      decimals="INF"
      id="ixv-257966"
      unitRef="pure">0.019</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088096_TH_3_Member"
      decimals="INF"
      id="ixv-257967"
      unitRef="pure">0.015</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088096_TH_4_Member"
      decimals="INF"
      id="ixv-257968"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088096_TH_5_Member"
      decimals="INF"
      id="ixv-257969"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088096_TH_6_Member"
      decimals="INF"
      id="ixv-257970"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088096_TH_7_Member"
      decimals="INF"
      id="ixv-257971"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088096_TH_8_Member"
      decimals="INF"
      id="ixv-257972"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088096_TH_9_Member"
      decimals="INF"
      id="ixv-257973"
      unitRef="pure">0.011</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-2971">2024-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000153158_ClassMember" id="ixv-2983">Fidelity&#xae; Series Short-Term Credit Fund</oef:FundName>
    <oef:ClassName contextRef="C000153158_ClassMember" id="ixv-2986">Fidelity&#xae; Series Short-Term Credit Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000153158_ClassMember" id="ixv-2990">FYBTX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000153158_ClassMember" id="ixv-3010">This annual shareholder report contains information about Fidelity&#xae; Series Short-Term Credit Fund for the period September 1, 2023 to August 31, 2024.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000153158_ClassMember" id="ixv-3012">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000153158_ClassMember" id="ixv-3017">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="C000153158_ClassMember" id="ixv-3019">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000153158_ClassMember" id="ixv-3022">1-800-544-8544</oef:AddlInfoPhoneNumber>
    <oef:ExpensesTextBlock contextRef="C000153158_ClassMember" id="ixv-3029">&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 year?&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&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;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;FUND COST (PREVIOUS YEAR)&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:45%; 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:24%; 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:30%; 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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:45%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Series Short-Term Credit Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:24%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &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:30%; 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>
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      id="ixv-257974"
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    <oef:ExpenseRatioPct
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      decimals="INF"
      id="ixv-257975"
      unitRef="pure">0.0000</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000153158_ClassMember" id="ixv-3082">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&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:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds posted a strong advance for the 12 months ending August 31, 2024, helped by a late-period gain, as the bond market reflected anticipated interest-rate reductions by the U.S. Federal Reserve, which are expected to start in September. The full 12-month period was marked by high volatility.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, security selection and, to a lesser extent, sector allocation each contributed to performance versus the benchmark.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;The fund's non-benchmark exposure to asset-backed securities, including car loan debt and collateralized loan obligations, meaningfully contributed. An out-of-benchmark allocation to commercial mortgage-backed securities helped as well.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In contrast, the fund's yield-curve positioning detracted from relative performance.&#160;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;At period end, corporate credit holdings made up 71% of fund assets, down from roughly 76% a year ago and underweight versus the benchmark average of 82%. Out-of-benchmark exposure to asset-backed securities stood at roughly 17% as of August 31, while U.S. Treasurys composed about 6% of the portfolio.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000153158_ClassMember" id="ixv-3103">How did the Fund perform over the life of Fund?
&#160;
 &#160;&#160;
CUMULATIVE PERFORMANCE
March 27, 2015 through August 31, 2024.
Initial investment of $10,000.

Fidelity&#xae; Series Short-Term Credit Fund
&#160;

$10,000

$10,001
&#160;

$10,199
&#160;

$10,320
&#160;

$10,405
&#160;

$10,927
&#160;

$11,402
&#160;

$11,511
&#160;

$11,082
&#160;

$11,419
&#160;


Bloomberg U.S. Credit 1-3 Years Bond Index
&#160;

$10,000

$10,013
&#160;

$10,251
&#160;

$10,414
&#160;

$10,476
&#160;

$11,009
&#160;

$11,451
&#160;

$11,558
&#160;

$11,112
&#160;

$11,359
&#160;


Bloomberg U.S. Aggregate Bond Index
&#160;

$10,000

$9,897
&#160;

$10,488
&#160;

$10,539
&#160;

$10,429
&#160;

$11,490
&#160;

$12,233
&#160;

$12,223
&#160;

$10,816
&#160;

$10,686
&#160;


&#160;

2015

2016

2017

2018

2019

2020

2021

2022

2023

2024









</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000153158_LG_ClassMember_10YR" id="ixv-3122">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Series Short-Term Credit Fund&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AcctVal
      contextRef="C000153158_ClassMember_AsOf_2015"
      decimals="0"
      id="ixv-257976"
      unitRef="usd">10000</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000153158_ClassMember_AsOf_2016"
      decimals="0"
      id="ixv-257977"
      unitRef="usd">10001</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000153158_ClassMember_AsOf_2017"
      decimals="0"
      id="ixv-257978"
      unitRef="usd">10199</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000153158_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-257979"
      unitRef="usd">10320</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000153158_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-257980"
      unitRef="usd">10405</oef:AcctVal>
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      contextRef="C000153158_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-257981"
      unitRef="usd">10927</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000153158_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-257982"
      unitRef="usd">11402</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000153158_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-257983"
      unitRef="usd">11511</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000153158_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-257984"
      unitRef="usd">11082</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000153158_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-257985"
      unitRef="usd">11419</oef:AcctVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000153158_LG_1_AdditionalIndexMember_10YR"
      id="ixv-3177">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Credit 1-3 Years Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AcctVal
      contextRef="C000153158_1_AdditionalIndexMember_AsOf_2015"
      decimals="0"
      id="ixv-257986"
      unitRef="usd">10000</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000153158_1_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-257987"
      unitRef="usd">10013</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000153158_1_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-257988"
      unitRef="usd">10251</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000153158_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-257989"
      unitRef="usd">10414</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000153158_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-257990"
      unitRef="usd">10476</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000153158_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-257991"
      unitRef="usd">11009</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000153158_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-257992"
      unitRef="usd">11451</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000153158_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-257993"
      unitRef="usd">11558</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000153158_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-257994"
      unitRef="usd">11112</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000153158_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-257995"
      unitRef="usd">11359</oef:AcctVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000153158_LG_2_AdditionalIndexMember_10YR"
      id="ixv-3232">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AcctVal
      contextRef="C000153158_2_AdditionalIndexMember_AsOf_2015"
      decimals="0"
      id="ixv-257996"
      unitRef="usd">10000</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000153158_2_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-257997"
      unitRef="usd">9897</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000153158_2_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-257998"
      unitRef="usd">10488</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000153158_2_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-257999"
      unitRef="usd">10539</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000153158_2_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-258000"
      unitRef="usd">10429</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000153158_2_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-258001"
      unitRef="usd">11490</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000153158_2_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-258002"
      unitRef="usd">12233</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000153158_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-258003"
      unitRef="usd">12223</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000153158_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-258004"
      unitRef="usd">10816</oef:AcctVal>
    <oef:AcctVal
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      decimals="0"
      id="ixv-258005"
      unitRef="usd">10686</oef:AcctVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000153158_ClassMember" id="ixv-3333">AVERAGE ANNUAL TOTAL RETURNS:
&#160;
&#160;

1 Year

5 Year

Life of Fund&#160;A


Fidelity&#xae; Series Short-Term Credit Fund

7.40%

2.33%

2.19%


Bloomberg U.S. Credit 1-3 Years Bond Index

7.04%

2.01%

2.09%


Bloomberg U.S. Aggregate Bond Index

7.30%

-0.04%

1.46%




A&#160; &#160;From March 27, 2015
&#160;
Visit www.fidelity.com for more recent performance information.
&#160;


The Fund's past performance is not a good predictor of the Fund's future performance. &#160;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
&#160;



</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
      contextRef="C000153158_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-258006"
      unitRef="pure">0.0740</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000153158_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-258007"
      unitRef="pure">0.0233</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000153158_NoLoadClassMember_2023-09-01_2024-08-31"
      decimals="INF"
      id="ixv-258008"
      unitRef="pure">0.0219</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000153158_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-258009"
      unitRef="pure">0.0704</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000153158_0_AdditionalIndexMember_5YR"
      decimals="INF"
      id="ixv-258010"
      unitRef="pure">0.0201</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000153158_0_AdditionalIndexMember_LOC"
      decimals="INF"
      id="ixv-258011"
      unitRef="pure">0.0209</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000153158_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-258012"
      unitRef="pure">0.0730</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000153158_1_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-258013"
      unitRef="pure">-0.0004</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000153158_1_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-258014"
      unitRef="pure">0.0146</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate contextRef="C000153158_ClassMember" id="ixv-3400">2015-03-27</oef:PerfInceptionDate>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000153158_ClassMember" id="ixv-3417">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span&gt;</oef:PerformancePastDoesNotIndicateFuture>
    <oef:NoDeductionOfTaxesTextBlock contextRef="C000153158_ClassMember" id="ixv-3421">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.&lt;/span&gt;</oef:NoDeductionOfTaxesTextBlock>
    <oef:AddlFundStatisticsTextBlock contextRef="C000153158_ClassMember" id="ixv-3428">&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 August 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;/div&gt;
&lt;span style="line-height:11px;"&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:bold;"&gt; &lt;span&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/div&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;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;$&lt;/span&gt;480,107,974&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;401&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;0&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="middle"&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;72&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
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      id="ixv-258015"
      unitRef="usd">480107974</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000153158_InstantMember"
      decimals="INF"
      id="ixv-258016"
      unitRef="holding">401</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000153158_ClassMember"
      decimals="0"
      id="ixv-258017"
      unitRef="usd">0</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000153158_ClassMember"
      decimals="INF"
      id="ixv-258018"
      unitRef="pure">0.72</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000153158_ClassMember" id="ixv-3509">
&#160;

U.S. Government and U.S. Government Agency Obligations

7.2


AAA

16.2


AA

2.8


A

32.3


BBB

36.0


BB

1.9


B

0.0


Not Rated

2.9


Short-Term Investments and Net Other Assets (Liabilities)

0.7




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;
&#160;

Corporate Bonds

69.6


Asset-Backed Securities

16.0


U.S. Treasury Obligations

6.3


CMOs and Other Mortgage Related Securities

5.3


Other Investments

1.2


U.S. Government Agency - Mortgage Securities

0.9


Short-Term Investments and Net Other Assets (Liabilities)

0.7




ASSET ALLOCATION (% of Fund's net assets)


&#160;








United States

75.9


United Kingdom

5.4


Germany

5.4


Grand Cayman (Uk Overseas Ter)

3.6


Canada

2.5


Japan

2.0


Ireland

1.6


Netherlands

0.6


Switzerland

0.5


Others

2.5




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;


&#160;







</oef:HoldingsTableTextBlock>
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      id="ixv-258020"
      unitRef="pure">0.162</oef:PctOfNav>
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      unitRef="pure">0.028</oef:PctOfNav>
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      unitRef="pure">0.160</oef:PctOfNav>
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      id="ixv-258030"
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      id="ixv-258031"
      unitRef="pure">0.053</oef:PctOfNav>
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      decimals="INF"
      id="ixv-258032"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-258033"
      unitRef="pure">0.009</oef:PctOfNav>
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      decimals="INF"
      id="ixv-258034"
      unitRef="pure">0.007</oef:PctOfNav>
    <oef:PctOfNav
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      id="ixv-258035"
      unitRef="pure">0.759</oef:PctOfNav>
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      decimals="INF"
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      unitRef="pure">0.054</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-258037"
      unitRef="pure">0.054</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000153158_GD_GrandCaymanUkOverseasTer_Member"
      decimals="INF"
      id="ixv-258038"
      unitRef="pure">0.036</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000153158_GD_CA_Member"
      decimals="INF"
      id="ixv-258039"
      unitRef="pure">0.025</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000153158_GD_JP_Member"
      decimals="INF"
      id="ixv-258040"
      unitRef="pure">0.020</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000153158_GD_IE_Member"
      decimals="INF"
      id="ixv-258041"
      unitRef="pure">0.016</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000153158_GD_NL_Member"
      decimals="INF"
      id="ixv-258042"
      unitRef="pure">0.006</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000153158_GD_CH_Member"
      decimals="INF"
      id="ixv-258043"
      unitRef="pure">0.005</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000153158_GD_Other_Member"
      decimals="INF"
      id="ixv-258044"
      unitRef="pure">0.025</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000153158_ClassMember" id="ixv-3743">
TOP HOLDINGS
(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

6.3
&#160;

&#160;


JPMorgan Chase &amp; Co

3.1
&#160;

&#160;


Bank of America Corp

2.8
&#160;

&#160;


Wells Fargo &amp; Co

2.3
&#160;

&#160;


HSBC Holdings PLC

2.1
&#160;

&#160;


General Motors Financial Co Inc

2.1
&#160;

&#160;


T-Mobile USA Inc

1.8
&#160;

&#160;


Hyundai Capital America

1.6
&#160;

&#160;


Cf Hippolyta Issuer LLC

1.6
&#160;

&#160;


AerCap Ireland Capital DAC / AerCap Global Aviation Trust

1.4
&#160;

&#160;


&#160;

25.1

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000153158_TH_0_Member"
      decimals="INF"
      id="ixv-258045"
      unitRef="pure">0.063</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000153158_TH_1_Member"
      decimals="INF"
      id="ixv-258046"
      unitRef="pure">0.031</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000153158_TH_2_Member"
      decimals="INF"
      id="ixv-258047"
      unitRef="pure">0.028</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000153158_TH_3_Member"
      decimals="INF"
      id="ixv-258048"
      unitRef="pure">0.023</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000153158_TH_4_Member"
      decimals="INF"
      id="ixv-258049"
      unitRef="pure">0.021</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000153158_TH_5_Member"
      decimals="INF"
      id="ixv-258050"
      unitRef="pure">0.021</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000153158_TH_6_Member"
      decimals="INF"
      id="ixv-258051"
      unitRef="pure">0.018</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000153158_TH_7_Member"
      decimals="INF"
      id="ixv-258052"
      unitRef="pure">0.016</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000153158_TH_8_Member"
      decimals="INF"
      id="ixv-258053"
      unitRef="pure">0.016</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000153158_TH_9_Member"
      decimals="INF"
      id="ixv-258054"
      unitRef="pure">0.014</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-3925">2024-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000088097_ClassMember" id="ixv-3937">Fidelity&#xae; Corporate Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000088097_ClassMember" id="ixv-3940">Fidelity Advisor&#xae; Corporate Bond Fund Class A</oef:ClassName>
    <dei:TradingSymbol contextRef="C000088097_ClassMember" id="ixv-3944">FCBAX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000088097_ClassMember" id="ixv-3964">This annual shareholder report contains information about Fidelity&#xae; Corporate Bond Fund for the period September 1, 2023 to August 31, 2024.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000088097_ClassMember" id="ixv-3966">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000088097_ClassMember" id="ixv-3971">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="C000088097_ClassMember" id="ixv-3973">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000088097_ClassMember" id="ixv-3976">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000088097_ClassMember" id="ixv-3979">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000088097_ClassMember" id="ixv-3986">&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 year?&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&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;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;FUND COST (PREVIOUS YEAR)&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:45%; 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:24%; 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:30%; 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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:45%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class A&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:24%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;81&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:30%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;0.77&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="C000088097_ClassMember"
      decimals="0"
      id="ixv-258055"
      unitRef="usd">81</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000088097_ClassMember"
      decimals="INF"
      id="ixv-258056"
      unitRef="pure">0.0077</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000088097_ClassMember" id="ixv-4030">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&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:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds posted a strong advance for the 12 months ending August 31, 2024, helped by a late-period gain, as the bond market reflected anticipated interest-rate reductions by the U.S. Federal Reserve, which are expected to start in September. The full 12-month period was marked by high volatility.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, security selection contributed to the fund's performance versus the benchmark for the fiscal year, while sector positioning had a roughly neutral impact overall.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Bond picks among issuers in the financials sector added the most value. Having greater-than-benchmark exposure to financials also helped.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Within financials, selection among banks contributed the most, followed by investment choices among insurance companies and overall positioning in real estate investment trusts.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Picks among industrial issuers also notably aided relative performance, as did a sizable underweight in the sector.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Within industrials, selection among consumer-focused companies led the way. Positioning among information technology issuers in the benchmark provided a further boost, along with picks in the energy category.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Holding of bonds issued by electric utility companies modestly contributed.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In terms of yield-curve positioning, the fund benefited from overweight exposure to the intermediate-maturity 5-10 year portion of the curve.&#160;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Outside of corporate credit, an allocation to U.S. Treasuries and cash - held for liquidity and risk-management purposes - meaningfully detracted. This negative was somewhat offset by underweighting other government-related categories, as these bonds lagged credit in an improving market environment.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000088097_ClassMember" id="ixv-4063">How did the Fund perform over the past 10 years?
&#160;
 &#160;&#160;
CUMULATIVE PERFORMANCE
August 31, 2014 through August 31, 2024.
Initial investment of $10,000&#160;and the current sales charge was paid.

Class A
&#160;

$9,600

$9,512
&#160;

$10,346
&#160;

$10,597
&#160;

$10,494
&#160;

$11,830
&#160;

$12,750
&#160;

$13,036
&#160;

$10,975
&#160;

$11,051
&#160;

$12,106
&#160;


Bloomberg U.S. Credit Bond Index
&#160;

$10,000

$9,957
&#160;

$10,868
&#160;

$11,074
&#160;

$10,965
&#160;

$12,389
&#160;

$13,269
&#160;

$13,569
&#160;

$11,611
&#160;

$11,709
&#160;

$12,761
&#160;


Bloomberg U.S. Aggregate Bond Index
&#160;

$10,000

$10,156
&#160;

$10,761
&#160;

$10,814
&#160;

$10,701
&#160;

$11,789
&#160;

$12,553
&#160;

$12,542
&#160;

$11,098
&#160;

$10,965
&#160;

$11,765
&#160;


&#160;

2014

2015

2016

2017

2018

2019

2020

2021

2022

2023

2024









</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000088097_LG_ClassMember_11YR" id="ixv-4084">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class A&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AcctVal
      contextRef="C000088097_ClassMember_AsOf_2014"
      decimals="0"
      id="ixv-258057"
      unitRef="usd">9600</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088097_ClassMember_AsOf_2015"
      decimals="0"
      id="ixv-258058"
      unitRef="usd">9512</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088097_ClassMember_AsOf_2016"
      decimals="0"
      id="ixv-258059"
      unitRef="usd">10346</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088097_ClassMember_AsOf_2017"
      decimals="0"
      id="ixv-258060"
      unitRef="usd">10597</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088097_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-258061"
      unitRef="usd">10494</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088097_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-258062"
      unitRef="usd">11830</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088097_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-258063"
      unitRef="usd">12750</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088097_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-258064"
      unitRef="usd">13036</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088097_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-258065"
      unitRef="usd">10975</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088097_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-258066"
      unitRef="usd">11051</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088097_ClassMember_AsOf_2024"
      decimals="0"
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      unitRef="usd">12106</oef:AcctVal>
    <oef:LineGraphAndTableMeasureName
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      id="ixv-4144">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Credit Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AcctVal
      contextRef="C000088097_1_AdditionalIndexMember_AsOf_2014"
      decimals="0"
      id="ixv-258068"
      unitRef="usd">10000</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088097_1_AdditionalIndexMember_AsOf_2015"
      decimals="0"
      id="ixv-258069"
      unitRef="usd">9957</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088097_1_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-258070"
      unitRef="usd">10868</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088097_1_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-258071"
      unitRef="usd">11074</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088097_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-258072"
      unitRef="usd">10965</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088097_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-258073"
      unitRef="usd">12389</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088097_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-258074"
      unitRef="usd">13269</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088097_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-258075"
      unitRef="usd">13569</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088097_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-258076"
      unitRef="usd">11611</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088097_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-258077"
      unitRef="usd">11709</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088097_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-258078"
      unitRef="usd">12761</oef:AcctVal>
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      id="ixv-4204">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AcctVal
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      decimals="0"
      id="ixv-258079"
      unitRef="usd">10000</oef:AcctVal>
    <oef:AcctVal
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      id="ixv-258080"
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    <oef:AcctVal
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      id="ixv-258081"
      unitRef="usd">10761</oef:AcctVal>
    <oef:AcctVal
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      decimals="0"
      id="ixv-258082"
      unitRef="usd">10814</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088097_2_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-258083"
      unitRef="usd">10701</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088097_2_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-258084"
      unitRef="usd">11789</oef:AcctVal>
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      decimals="0"
      id="ixv-258085"
      unitRef="usd">12553</oef:AcctVal>
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      contextRef="C000088097_2_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-258086"
      unitRef="usd">12542</oef:AcctVal>
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      contextRef="C000088097_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-258087"
      unitRef="usd">11098</oef:AcctVal>
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      contextRef="C000088097_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-258088"
      unitRef="usd">10965</oef:AcctVal>
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      unitRef="usd">11765</oef:AcctVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000088097_ClassMember" id="ixv-4313">AVERAGE ANNUAL TOTAL RETURNS:
&#160;
&#160;

1 Year

5 Year

10 Year


Class A (incl. 4.00% sales charge) &#160;

5.16%

-0.35%

1.93%


Class A (without 4.00% sales charge)

9.54%

0.46%

2.35%


Bloomberg U.S. Credit Bond Index

8.98%

0.59%

2.47%


Bloomberg U.S. Aggregate Bond Index

7.30%

-0.04%

1.64%




&#160;
Visit institutional.fidelity.com for more recent performance information.
&#160;


The Fund's past performance is not a good predictor of the Fund's future performance. &#160;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
&#160;



</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
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      id="ixv-258092"
      unitRef="pure">0.0193</oef:AvgAnnlRtrPct>
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      id="ixv-258093"
      unitRef="pure">0.0954</oef:AvgAnnlRtrPct>
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      id="ixv-258094"
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      id="ixv-258095"
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      id="ixv-258096"
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      id="ixv-258097"
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      id="ixv-258098"
      unitRef="pure">0.0247</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
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      id="ixv-258099"
      unitRef="pure">0.0730</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
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      decimals="INF"
      id="ixv-258100"
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    <oef:AvgAnnlRtrPct
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      decimals="INF"
      id="ixv-258101"
      unitRef="pure">0.0164</oef:AvgAnnlRtrPct>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000088097_ClassMember" id="ixv-4402">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span&gt;</oef:PerformancePastDoesNotIndicateFuture>
    <oef:NoDeductionOfTaxesTextBlock contextRef="C000088097_ClassMember" id="ixv-4406">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.&lt;/span&gt;</oef:NoDeductionOfTaxesTextBlock>
    <oef:AddlFundStatisticsTextBlock contextRef="C000088097_ClassMember" id="ixv-4413">&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 August 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;/div&gt;
&lt;span style="line-height:11px;"&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:bold;"&gt; &lt;span&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/div&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;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;$&lt;/span&gt;2,001,136,363&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;621&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;6,038,514&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="middle"&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>
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      contextRef="C000088097_InstantMember"
      decimals="0"
      id="ixv-258102"
      unitRef="usd">2001136363</us-gaap:AssetsNet>
    <oef:HoldingsCount
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      decimals="INF"
      id="ixv-258103"
      unitRef="holding">621</oef:HoldingsCount>
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      decimals="0"
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      unitRef="usd">6038514</oef:AdvisoryFeesPaidAmt>
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      id="ixv-258105"
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    <oef:HoldingsTableTextBlock contextRef="C000088097_ClassMember" id="ixv-4494">
&#160;

U.S. Government and U.S. Government Agency Obligations

9.8


AAA

0.1


AA

0.0


A

17.0


BBB

60.7


BB

6.5


B

0.7


Not Rated

0.2


Short-Term Investments and Net Other Assets (Liabilities)

5.0




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;
&#160;

Corporate Bonds

84.4


U.S. Treasury Obligations

9.8


Asset-Backed Securities

0.3


Preferred Securities

0.3


Foreign Government and Government Agency Obligations

0.1


Other Investments

0.1


Municipal Securities

0.0


Short-Term Investments and Net Other Assets (Liabilities)

5.0




ASSET ALLOCATION (% of Fund's net assets)


&#160;








United States

79.9


United Kingdom

4.0


Canada

3.3


Ireland

2.6


France

2.1


Germany

1.9


Switzerland

1.4


Netherlands

1.1


Spain

0.9


Others

2.8




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;


&#160;







</oef:HoldingsTableTextBlock>
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      id="ixv-258121"
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      contextRef="C000088097_GD_CA_Member"
      decimals="INF"
      id="ixv-258125"
      unitRef="pure">0.033</oef:PctOfNav>
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      contextRef="C000088097_GD_IE_Member"
      decimals="INF"
      id="ixv-258126"
      unitRef="pure">0.026</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088097_GD_FR_Member"
      decimals="INF"
      id="ixv-258127"
      unitRef="pure">0.021</oef:PctOfNav>
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      contextRef="C000088097_GD_DE_Member"
      decimals="INF"
      id="ixv-258128"
      unitRef="pure">0.019</oef:PctOfNav>
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      contextRef="C000088097_GD_CH_Member"
      decimals="INF"
      id="ixv-258129"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088097_GD_NL_Member"
      decimals="INF"
      id="ixv-258130"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088097_GD_ES_Member"
      decimals="INF"
      id="ixv-258131"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088097_GD_Other_Member"
      decimals="INF"
      id="ixv-258132"
      unitRef="pure">0.028</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000088097_ClassMember" id="ixv-4734">
TOP HOLDINGS
(% of Fund's net assets)

&#160;

&#160;


US Treasury Bonds

9.5
&#160;

&#160;


Bank of America Corp

2.1
&#160;

&#160;


JPMorgan Chase &amp; Co

1.9
&#160;

&#160;


Boeing Co

1.5
&#160;

&#160;


UBS Group AG

1.4
&#160;

&#160;


AerCap Ireland Capital DAC / AerCap Global Aviation Trust

1.1
&#160;

&#160;


Wells Fargo &amp; Co

1.1
&#160;

&#160;


Duke Energy Corp

1.1
&#160;

&#160;


HSBC Holdings PLC

1.1
&#160;

&#160;


CVS Health Corp

1.1
&#160;

&#160;


&#160;

21.9

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000088097_TH_0_Member"
      decimals="INF"
      id="ixv-258133"
      unitRef="pure">0.095</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088097_TH_1_Member"
      decimals="INF"
      id="ixv-258134"
      unitRef="pure">0.021</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088097_TH_2_Member"
      decimals="INF"
      id="ixv-258135"
      unitRef="pure">0.019</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088097_TH_3_Member"
      decimals="INF"
      id="ixv-258136"
      unitRef="pure">0.015</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088097_TH_4_Member"
      decimals="INF"
      id="ixv-258137"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088097_TH_5_Member"
      decimals="INF"
      id="ixv-258138"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088097_TH_6_Member"
      decimals="INF"
      id="ixv-258139"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088097_TH_7_Member"
      decimals="INF"
      id="ixv-258140"
      unitRef="pure">0.011</oef:PctOfNav>
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      contextRef="C000088097_TH_8_Member"
      decimals="INF"
      id="ixv-258141"
      unitRef="pure">0.011</oef:PctOfNav>
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      decimals="INF"
      id="ixv-258142"
      unitRef="pure">0.011</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-4916">2024-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000088099_ClassMember" id="ixv-4928">Fidelity&#xae; Corporate Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000088099_ClassMember" id="ixv-4931">Fidelity Advisor&#xae; Corporate Bond Fund Class C</oef:ClassName>
    <dei:TradingSymbol contextRef="C000088099_ClassMember" id="ixv-4935">FCCCX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000088099_ClassMember" id="ixv-4955">This annual shareholder report contains information about Fidelity&#xae; Corporate Bond Fund for the period September 1, 2023 to August 31, 2024.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000088099_ClassMember" id="ixv-4957">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000088099_ClassMember" id="ixv-4962">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="C000088099_ClassMember" id="ixv-4964">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000088099_ClassMember" id="ixv-4967">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000088099_ClassMember" id="ixv-4970">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000088099_ClassMember" id="ixv-4977">&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 year?&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&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;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;FUND COST (PREVIOUS YEAR)&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:45%; 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:24%; 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:30%; 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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:45%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class C&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:24%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;160&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:30%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;1.54&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="C000088099_ClassMember"
      decimals="0"
      id="ixv-258143"
      unitRef="usd">160</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000088099_ClassMember"
      decimals="INF"
      id="ixv-258144"
      unitRef="pure">0.0154</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000088099_ClassMember" id="ixv-5021">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&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:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds posted a strong advance for the 12 months ending August 31, 2024, helped by a late-period gain, as the bond market reflected anticipated interest-rate reductions by the U.S. Federal Reserve, which are expected to start in September. The full 12-month period was marked by high volatility.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, security selection contributed to the fund's performance versus the benchmark for the fiscal year, while sector positioning had a roughly neutral impact overall.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Bond picks among issuers in the financials sector added the most value. Having greater-than-benchmark exposure to financials also helped.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Within financials, selection among banks contributed the most, followed by investment choices among insurance companies and overall positioning in real estate investment trusts.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Picks among industrial issuers also notably aided relative performance, as did a sizable underweight in the sector.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Within industrials, selection among consumer-focused companies led the way. Positioning among information technology issuers in the benchmark provided a further boost, along with picks in the energy category.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Holding of bonds issued by electric utility companies modestly contributed.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In terms of yield-curve positioning, the fund benefited from overweight exposure to the intermediate-maturity 5-10 year portion of the curve.&#160;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Outside of corporate credit, an allocation to U.S. Treasuries and cash - held for liquidity and risk-management purposes - meaningfully detracted. This negative was somewhat offset by underweighting other government-related categories, as these bonds lagged credit in an improving market environment.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000088099_ClassMember" id="ixv-5054">How did the Fund perform over the past 10 years?
&#160;
 &#160;&#160;
CUMULATIVE PERFORMANCE
August 31, 2014 through August 31, 2024.
Initial investment of $10,000.

Class C
&#160;

$10,000

$9,833
&#160;

$10,606
&#160;

$10,792
&#160;

$10,607
&#160;

$11,856
&#160;

$12,690
&#160;

$12,876
&#160;

$10,756
&#160;

$10,832
&#160;

$11,865
&#160;


Bloomberg U.S. Credit Bond Index
&#160;

$10,000

$9,957
&#160;

$10,868
&#160;

$11,074
&#160;

$10,965
&#160;

$12,389
&#160;

$13,269
&#160;

$13,569
&#160;

$11,611
&#160;

$11,709
&#160;

$12,761
&#160;


Bloomberg U.S. Aggregate Bond Index
&#160;

$10,000

$10,156
&#160;

$10,761
&#160;

$10,814
&#160;

$10,701
&#160;

$11,789
&#160;

$12,553
&#160;

$12,542
&#160;

$11,098
&#160;

$10,965
&#160;

$11,765
&#160;


&#160;

2014

2015

2016

2017

2018

2019

2020

2021

2022

2023

2024









</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000088099_LG_ClassMember_11YR" id="ixv-5073">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class C&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AcctVal
      contextRef="C000088099_ClassMember_AsOf_2014"
      decimals="0"
      id="ixv-258145"
      unitRef="usd">10000</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088099_ClassMember_AsOf_2015"
      decimals="0"
      id="ixv-258146"
      unitRef="usd">9833</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088099_ClassMember_AsOf_2016"
      decimals="0"
      id="ixv-258147"
      unitRef="usd">10606</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088099_ClassMember_AsOf_2017"
      decimals="0"
      id="ixv-258148"
      unitRef="usd">10792</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088099_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-258149"
      unitRef="usd">10607</oef:AcctVal>
    <oef:AcctVal
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      decimals="0"
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      unitRef="usd">11856</oef:AcctVal>
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      decimals="0"
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      unitRef="usd">12690</oef:AcctVal>
    <oef:AcctVal
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    <oef:AcctVal
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      unitRef="usd">10832</oef:AcctVal>
    <oef:AcctVal
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      decimals="0"
      id="ixv-258155"
      unitRef="usd">11865</oef:AcctVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000088099_LG_1_AdditionalIndexMember_11YR"
      id="ixv-5133">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Credit Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AcctVal
      contextRef="C000088099_1_AdditionalIndexMember_AsOf_2014"
      decimals="0"
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    <oef:AcctVal
      contextRef="C000088099_1_AdditionalIndexMember_AsOf_2015"
      decimals="0"
      id="ixv-258157"
      unitRef="usd">9957</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088099_1_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-258158"
      unitRef="usd">10868</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088099_1_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-258159"
      unitRef="usd">11074</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088099_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-258160"
      unitRef="usd">10965</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088099_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
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      unitRef="usd">12389</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088099_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
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      unitRef="usd">13269</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088099_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-258163"
      unitRef="usd">13569</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088099_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-258164"
      unitRef="usd">11611</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088099_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-258165"
      unitRef="usd">11709</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088099_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-258166"
      unitRef="usd">12761</oef:AcctVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000088099_LG_2_AdditionalIndexMember_11YR"
      id="ixv-5193">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AcctVal
      contextRef="C000088099_2_AdditionalIndexMember_AsOf_2014"
      decimals="0"
      id="ixv-258167"
      unitRef="usd">10000</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088099_2_AdditionalIndexMember_AsOf_2015"
      decimals="0"
      id="ixv-258168"
      unitRef="usd">10156</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088099_2_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-258169"
      unitRef="usd">10761</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088099_2_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-258170"
      unitRef="usd">10814</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088099_2_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-258171"
      unitRef="usd">10701</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088099_2_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-258172"
      unitRef="usd">11789</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088099_2_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-258173"
      unitRef="usd">12553</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088099_2_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-258174"
      unitRef="usd">12542</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088099_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-258175"
      unitRef="usd">11098</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088099_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-258176"
      unitRef="usd">10965</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088099_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-258177"
      unitRef="usd">11765</oef:AcctVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000088099_ClassMember" id="ixv-5302">AVERAGE ANNUAL TOTAL RETURNS:
&#160;
&#160;

1 Year

5 Year

10 Year


Class C &#160;(incl. contingent deferred sales charge)

7.71%

-0.29%

1.72%


Class C

8.71%

-0.29%

1.72%


Bloomberg U.S. Credit Bond Index

8.98%

0.59%

2.47%


Bloomberg U.S. Aggregate Bond Index

7.30%

-0.04%

1.64%




&#160;
Visit institutional.fidelity.com for more recent performance information.
&#160;


The Fund's past performance is not a good predictor of the Fund's future performance. &#160;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
&#160;



</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
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      unitRef="pure">0.0771</oef:AvgAnnlRtrPct>
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      id="ixv-258179"
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    <oef:AvgAnnlRtrPct
      contextRef="C000088099_ClassMember_10YR"
      decimals="INF"
      id="ixv-258180"
      unitRef="pure">0.0172</oef:AvgAnnlRtrPct>
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      decimals="INF"
      id="ixv-258181"
      unitRef="pure">0.0871</oef:AvgAnnlRtrPct>
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      decimals="INF"
      id="ixv-258182"
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      id="ixv-258183"
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    <oef:AvgAnnlRtrPct
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      id="ixv-258184"
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      id="ixv-258185"
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      id="ixv-258186"
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      contextRef="C000088099_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-258187"
      unitRef="pure">0.0730</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
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      id="ixv-258188"
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      decimals="INF"
      id="ixv-258189"
      unitRef="pure">0.0164</oef:AvgAnnlRtrPct>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000088099_ClassMember" id="ixv-5393">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span&gt;</oef:PerformancePastDoesNotIndicateFuture>
    <oef:NoDeductionOfTaxesTextBlock contextRef="C000088099_ClassMember" id="ixv-5397">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.&lt;/span&gt;</oef:NoDeductionOfTaxesTextBlock>
    <oef:AddlFundStatisticsTextBlock contextRef="C000088099_ClassMember" id="ixv-5404">&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 August 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;/div&gt;
&lt;span style="line-height:11px;"&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:bold;"&gt; &lt;span&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/div&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;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;$&lt;/span&gt;2,001,136,363&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;621&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;6,038,514&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="middle"&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>
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      contextRef="C000088099_InstantMember"
      decimals="0"
      id="ixv-258190"
      unitRef="usd">2001136363</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000088099_InstantMember"
      decimals="INF"
      id="ixv-258191"
      unitRef="holding">621</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
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      decimals="0"
      id="ixv-258192"
      unitRef="usd">6038514</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000088099_ClassMember"
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      id="ixv-258193"
      unitRef="pure">0.30</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000088099_ClassMember" id="ixv-5485">
&#160;

U.S. Government and U.S. Government Agency Obligations

9.8


AAA

0.1


AA

0.0


A

17.0


BBB

60.7


BB

6.5


B

0.7


Not Rated

0.2


Short-Term Investments and Net Other Assets (Liabilities)

5.0




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;
&#160;

Corporate Bonds

84.4


U.S. Treasury Obligations

9.8


Asset-Backed Securities

0.3


Preferred Securities

0.3


Foreign Government and Government Agency Obligations

0.1


Other Investments

0.1


Municipal Securities

0.0


Short-Term Investments and Net Other Assets (Liabilities)

5.0




ASSET ALLOCATION (% of Fund's net assets)


&#160;








United States

79.9


United Kingdom

4.0


Canada

3.3


Ireland

2.6


France

2.1


Germany

1.9


Switzerland

1.4


Netherlands

1.1


Spain

0.9


Others

2.8




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;


&#160;







</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-258194"
      unitRef="pure">0.098</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
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    <oef:PctOfNav
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      id="ixv-258207"
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    <oef:PctOfNav
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      id="ixv-258208"
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    <oef:PctOfNav
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      id="ixv-258209"
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    <oef:PctOfNav
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      id="ixv-258211"
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    <oef:PctOfNav
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    <oef:PctOfNav
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    <oef:PctOfNav
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      id="ixv-258217"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
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      id="ixv-258218"
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    <oef:PctOfNav
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      id="ixv-258219"
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    <oef:LargestHoldingsTableTextBlock contextRef="C000088099_ClassMember" id="ixv-5725">
TOP HOLDINGS
(% of Fund's net assets)

&#160;

&#160;


US Treasury Bonds

9.5
&#160;

&#160;


Bank of America Corp

2.1
&#160;

&#160;


JPMorgan Chase &amp; Co

1.9
&#160;

&#160;


Boeing Co

1.5
&#160;

&#160;


UBS Group AG

1.4
&#160;

&#160;


AerCap Ireland Capital DAC / AerCap Global Aviation Trust

1.1
&#160;

&#160;


Wells Fargo &amp; Co

1.1
&#160;

&#160;


Duke Energy Corp

1.1
&#160;

&#160;


HSBC Holdings PLC

1.1
&#160;

&#160;


CVS Health Corp

1.1
&#160;

&#160;


&#160;

21.9

&#160;



</oef:LargestHoldingsTableTextBlock>
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      id="ixv-258221"
      unitRef="pure">0.095</oef:PctOfNav>
    <oef:PctOfNav
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    <oef:PctOfNav
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      id="ixv-258223"
      unitRef="pure">0.019</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-258224"
      unitRef="pure">0.015</oef:PctOfNav>
    <oef:PctOfNav
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      id="ixv-258225"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
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      id="ixv-258226"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
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      id="ixv-258227"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
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      id="ixv-258228"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
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      id="ixv-258229"
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      id="ixv-258230"
      unitRef="pure">0.011</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-5907">2024-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000100043_ClassMember" id="ixv-5919">Fidelity&#xae; U.S. Bond Index Fund</oef:FundName>
    <oef:ClassName contextRef="C000100043_ClassMember" id="ixv-5922">Fidelity&#xae; U.S. Bond Index Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000100043_ClassMember" id="ixv-5926">FXNAX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000100043_ClassMember" id="ixv-5946">This annual shareholder report contains information about Fidelity&#xae; U.S. Bond Index Fund for the period September 1, 2023 to August 31, 2024.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000100043_ClassMember" id="ixv-5948">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000100043_ClassMember" id="ixv-5953">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="C000100043_ClassMember" id="ixv-5955">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000100043_ClassMember" id="ixv-5958">1-800-544-8544</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000100043_ClassMember" id="ixv-5961">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000100043_ClassMember" id="ixv-5968">&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 year?&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&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;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;FUND COST (PREVIOUS YEAR)&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:45%; 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:24%; 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:30%; 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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:45%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; U.S. Bond Index Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:24%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;3&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:30%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;0.02&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="C000100043_ClassMember"
      decimals="0"
      id="ixv-258231"
      unitRef="usd">3</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000100043_ClassMember"
      decimals="INF"
      id="ixv-258232"
      unitRef="pure">0.0002</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000100043_ClassMember" id="ixv-6012">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&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:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds posted a strong advance for the 12 months ending August 31, 2024, helped by late-period gains as the bond market priced in anticipated interest-rate reductions by the U.S. Federal Reserve, which are expected to start in September. The full 12-month period was marked by high levels of volatility.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Given the large number of securities in the index (roughly 13,600) and the significant costs associated with full replication of the index, we construct the portfolio using optimization. This approach minimizes the differences between risk exposures of the fund relative to the index.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Exposures include duration, key rate durations, credit quality, sector and issuer allocation, and other factors.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000100043_ClassMember" id="ixv-6027">How did the Fund perform over the past 10 years?
&#160;
 &#160;&#160;
CUMULATIVE PERFORMANCE
August 31, 2014 through August 31, 2024.
Initial investment of $10,000.

Fidelity&#xae; U.S. Bond Index Fund
&#160;

$10,000

$10,157
&#160;

$10,764
&#160;

$10,806
&#160;

$10,674
&#160;

$11,776
&#160;

$12,539
&#160;

$12,517
&#160;

$11,075
&#160;

$10,946
&#160;

$11,736
&#160;


Bloomberg U.S. Aggregate Bond Index
&#160;

$10,000

$10,156
&#160;

$10,761
&#160;

$10,814
&#160;

$10,701
&#160;

$11,789
&#160;

$12,553
&#160;

$12,542
&#160;

$11,098
&#160;

$10,965
&#160;

$11,765
&#160;


&#160;

2014

2015

2016

2017

2018

2019

2020

2021

2022

2023

2024









</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000100043_LG_ClassMember_11YR" id="ixv-6046">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; U.S. Bond Index Fund&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AcctVal
      contextRef="C000100043_ClassMember_AsOf_2014"
      decimals="0"
      id="ixv-258233"
      unitRef="usd">10000</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000100043_ClassMember_AsOf_2015"
      decimals="0"
      id="ixv-258234"
      unitRef="usd">10157</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000100043_ClassMember_AsOf_2016"
      decimals="0"
      id="ixv-258235"
      unitRef="usd">10764</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000100043_ClassMember_AsOf_2017"
      decimals="0"
      id="ixv-258236"
      unitRef="usd">10806</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000100043_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-258237"
      unitRef="usd">10674</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000100043_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-258238"
      unitRef="usd">11776</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000100043_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-258239"
      unitRef="usd">12539</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000100043_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-258240"
      unitRef="usd">12517</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000100043_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-258241"
      unitRef="usd">11075</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000100043_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-258242"
      unitRef="usd">10946</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000100043_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-258243"
      unitRef="usd">11736</oef:AcctVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000100043_LG_1_AdditionalIndexMember_11YR"
      id="ixv-6106">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AcctVal
      contextRef="C000100043_1_AdditionalIndexMember_AsOf_2014"
      decimals="0"
      id="ixv-258244"
      unitRef="usd">10000</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000100043_1_AdditionalIndexMember_AsOf_2015"
      decimals="0"
      id="ixv-258245"
      unitRef="usd">10156</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000100043_1_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-258246"
      unitRef="usd">10761</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000100043_1_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-258247"
      unitRef="usd">10814</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000100043_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-258248"
      unitRef="usd">10701</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000100043_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-258249"
      unitRef="usd">11789</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000100043_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-258250"
      unitRef="usd">12553</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000100043_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-258251"
      unitRef="usd">12542</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000100043_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-258252"
      unitRef="usd">11098</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000100043_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-258253"
      unitRef="usd">10965</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000100043_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-258254"
      unitRef="usd">11765</oef:AcctVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000100043_ClassMember" id="ixv-6215">AVERAGE ANNUAL TOTAL RETURNS:
&#160;
&#160;

1 Year

5 Year

10 Year


Fidelity&#xae; U.S. Bond Index Fund

7.21%

-0.07%

1.61%


Bloomberg U.S. Aggregate Bond Index

7.30%

-0.04%

1.64%




&#160;
Visit www.fidelity.com for more recent performance information.
&#160;


The Fund's past performance is not a good predictor of the Fund's future performance. &#160;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
&#160;



</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
      contextRef="C000100043_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-258255"
      unitRef="pure">0.0721</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000100043_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-258256"
      unitRef="pure">-0.0007</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000100043_NoLoadClassMember_10YR"
      decimals="INF"
      id="ixv-258257"
      unitRef="pure">0.0161</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000100043_0_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-258258"
      unitRef="pure">0.0730</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000100043_0_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-258259"
      unitRef="pure">-0.0004</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000100043_0_BBIndexMember_10YR"
      decimals="INF"
      id="ixv-258260"
      unitRef="pure">0.0164</oef:AvgAnnlRtrPct>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000100043_ClassMember" id="ixv-6277">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span&gt;</oef:PerformancePastDoesNotIndicateFuture>
    <oef:NoDeductionOfTaxesTextBlock contextRef="C000100043_ClassMember" id="ixv-6281">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.&lt;/span&gt;</oef:NoDeductionOfTaxesTextBlock>
    <oef:AddlFundStatisticsTextBlock contextRef="C000100043_ClassMember" id="ixv-6288">&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 August 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;/div&gt;
&lt;span style="line-height:11px;"&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:bold;"&gt; &lt;span&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/div&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;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;$&lt;/span&gt;59,137,195,352&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;9,428&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;14,113,948&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="middle"&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;43&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="C000100043_InstantMember"
      decimals="0"
      id="ixv-258261"
      unitRef="usd">59137195352</us-gaap:AssetsNet>
    <oef:HoldingsCount
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      decimals="INF"
      id="ixv-258262"
      unitRef="holding">9428</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000100043_ClassMember"
      decimals="0"
      id="ixv-258263"
      unitRef="usd">14113948</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000100043_ClassMember"
      decimals="INF"
      id="ixv-258264"
      unitRef="pure">0.43</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000100043_ClassMember" id="ixv-6369">
&#160;

U.S. Government and U.S. Government Agency Obligations

69.5


AAA

2.8


AA

2.6


A

13.2


BBB

11.2


BB

0.4


Not Rated

0.8




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;


Short-Term Investments and Net Other Assets (Liabilities) - (0.5)%


&#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;
&#160;

U.S. Treasury Obligations

42.8


Corporate Bonds

26.4


U.S. Government Agency - Mortgage Securities

26.0


CMOs and Other Mortgage Related Securities

1.6


Foreign Government and Government Agency Obligations

1.4


Supranational Obligations

0.8


U.S. Government Agency Obligations

0.7


Municipal Securities

0.5


Asset-Backed Securities

0.3


Other Investments

0.0




ASSET ALLOCATION (% of Fund's net assets)


&#160;


Short-Term Investments and Net Other Assets (Liabilities) - (0.5)%








United States

93.9


United Kingdom

1.1


Canada

1.1


Multi-national

0.8


Japan

0.6


Mexico

0.2


Germany

0.2


Belgium

0.2


Australia

0.2


Others

1.7




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;


&#160;







</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000100043_QD_USGovernmentandUSGovernmentAgencyObligations_Member"
      decimals="INF"
      id="ixv-258265"
      unitRef="pure">0.695</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_QD_AAA_Member"
      decimals="INF"
      id="ixv-258266"
      unitRef="pure">0.028</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_QD_AA_Member"
      decimals="INF"
      id="ixv-258267"
      unitRef="pure">0.026</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_QD_A_Member"
      decimals="INF"
      id="ixv-258268"
      unitRef="pure">0.132</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_QD_BBB_Member"
      decimals="INF"
      id="ixv-258269"
      unitRef="pure">0.112</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_QD_BB_Member"
      decimals="INF"
      id="ixv-258270"
      unitRef="pure">0.004</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_QD_NotRated_Member"
      decimals="INF"
      id="ixv-258271"
      unitRef="pure">0.008</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_AA_USTreasuryObligations_Member"
      decimals="INF"
      id="ixv-258272"
      unitRef="pure">0.428</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_AA_CorporateBonds_Member"
      decimals="INF"
      id="ixv-258273"
      unitRef="pure">0.264</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_AA_USGovernmentAgencyMortgageSecurities_Member"
      decimals="INF"
      id="ixv-258274"
      unitRef="pure">0.260</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_AA_CMOsandOtherMortgageRelatedSecurities_Member"
      decimals="INF"
      id="ixv-258275"
      unitRef="pure">0.016</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_AA_ForeignGovernmentandGovernmentAgencyObligations_Member"
      decimals="INF"
      id="ixv-258276"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_AA_SupranationalObligations_Member"
      decimals="INF"
      id="ixv-258277"
      unitRef="pure">0.008</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_AA_USGovernmentAgencyObligations_Member"
      decimals="INF"
      id="ixv-258278"
      unitRef="pure">0.007</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_AA_MunicipalSecurities_Member"
      decimals="INF"
      id="ixv-258279"
      unitRef="pure">0.005</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_AA_AssetBackedSecurities_Member"
      decimals="INF"
      id="ixv-258280"
      unitRef="pure">0.003</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_AA_OtherInvestments_Member"
      decimals="INF"
      id="ixv-258281"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_GD_US_Member"
      decimals="INF"
      id="ixv-258282"
      unitRef="pure">0.939</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_GD_GB_Member"
      decimals="INF"
      id="ixv-258283"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_GD_CA_Member"
      decimals="INF"
      id="ixv-258284"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_GD_Multinational_Member"
      decimals="INF"
      id="ixv-258285"
      unitRef="pure">0.008</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_GD_JP_Member"
      decimals="INF"
      id="ixv-258286"
      unitRef="pure">0.006</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_GD_MX_Member"
      decimals="INF"
      id="ixv-258287"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_GD_DE_Member"
      decimals="INF"
      id="ixv-258288"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_GD_BE_Member"
      decimals="INF"
      id="ixv-258289"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_GD_AU_Member"
      decimals="INF"
      id="ixv-258290"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_GD_Other_Member"
      decimals="INF"
      id="ixv-258291"
      unitRef="pure">0.017</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000100043_ClassMember" id="ixv-6617">
TOP HOLDINGS
(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

34.2
&#160;

&#160;


Fannie Mae Mortgage pass-thru certificates

10.8
&#160;

&#160;


Freddie Mac Gold Pool

8.6
&#160;

&#160;


US Treasury Bonds

8.6
&#160;

&#160;


Ginnie Mae II Pool

4.9
&#160;

&#160;


Ginnie Mae I Pool

1.1
&#160;

&#160;


Freddie Mac Multiclass Mortgage participation certificates

0.9
&#160;

&#160;


Bank of America Corp

0.9
&#160;

&#160;


JPMorgan Chase &amp; Co

0.7
&#160;

&#160;


Uniform Mortgage Backed Securities

0.6
&#160;

&#160;


&#160;

71.3

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000100043_TH_0_Member"
      decimals="INF"
      id="ixv-258292"
      unitRef="pure">0.342</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_TH_1_Member"
      decimals="INF"
      id="ixv-258293"
      unitRef="pure">0.108</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_TH_2_Member"
      decimals="INF"
      id="ixv-258294"
      unitRef="pure">0.086</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_TH_3_Member"
      decimals="INF"
      id="ixv-258295"
      unitRef="pure">0.086</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_TH_4_Member"
      decimals="INF"
      id="ixv-258296"
      unitRef="pure">0.049</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_TH_5_Member"
      decimals="INF"
      id="ixv-258297"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_TH_6_Member"
      decimals="INF"
      id="ixv-258298"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_TH_7_Member"
      decimals="INF"
      id="ixv-258299"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_TH_8_Member"
      decimals="INF"
      id="ixv-258300"
      unitRef="pure">0.007</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_TH_9_Member"
      decimals="INF"
      id="ixv-258301"
      unitRef="pure">0.006</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-6799">2024-08-31</dei:DocumentPeriodEndDate>
    <oef:MaterialFundChngNoticeTextBlock contextRef="C000177581_ClassMember" id="ixv-6803">This report describes changes to the Fund that occurred during the reporting period.</oef:MaterialFundChngNoticeTextBlock>
    <oef:FundName contextRef="C000177581_ClassMember" id="ixv-6814">Fidelity Flex&#xae; U.S. Bond Index Fund</oef:FundName>
    <oef:ClassName contextRef="C000177581_ClassMember" id="ixv-6817">Fidelity Flex&#xae; U.S. Bond Index Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000177581_ClassMember" id="ixv-6821">FIBUX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000177581_ClassMember" id="ixv-6841">This annual shareholder report contains information about Fidelity Flex&#xae; U.S. Bond Index Fund for the period September 1, 2023 to August 31, 2024.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000177581_ClassMember" id="ixv-6843">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000177581_ClassMember" id="ixv-6848">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="C000177581_ClassMember" id="ixv-6850">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000177581_ClassMember" id="ixv-6853">1-800-544-3455</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000177581_ClassMember" id="ixv-6856">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000177581_ClassMember" id="ixv-6863">&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 year?&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&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;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;FUND COST (PREVIOUS YEAR)&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:45%; 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:24%; 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:30%; 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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:45%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity Flex&#xae; U.S. Bond Index Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:24%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &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:30%; 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="C000177581_ClassMember"
      decimals="0"
      id="ixv-258302"
      unitRef="usd">0</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000177581_ClassMember"
      decimals="INF"
      id="ixv-258303"
      unitRef="pure">0.0000</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000177581_ClassMember" id="ixv-6916">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&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:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds posted a strong advance for the 12 months ending August 31, 2024, helped by late-period gains as the bond market priced in anticipated interest-rate reductions by the U.S. Federal Reserve, which are expected to start in September. The full 12-month period was marked by high levels of volatility.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Given the large number of securities in the index (roughly 13,600) and the significant costs associated with full replication of the index, we construct the portfolio using optimization. This approach minimizes the differences between risk exposures of the fund relative to the index.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Exposures include duration, key rate durations, credit quality, sector and issuer allocation, and other factors.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000177581_ClassMember" id="ixv-6931">How did the Fund perform over the life of Fund?
&#160;
 &#160;&#160;
CUMULATIVE PERFORMANCE
March 9, 2017 through August 31, 2024.
Initial investment of $10,000.

Fidelity Flex&#xae; U.S. Bond Index Fund
&#160;

$10,000

$10,399
&#160;

$10,283
&#160;

$11,340
&#160;

$12,077
&#160;

$12,042
&#160;

$10,659
&#160;

$10,528
&#160;


Bloomberg U.S. Aggregate Bond Index
&#160;

$10,000

$10,410
&#160;

$10,300
&#160;

$11,348
&#160;

$12,083
&#160;

$12,073
&#160;

$10,682
&#160;

$10,555
&#160;


&#160;

2017

2018

2019

2020

2021

2022

2023

2024









</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000177581_LG_ClassMember_8YR" id="ixv-6950">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity Flex&#xae; U.S. Bond Index Fund&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AcctVal
      contextRef="C000177581_ClassMember_AsOf_2017"
      decimals="0"
      id="ixv-258304"
      unitRef="usd">10000</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000177581_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-258305"
      unitRef="usd">10399</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000177581_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-258306"
      unitRef="usd">10283</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000177581_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-258307"
      unitRef="usd">11340</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000177581_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-258308"
      unitRef="usd">12077</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000177581_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-258309"
      unitRef="usd">12042</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000177581_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-258310"
      unitRef="usd">10659</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000177581_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-258311"
      unitRef="usd">10528</oef:AcctVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000177581_LG_1_AdditionalIndexMember_8YR"
      id="ixv-6995">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AcctVal
      contextRef="C000177581_1_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-258312"
      unitRef="usd">10000</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000177581_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-258313"
      unitRef="usd">10410</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000177581_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-258314"
      unitRef="usd">10300</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000177581_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-258315"
      unitRef="usd">11348</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000177581_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-258316"
      unitRef="usd">12083</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000177581_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-258317"
      unitRef="usd">12073</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000177581_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-258318"
      unitRef="usd">10682</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000177581_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-258319"
      unitRef="usd">10555</oef:AcctVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000177581_ClassMember" id="ixv-7080">AVERAGE ANNUAL TOTAL RETURNS:
&#160;
&#160;

1 Year

5 Year

Life of Fund&#160;A


Fidelity Flex&#xae; U.S. Bond Index Fund

7.21%

-0.09%

1.63%


Bloomberg U.S. Aggregate Bond Index

7.30%

-0.04%

1.68%




A&#160; &#160;From March 9, 2017
&#160;
Visit www.401k.com for more recent performance information.
&#160;


The Fund's past performance is not a good predictor of the Fund's future performance. &#160;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
&#160;



</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
      contextRef="C000177581_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-258320"
      unitRef="pure">0.0721</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000177581_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-258321"
      unitRef="pure">-0.0009</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000177581_NoLoadClassMember_2023-09-01_2024-08-31"
      decimals="INF"
      id="ixv-258322"
      unitRef="pure">0.0163</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000177581_0_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-258323"
      unitRef="pure">0.0730</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000177581_0_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-258324"
      unitRef="pure">-0.0004</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000177581_0_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-258325"
      unitRef="pure">0.0168</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate contextRef="C000177581_ClassMember" id="ixv-7135">2017-03-09</oef:PerfInceptionDate>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000177581_ClassMember" id="ixv-7152">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span&gt;</oef:PerformancePastDoesNotIndicateFuture>
    <oef:NoDeductionOfTaxesTextBlock contextRef="C000177581_ClassMember" id="ixv-7156">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.&lt;/span&gt;</oef:NoDeductionOfTaxesTextBlock>
    <oef:AddlFundStatisticsTextBlock contextRef="C000177581_ClassMember" id="ixv-7163">&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 August 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;/div&gt;
&lt;span style="line-height:11px;"&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:bold;"&gt; &lt;span&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/div&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;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;$&lt;/span&gt;2,412,947,179&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;4,419&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;0&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="middle"&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;65&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="C000177581_InstantMember"
      decimals="0"
      id="ixv-258326"
      unitRef="usd">2412947179</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000177581_InstantMember"
      decimals="INF"
      id="ixv-258327"
      unitRef="holding">4419</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000177581_ClassMember"
      decimals="0"
      id="ixv-258328"
      unitRef="usd">0</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000177581_ClassMember"
      decimals="INF"
      id="ixv-258329"
      unitRef="pure">0.65</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000177581_ClassMember" id="ixv-7244">
&#160;

U.S. Government and U.S. Government Agency Obligations

69.5


AAA

3.3


AA

2.7


A

13.1


BBB

12.1


BB

0.4


Not Rated

0.3




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;


Short-Term Investments and Net Other Assets (Liabilities) - (1.4)%


&#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;
&#160;

U.S. Treasury Obligations

43.5


Corporate Bonds

27.3


U.S. Government Agency - Mortgage Securities

25.3


Foreign Government and Government Agency Obligations

1.5


CMOs and Other Mortgage Related Securities

1.2


Supranational Obligations

1.1


U.S. Government Agency Obligations

0.7


Municipal Securities

0.4


Asset-Backed Securities

0.2


Other Investments

0.2


Preferred Securities

0.0




ASSET ALLOCATION (% of Fund's net assets)


&#160;


Short-Term Investments and Net Other Assets (Liabilities) - (1.4)%








United States

93.2


Canada

1.2


United Kingdom

1.1


Multi-national

1.1


Japan

0.6


Mexico

0.4


Germany

0.3


Australia

0.2


Spain

0.2


Others

1.7




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;


&#160;







</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000177581_QD_USGovernmentandUSGovernmentAgencyObligations_Member"
      decimals="INF"
      id="ixv-258330"
      unitRef="pure">0.695</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_QD_AAA_Member"
      decimals="INF"
      id="ixv-258331"
      unitRef="pure">0.033</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_QD_AA_Member"
      decimals="INF"
      id="ixv-258332"
      unitRef="pure">0.027</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_QD_A_Member"
      decimals="INF"
      id="ixv-258333"
      unitRef="pure">0.131</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_QD_BBB_Member"
      decimals="INF"
      id="ixv-258334"
      unitRef="pure">0.121</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_QD_BB_Member"
      decimals="INF"
      id="ixv-258335"
      unitRef="pure">0.004</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_QD_NotRated_Member"
      decimals="INF"
      id="ixv-258336"
      unitRef="pure">0.003</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_AA_USTreasuryObligations_Member"
      decimals="INF"
      id="ixv-258337"
      unitRef="pure">0.435</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_AA_CorporateBonds_Member"
      decimals="INF"
      id="ixv-258338"
      unitRef="pure">0.273</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_AA_USGovernmentAgencyMortgageSecurities_Member"
      decimals="INF"
      id="ixv-258339"
      unitRef="pure">0.253</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_AA_ForeignGovernmentandGovernmentAgencyObligations_Member"
      decimals="INF"
      id="ixv-258340"
      unitRef="pure">0.015</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_AA_CMOsandOtherMortgageRelatedSecurities_Member"
      decimals="INF"
      id="ixv-258341"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_AA_SupranationalObligations_Member"
      decimals="INF"
      id="ixv-258342"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_AA_USGovernmentAgencyObligations_Member"
      decimals="INF"
      id="ixv-258343"
      unitRef="pure">0.007</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_AA_MunicipalSecurities_Member"
      decimals="INF"
      id="ixv-258344"
      unitRef="pure">0.004</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_AA_AssetBackedSecurities_Member"
      decimals="INF"
      id="ixv-258345"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_AA_OtherInvestments_Member"
      decimals="INF"
      id="ixv-258346"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_AA_PreferredSecurities_Member"
      decimals="INF"
      id="ixv-258347"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_GD_US_Member"
      decimals="INF"
      id="ixv-258348"
      unitRef="pure">0.932</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_GD_CA_Member"
      decimals="INF"
      id="ixv-258349"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_GD_GB_Member"
      decimals="INF"
      id="ixv-258350"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_GD_Multinational_Member"
      decimals="INF"
      id="ixv-258351"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_GD_JP_Member"
      decimals="INF"
      id="ixv-258352"
      unitRef="pure">0.006</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_GD_MX_Member"
      decimals="INF"
      id="ixv-258353"
      unitRef="pure">0.004</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_GD_DE_Member"
      decimals="INF"
      id="ixv-258354"
      unitRef="pure">0.003</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_GD_AU_Member"
      decimals="INF"
      id="ixv-258355"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_GD_ES_Member"
      decimals="INF"
      id="ixv-258356"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_GD_Other_Member"
      decimals="INF"
      id="ixv-258357"
      unitRef="pure">0.017</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000177581_ClassMember" id="ixv-7498">
TOP HOLDINGS
(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

33.9
&#160;

&#160;


Fannie Mae Mortgage pass-thru certificates

10.7
&#160;

&#160;


US Treasury Bonds

9.6
&#160;

&#160;


Freddie Mac Gold Pool

7.4
&#160;

&#160;


Ginnie Mae II Pool

4.7
&#160;

&#160;


Uniform Mortgage Backed Securities

1.4
&#160;

&#160;


Ginnie Mae I Pool

1.1
&#160;

&#160;


Bank of America Corp

0.8
&#160;

&#160;


Freddie Mac Multiclass Mortgage participation certificates

0.7
&#160;

&#160;


Goldman Sachs Group Inc/The

0.6
&#160;

&#160;


&#160;

70.9

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000177581_TH_0_Member"
      decimals="INF"
      id="ixv-258358"
      unitRef="pure">0.339</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_TH_1_Member"
      decimals="INF"
      id="ixv-258359"
      unitRef="pure">0.107</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_TH_2_Member"
      decimals="INF"
      id="ixv-258360"
      unitRef="pure">0.096</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_TH_3_Member"
      decimals="INF"
      id="ixv-258361"
      unitRef="pure">0.074</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_TH_4_Member"
      decimals="INF"
      id="ixv-258362"
      unitRef="pure">0.047</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_TH_5_Member"
      decimals="INF"
      id="ixv-258363"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_TH_6_Member"
      decimals="INF"
      id="ixv-258364"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_TH_7_Member"
      decimals="INF"
      id="ixv-258365"
      unitRef="pure">0.008</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_TH_8_Member"
      decimals="INF"
      id="ixv-258366"
      unitRef="pure">0.007</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_TH_9_Member"
      decimals="INF"
      id="ixv-258367"
      unitRef="pure">0.006</oef:PctOfNav>
    <oef:MaterialFundChngTextBlock contextRef="C000177581_ClassMember" id="ixv-7634">
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;How has the Fund changed?&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;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;This is a summary of certain changes to the Fund since September 1, 2023. For more complete information, you may review the Fund's next prospectus, which we expect to be available by&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;October 30, 2024 at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;fundresearch.fidelity.com/prospectus/sec&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or upon request at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;1-800-544-3455&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:0px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or by sending an e-mail to &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;fidfunddocuments@fidelity.com&lt;/span&gt;&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:left;"&gt;&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&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:50%; background-color:#ebf3e9;border-right:2px dashed #368627;padding:19px 19px 19px 19px;" 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;The fund added a contractual proxy and shareholder meeting expense cap during the reporting period.&lt;/span&gt;
&lt;span style="line-height:11px;"&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;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:50%; background-color:#ebf3e9;padding:19px 19px 19px 19px;" valign="top"&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:MaterialFundChngTextBlock>
    <oef:SummaryOfChngLegendTextBlock contextRef="C000177581_ClassMember" id="ixv-7640">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;This is a summary of certain changes to the Fund since September 1, 2023. For more complete information, you may review the Fund's next prospectus, which we expect to be available by&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;October 30, 2024 at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;fundresearch.fidelity.com/prospectus/sec&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or upon request at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;1-800-544-3455&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:0px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or by sending an e-mail to &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;fidfunddocuments@fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;.&lt;/span&gt;</oef:SummaryOfChngLegendTextBlock>
    <oef:UpdProspectusWebAddress contextRef="C000177581_ClassMember" id="ixv-7644">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;fundresearch.fidelity.com/prospectus/sec&lt;/span&gt;</oef:UpdProspectusWebAddress>
    <oef:UpdProspectusPhoneNumber contextRef="C000177581_ClassMember" id="ixv-7647">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;1-800-544-3455&lt;/span&gt;</oef:UpdProspectusPhoneNumber>
    <oef:UpdProspectusEmailAddress contextRef="C000177581_ClassMember" id="ixv-7651">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;fidfunddocuments@fidelity.com&lt;/span&gt;</oef:UpdProspectusEmailAddress>
    <oef:MaterialFundChngExpensesTextBlock contextRef="C000177581_ClassMember" id="ixv-7662">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The fund added a contractual proxy and shareholder meeting expense cap during the reporting period.&lt;/span&gt;
&lt;span style="line-height:11px;"&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:MaterialFundChngExpensesTextBlock>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-7722">2024-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000211071_ClassMember" id="ixv-7734">Fidelity&#xae; Series Bond Index Fund</oef:FundName>
    <oef:ClassName contextRef="C000211071_ClassMember" id="ixv-7737">Fidelity&#xae; Series Bond Index Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000211071_ClassMember" id="ixv-7741">FIFZX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000211071_ClassMember" id="ixv-7761">This annual shareholder report contains information about Fidelity&#xae; Series Bond Index Fund for the period September 1, 2023 to August 31, 2024.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000211071_ClassMember" id="ixv-7763">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000211071_ClassMember" id="ixv-7768">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="C000211071_ClassMember" id="ixv-7770">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000211071_ClassMember" id="ixv-7773">1-800-544-8544</oef:AddlInfoPhoneNumber>
    <oef:ExpensesTextBlock contextRef="C000211071_ClassMember" id="ixv-7780">&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 year?&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&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;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;FUND COST (PREVIOUS YEAR)&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:45%; 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:24%; 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:30%; 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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:45%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Series Bond Index Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:24%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &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:30%; 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="C000211071_ClassMember"
      decimals="0"
      id="ixv-258368"
      unitRef="usd">0</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000211071_ClassMember"
      decimals="INF"
      id="ixv-258369"
      unitRef="pure">0.0000</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000211071_ClassMember" id="ixv-7833">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&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:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds posted a strong advance for the 12 months ending August 31, 2024, helped by late-period gains as the bond market priced in anticipated interest-rate reductions by the U.S. Federal Reserve, which are expected to start in September. The full 12-month period was marked by high levels of volatility.&#160;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Given the large number of securities in the index (roughly 13,600) and the significant costs associated with full replication of the index, we construct the portfolio using optimization. This approach minimizes the differences between risk exposures of the fund relative to the index.&#160; Exposures include duration, key rate durations, credit quality, sector and issuer allocation, and other factors.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000211071_ClassMember" id="ixv-7845">How did the Fund perform over the life of Fund?
&#160;
 &#160;&#160;
CUMULATIVE PERFORMANCE
April 26, 2019 through August 31, 2024.
Initial investment of $10,000.

Fidelity&#xae; Series Bond Index Fund
&#160;

$10,000

$10,601
&#160;

$11,282
&#160;

$11,266
&#160;

$9,962
&#160;

$9,850
&#160;


Bloomberg U.S. Aggregate Bond Index
&#160;

$10,000

$10,596
&#160;

$11,282
&#160;

$11,272
&#160;

$9,974
&#160;

$9,855
&#160;


&#160;

2019

2020

2021

2022

2023

2024









</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000211071_LG_ClassMember_6YR" id="ixv-7864">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Series Bond Index Fund&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AcctVal
      contextRef="C000211071_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-258370"
      unitRef="usd">10000</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000211071_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-258371"
      unitRef="usd">10601</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000211071_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-258372"
      unitRef="usd">11282</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000211071_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-258373"
      unitRef="usd">11266</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000211071_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-258374"
      unitRef="usd">9962</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000211071_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-258375"
      unitRef="usd">9850</oef:AcctVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000211071_LG_1_AdditionalIndexMember_6YR"
      id="ixv-7899">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AcctVal
      contextRef="C000211071_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-258376"
      unitRef="usd">10000</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000211071_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-258377"
      unitRef="usd">10596</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000211071_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-258378"
      unitRef="usd">11282</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000211071_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-258379"
      unitRef="usd">11272</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000211071_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-258380"
      unitRef="usd">9974</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000211071_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-258381"
      unitRef="usd">9855</oef:AcctVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000211071_ClassMember" id="ixv-7968">AVERAGE ANNUAL TOTAL RETURNS:
&#160;
&#160;

1 Year

5 Year

Life of Fund&#160;A


Fidelity&#xae; Series Bond Index Fund

7.24%

-0.07%

1.03%


Bloomberg U.S. Aggregate Bond Index

7.30%

-0.04%

1.05%




A&#160; &#160;From April 26, 2019
&#160;
Visit www.fidelity.com for more recent performance information.
&#160;


The Fund's past performance is not a good predictor of the Fund's future performance. &#160;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
&#160;



</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
      contextRef="C000211071_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-258382"
      unitRef="pure">0.0724</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000211071_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-258383"
      unitRef="pure">-0.0007</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000211071_NoLoadClassMember_2023-09-01_2024-08-31"
      decimals="INF"
      id="ixv-258384"
      unitRef="pure">0.0103</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000211071_0_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-258385"
      unitRef="pure">0.0730</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000211071_0_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-258386"
      unitRef="pure">-0.0004</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000211071_0_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-258387"
      unitRef="pure">0.0105</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate contextRef="C000211071_ClassMember" id="ixv-8023">2019-04-26</oef:PerfInceptionDate>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000211071_ClassMember" id="ixv-8040">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span&gt;</oef:PerformancePastDoesNotIndicateFuture>
    <oef:NoDeductionOfTaxesTextBlock contextRef="C000211071_ClassMember" id="ixv-8044">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.&lt;/span&gt;</oef:NoDeductionOfTaxesTextBlock>
    <oef:AddlFundStatisticsTextBlock contextRef="C000211071_ClassMember" id="ixv-8051">&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 August 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;/div&gt;
&lt;span style="line-height:11px;"&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:bold;"&gt; &lt;span&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/div&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;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;$&lt;/span&gt;25,937,339,168&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;8,841&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;0&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="middle"&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;50&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>
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      decimals="INF"
      id="ixv-258389"
      unitRef="holding">8841</oef:HoldingsCount>
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      contextRef="C000211071_ClassMember"
      decimals="INF"
      id="ixv-258391"
      unitRef="pure">0.50</us-gaap:InvestmentCompanyPortfolioTurnover>
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&#160;

U.S. Government and U.S. Government Agency Obligations

70.5


AAA

2.9


AA

2.5


A

13.0


BBB

10.8


BB

0.6


Not Rated

0.6




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;
&#160;

U.S. Treasury Obligations

44.3


Corporate Bonds

25.5


U.S. Government Agency - Mortgage Securities

25.6


Foreign Government and Government Agency Obligations

1.6


CMOs and Other Mortgage Related Securities

1.4


Supranational Obligations

1.1


U.S. Government Agency Obligations

0.6


Municipal Securities

0.4


Asset-Backed Securities

0.3


Other Investments

0.1




ASSET ALLOCATION (% of Fund's net assets)


&#160;


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








United States

93.5


Canada

1.2


Multi-national

1.1


United Kingdom

1.1


Japan

0.6


Mexico

0.3


Germany

0.2


Australia

0.2


Spain

0.2


Others

1.6




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;


&#160;







</oef:HoldingsTableTextBlock>
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      unitRef="pure">0.705</oef:PctOfNav>
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      id="ixv-258393"
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      id="ixv-258394"
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      id="ixv-258402"
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      id="ixv-258403"
      unitRef="pure">0.014</oef:PctOfNav>
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      id="ixv-258404"
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      id="ixv-258405"
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    <oef:PctOfNav
      contextRef="C000211071_AA_MunicipalSecurities_Member"
      decimals="INF"
      id="ixv-258406"
      unitRef="pure">0.004</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-258407"
      unitRef="pure">0.003</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000211071_AA_OtherInvestments_Member"
      decimals="INF"
      id="ixv-258408"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000211071_GD_US_Member"
      decimals="INF"
      id="ixv-258409"
      unitRef="pure">0.935</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000211071_GD_CA_Member"
      decimals="INF"
      id="ixv-258410"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000211071_GD_Multinational_Member"
      decimals="INF"
      id="ixv-258411"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000211071_GD_GB_Member"
      decimals="INF"
      id="ixv-258412"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000211071_GD_JP_Member"
      decimals="INF"
      id="ixv-258413"
      unitRef="pure">0.006</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000211071_GD_MX_Member"
      decimals="INF"
      id="ixv-258414"
      unitRef="pure">0.003</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000211071_GD_DE_Member"
      decimals="INF"
      id="ixv-258415"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000211071_GD_AU_Member"
      decimals="INF"
      id="ixv-258416"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000211071_GD_ES_Member"
      decimals="INF"
      id="ixv-258417"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000211071_GD_Other_Member"
      decimals="INF"
      id="ixv-258418"
      unitRef="pure">0.016</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000211071_ClassMember" id="ixv-8380">
TOP HOLDINGS
(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

35.1
&#160;

&#160;


Fannie Mae Mortgage pass-thru certificates

10.7
&#160;

&#160;


US Treasury Bonds

9.2
&#160;

&#160;


Freddie Mac Gold Pool

8.1
&#160;

&#160;


Ginnie Mae II Pool

4.9
&#160;

&#160;


Ginnie Mae I Pool

1.0
&#160;

&#160;


Uniform Mortgage Backed Securities

0.9
&#160;

&#160;


Bank of America Corp

0.8
&#160;

&#160;


Freddie Mac Multiclass Mortgage participation certificates

0.8
&#160;

&#160;


JPMorgan Chase &amp; Co

0.7
&#160;

&#160;


&#160;

72.2

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-258419"
      unitRef="pure">0.351</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000211071_TH_1_Member"
      decimals="INF"
      id="ixv-258420"
      unitRef="pure">0.107</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000211071_TH_2_Member"
      decimals="INF"
      id="ixv-258421"
      unitRef="pure">0.092</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000211071_TH_3_Member"
      decimals="INF"
      id="ixv-258422"
      unitRef="pure">0.081</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000211071_TH_4_Member"
      decimals="INF"
      id="ixv-258423"
      unitRef="pure">0.049</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000211071_TH_5_Member"
      decimals="INF"
      id="ixv-258424"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000211071_TH_6_Member"
      decimals="INF"
      id="ixv-258425"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000211071_TH_7_Member"
      decimals="INF"
      id="ixv-258426"
      unitRef="pure">0.008</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000211071_TH_8_Member"
      decimals="INF"
      id="ixv-258427"
      unitRef="pure">0.008</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000211071_TH_9_Member"
      decimals="INF"
      id="ixv-258428"
      unitRef="pure">0.007</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-8562">2024-08-31</dei:DocumentPeriodEndDate>
    <oef:MaterialFundChngNoticeTextBlock contextRef="C000168450_ClassMember" id="ixv-8566">This report describes changes to the Fund that occurred during the reporting period.</oef:MaterialFundChngNoticeTextBlock>
    <oef:FundName contextRef="C000168450_ClassMember" id="ixv-8577">Fidelity&#xae; Series Government Money Market Fund</oef:FundName>
    <oef:ClassName contextRef="C000168450_ClassMember" id="ixv-8580">Fidelity&#xae; Series Government Money Market Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000168450_ClassMember" id="ixv-8584">FGNXX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000168450_ClassMember" id="ixv-8604">This annual shareholder report contains information about Fidelity&#xae; Series Government Money Market Fund for the period September 1, 2023 to August 31, 2024.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000168450_ClassMember" id="ixv-8606">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000168450_ClassMember" id="ixv-8611">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="C000168450_ClassMember" id="ixv-8613">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000168450_ClassMember" id="ixv-8616">1-800-544-8544</oef:AddlInfoPhoneNumber>
    <oef:ExpensesTextBlock contextRef="C000168450_ClassMember" id="ixv-8623">&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 year?&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&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;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;FUND COST (PREVIOUS YEAR)&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:45%; 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:24%; 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:30%; 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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:45%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Series Government Money Market Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:24%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &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:30%; 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>
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      id="ixv-258429"
      unitRef="usd">0</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000168450_ClassMember"
      decimals="INF"
      id="ixv-258430"
      unitRef="pure">0.0000</oef:ExpenseRatioPct>
    <oef:AddlFundStatisticsTextBlock contextRef="C000168450_ClassMember" id="ixv-8682">&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 August 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;/div&gt;
&lt;span style="line-height:11px;"&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:bold;"&gt; &lt;span&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/div&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;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;2,367,257,097&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;415&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;Total Advisory Fee&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;0&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="middle"&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
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    <oef:HoldingsTableTextBlock contextRef="C000168450_ClassMember" id="ixv-8751">
&#160;

EFFECTIVE MATURITY DIVERSIFICATION
(% of Fund's net assets)


&#160;
Days
&#160;


1-7

62.4

&#160;


8-30

8.1

&#160;


31-60

17.0

&#160;


61-90

5.7

&#160;


91-180

7.9

&#160;


&gt;180

0.9

&#160;


&#160;
&#160;




&#160;

Repurchase Agreements

37.6


U.S. Treasury Obligations

35.8


U.S. Government Agency - Debt

28.7




ASSET ALLOCATION (% of Fund's net assets)




Net Other Assets (Liabilities) - (2.1)%







</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
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      id="ixv-258434"
      unitRef="pure">0.624</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000168450_EMD_1_Member"
      decimals="INF"
      id="ixv-258435"
      unitRef="pure">0.081</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000168450_EMD_2_Member"
      decimals="INF"
      id="ixv-258436"
      unitRef="pure">0.170</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000168450_EMD_3_Member"
      decimals="INF"
      id="ixv-258437"
      unitRef="pure">0.057</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000168450_EMD_4_Member"
      decimals="INF"
      id="ixv-258438"
      unitRef="pure">0.079</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000168450_EMD_5_Member"
      decimals="INF"
      id="ixv-258439"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000168450_AA_RepurchaseAgreements_Member"
      decimals="INF"
      id="ixv-258440"
      unitRef="pure">0.376</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000168450_AA_USTreasuryObligations_Member"
      decimals="INF"
      id="ixv-258441"
      unitRef="pure">0.358</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000168450_AA_USGovernmentAgencyDebt_Member"
      decimals="INF"
      id="ixv-258442"
      unitRef="pure">0.287</oef:PctOfNav>
    <oef:MaterialFundChngTextBlock contextRef="C000168450_ClassMember" id="ixv-8877">
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;How has the Fund changed?&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;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;This is a summary of certain changes to the Fund since September 1, 2023. For more complete information, you may review the Fund's next prospectus, which we expect to be available by&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;October 30, 2024 at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;fundresearch.fidelity.com/prospectus/sec&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or upon request at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;1-800-544-8544&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:0px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&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:left;"&gt;&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&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:50%; background-color:#ebf3e9;border-right:2px dashed #368627;padding:19px 19px 19px 19px;" 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;The fund's principal investment risks were updated in connection with the implementation of recent rule amendments related to money market funds adopted by the SEC.&lt;/span&gt;
&lt;span style="line-height:11px;"&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;The fund's principal investment risks were updated in connection with the implementation of recent rule amendments related to money market funds adopted by the SEC.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:50%; background-color:#ebf3e9;padding:19px 19px 19px 19px;" valign="top"&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:MaterialFundChngTextBlock>
    <oef:SummaryOfChngLegendTextBlock contextRef="C000168450_ClassMember" id="ixv-8883">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;This is a summary of certain changes to the Fund since September 1, 2023. For more complete information, you may review the Fund's next prospectus, which we expect to be available by&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;October 30, 2024 at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;fundresearch.fidelity.com/prospectus/sec&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; or upon request at &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;1-800-544-8544&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:0px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;.&lt;/span&gt;</oef:SummaryOfChngLegendTextBlock>
    <oef:UpdProspectusWebAddress contextRef="C000168450_ClassMember" id="ixv-8887">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;fundresearch.fidelity.com/prospectus/sec&lt;/span&gt;</oef:UpdProspectusWebAddress>
    <oef:UpdProspectusPhoneNumber contextRef="C000168450_ClassMember" id="ixv-8890">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;1-800-544-8544&lt;/span&gt;</oef:UpdProspectusPhoneNumber>
    <oef:MaterialFundChngRisksChngTextBlock contextRef="C000168450_ClassMember" id="ixv-8902">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The fund's principal investment risks were updated in connection with the implementation of recent rule amendments related to money market funds adopted by the SEC.&lt;/span&gt;
&lt;span style="line-height:11px;"&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;The fund's principal investment risks were updated in connection with the implementation of recent rule amendments related to money market funds adopted by the SEC.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:MaterialFundChngRisksChngTextBlock>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-8964">2024-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000205023_ClassMember" id="ixv-8976">Fidelity&#xae; Corporate Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000205023_ClassMember" id="ixv-8979">Fidelity Advisor&#xae; Corporate Bond Fund Class Z</oef:ClassName>
    <dei:TradingSymbol contextRef="C000205023_ClassMember" id="ixv-8983">FIKOX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000205023_ClassMember" id="ixv-9003">This annual shareholder report contains information about Fidelity&#xae; Corporate Bond Fund for the period September 1, 2023 to August 31, 2024.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000205023_ClassMember" id="ixv-9005">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000205023_ClassMember" id="ixv-9010">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="C000205023_ClassMember" id="ixv-9012">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000205023_ClassMember" id="ixv-9015">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000205023_ClassMember" id="ixv-9018">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000205023_ClassMember" id="ixv-9025">&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 year?&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&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;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;FUND COST (PREVIOUS YEAR)&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:45%; 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:24%; 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:30%; 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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:45%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class Z&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:24%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;38&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:30%; 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="C000205023_ClassMember"
      decimals="0"
      id="ixv-258443"
      unitRef="usd">38</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000205023_ClassMember"
      decimals="INF"
      id="ixv-258444"
      unitRef="pure">0.0036</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000205023_ClassMember" id="ixv-9069">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&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:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds posted a strong advance for the 12 months ending August 31, 2024, helped by a late-period gain, as the bond market reflected anticipated interest-rate reductions by the U.S. Federal Reserve, which are expected to start in September. The full 12-month period was marked by high volatility.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, security selection contributed to the fund's performance versus the benchmark for the fiscal year, while sector positioning had a roughly neutral impact overall.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Bond picks among issuers in the financials sector added the most value. Having greater-than-benchmark exposure to financials also helped.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Within financials, selection among banks contributed the most, followed by investment choices among insurance companies and overall positioning in real estate investment trusts.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Picks among industrial issuers also notably aided relative performance, as did a sizable underweight in the sector.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Within industrials, selection among consumer-focused companies led the way. Positioning among information technology issuers in the benchmark provided a further boost, along with picks in the energy category.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Holding of bonds issued by electric utility companies modestly contributed.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In terms of yield-curve positioning, the fund benefited from overweight exposure to the intermediate-maturity 5-10 year portion of the curve.&#160;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Outside of corporate credit, an allocation to U.S. Treasuries and cash - held for liquidity and risk-management purposes - meaningfully detracted. This negative was somewhat offset by underweighting other government-related categories, as these bonds lagged credit in an improving market environment.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000205023_ClassMember" id="ixv-9102">How did the Fund perform over the life of Fund?
&#160;
 &#160;&#160;
CUMULATIVE PERFORMANCE
October 2, 2018 through August 31, 2024.
Initial investment of $10,000.

Class Z
&#160;

$10,000

$11,334
&#160;

$12,275
&#160;

$12,601
&#160;

$10,652
&#160;

$10,761
&#160;

$11,848
&#160;


Bloomberg U.S. Credit Bond Index
&#160;

$10,000

$11,331
&#160;

$12,135
&#160;

$12,409
&#160;

$10,618
&#160;

$10,708
&#160;

$11,670
&#160;


Bloomberg U.S. Aggregate Bond Index
&#160;

$10,000

$11,086
&#160;

$11,804
&#160;

$11,794
&#160;

$10,436
&#160;

$10,311
&#160;

$11,064
&#160;


&#160;

2018

2019

2020

2021

2022

2023

2024









</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000205023_LG_ClassMember_7YR" id="ixv-9121">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class Z&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AcctVal
      contextRef="C000205023_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-258445"
      unitRef="usd">10000</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000205023_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-258446"
      unitRef="usd">11334</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000205023_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-258447"
      unitRef="usd">12275</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000205023_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-258448"
      unitRef="usd">12601</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000205023_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-258449"
      unitRef="usd">10652</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000205023_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-258450"
      unitRef="usd">10761</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000205023_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-258451"
      unitRef="usd">11848</oef:AcctVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000205023_LG_1_AdditionalIndexMember_7YR"
      id="ixv-9161">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Credit Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AcctVal
      contextRef="C000205023_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-258452"
      unitRef="usd">10000</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000205023_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-258453"
      unitRef="usd">11331</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000205023_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-258454"
      unitRef="usd">12135</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000205023_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-258455"
      unitRef="usd">12409</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000205023_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-258456"
      unitRef="usd">10618</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000205023_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-258457"
      unitRef="usd">10708</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000205023_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-258458"
      unitRef="usd">11670</oef:AcctVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000205023_LG_2_AdditionalIndexMember_7YR"
      id="ixv-9201">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AcctVal
      contextRef="C000205023_2_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-258459"
      unitRef="usd">10000</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000205023_2_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-258460"
      unitRef="usd">11086</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000205023_2_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-258461"
      unitRef="usd">11804</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000205023_2_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-258462"
      unitRef="usd">11794</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000205023_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-258463"
      unitRef="usd">10436</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000205023_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-258464"
      unitRef="usd">10311</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000205023_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-258465"
      unitRef="usd">11064</oef:AcctVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000205023_ClassMember" id="ixv-9278">AVERAGE ANNUAL TOTAL RETURNS:
&#160;
&#160;

1 Year

5 Year

Life of Fund&#160;A


Class Z

10.10%

0.89%

2.91%


Bloomberg U.S. Credit Bond Index

8.98%

0.59%

2.64%


Bloomberg U.S. Aggregate Bond Index

7.30%

-0.04%

1.72%




A&#160; &#160;From October 2, 2018
&#160;
Visit institutional.fidelity.com for more recent performance information.
&#160;


The Fund's past performance is not a good predictor of the Fund's future performance. &#160;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
&#160;



</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
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      id="ixv-258466"
      unitRef="pure">0.1010</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000205023_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-258467"
      unitRef="pure">0.0089</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000205023_NoLoadClassMember_2023-09-01_2024-08-31"
      decimals="INF"
      id="ixv-258468"
      unitRef="pure">0.0291</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000205023_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-258469"
      unitRef="pure">0.0898</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000205023_0_AdditionalIndexMember_5YR"
      decimals="INF"
      id="ixv-258470"
      unitRef="pure">0.0059</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000205023_0_AdditionalIndexMember_LOC"
      decimals="INF"
      id="ixv-258471"
      unitRef="pure">0.0264</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000205023_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-258472"
      unitRef="pure">0.0730</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000205023_1_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-258473"
      unitRef="pure">-0.0004</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000205023_1_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-258474"
      unitRef="pure">0.0172</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate contextRef="C000205023_ClassMember" id="ixv-9345">2018-10-02</oef:PerfInceptionDate>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000205023_ClassMember" id="ixv-9362">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span&gt;</oef:PerformancePastDoesNotIndicateFuture>
    <oef:NoDeductionOfTaxesTextBlock contextRef="C000205023_ClassMember" id="ixv-9366">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.&lt;/span&gt;</oef:NoDeductionOfTaxesTextBlock>
    <oef:AddlFundStatisticsTextBlock contextRef="C000205023_ClassMember" id="ixv-9373">&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 August 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;/div&gt;
&lt;span style="line-height:11px;"&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:bold;"&gt; &lt;span&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/div&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;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;$&lt;/span&gt;2,001,136,363&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;621&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;6,038,514&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="middle"&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="C000205023_InstantMember"
      decimals="0"
      id="ixv-258475"
      unitRef="usd">2001136363</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000205023_InstantMember"
      decimals="INF"
      id="ixv-258476"
      unitRef="holding">621</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000205023_ClassMember"
      decimals="0"
      id="ixv-258477"
      unitRef="usd">6038514</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000205023_ClassMember"
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      id="ixv-258478"
      unitRef="pure">0.30</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000205023_ClassMember" id="ixv-9454">
&#160;

U.S. Government and U.S. Government Agency Obligations

9.8


AAA

0.1


AA

0.0


A

17.0


BBB

60.7


BB

6.5


B

0.7


Not Rated

0.2


Short-Term Investments and Net Other Assets (Liabilities)

5.0




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;
&#160;

Corporate Bonds

84.4


U.S. Treasury Obligations

9.8


Asset-Backed Securities

0.3


Preferred Securities

0.3


Foreign Government and Government Agency Obligations

0.1


Other Investments

0.1


Municipal Securities

0.0


Short-Term Investments and Net Other Assets (Liabilities)

5.0




ASSET ALLOCATION (% of Fund's net assets)


&#160;








United States

79.9


United Kingdom

4.0


Canada

3.3


Ireland

2.6


France

2.1


Germany

1.9


Switzerland

1.4


Netherlands

1.1


Spain

0.9


Others

2.8




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;


&#160;







</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000205023_QD_USGovernmentandUSGovernmentAgencyObligations_Member"
      decimals="INF"
      id="ixv-258479"
      unitRef="pure">0.098</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205023_QD_AAA_Member"
      decimals="INF"
      id="ixv-258480"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
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      id="ixv-258481"
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    <oef:PctOfNav
      contextRef="C000205023_QD_A_Member"
      decimals="INF"
      id="ixv-258482"
      unitRef="pure">0.170</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205023_QD_BBB_Member"
      decimals="INF"
      id="ixv-258483"
      unitRef="pure">0.607</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205023_QD_BB_Member"
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      id="ixv-258484"
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    <oef:PctOfNav
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      id="ixv-258485"
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    <oef:PctOfNav
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      id="ixv-258486"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205023_QD_ShortTermInvestmentsandNetOtherAssetsLiabilities_Member"
      decimals="INF"
      id="ixv-258487"
      unitRef="pure">0.050</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205023_AA_CorporateBonds_Member"
      decimals="INF"
      id="ixv-258488"
      unitRef="pure">0.844</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205023_AA_USTreasuryObligations_Member"
      decimals="INF"
      id="ixv-258489"
      unitRef="pure">0.098</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-258490"
      unitRef="pure">0.003</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205023_AA_PreferredSecurities_Member"
      decimals="INF"
      id="ixv-258491"
      unitRef="pure">0.003</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205023_AA_ForeignGovernmentandGovernmentAgencyObligations_Member"
      decimals="INF"
      id="ixv-258492"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205023_AA_OtherInvestments_Member"
      decimals="INF"
      id="ixv-258493"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205023_AA_MunicipalSecurities_Member"
      decimals="INF"
      id="ixv-258494"
      unitRef="pure">0.000</oef:PctOfNav>
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      decimals="INF"
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      contextRef="C000205023_GD_ES_Member"
      decimals="INF"
      id="ixv-258504"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-258505"
      unitRef="pure">0.028</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000205023_ClassMember" id="ixv-9694">
TOP HOLDINGS
(% of Fund's net assets)

&#160;

&#160;


US Treasury Bonds

9.5
&#160;

&#160;


Bank of America Corp

2.1
&#160;

&#160;


JPMorgan Chase &amp; Co

1.9
&#160;

&#160;


Boeing Co

1.5
&#160;

&#160;


UBS Group AG

1.4
&#160;

&#160;


AerCap Ireland Capital DAC / AerCap Global Aviation Trust

1.1
&#160;

&#160;


Wells Fargo &amp; Co

1.1
&#160;

&#160;


Duke Energy Corp

1.1
&#160;

&#160;


HSBC Holdings PLC

1.1
&#160;

&#160;


CVS Health Corp

1.1
&#160;

&#160;


&#160;

21.9

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-258506"
      unitRef="pure">0.095</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-258507"
      unitRef="pure">0.021</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205023_TH_2_Member"
      decimals="INF"
      id="ixv-258508"
      unitRef="pure">0.019</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205023_TH_3_Member"
      decimals="INF"
      id="ixv-258509"
      unitRef="pure">0.015</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-258510"
      unitRef="pure">0.014</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205023_TH_5_Member"
      decimals="INF"
      id="ixv-258511"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-258512"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-258513"
      unitRef="pure">0.011</oef:PctOfNav>
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      unitRef="pure">0.011</oef:PctOfNav>
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      id="ixv-258515"
      unitRef="pure">0.011</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-9876">2024-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000088101_ClassMember" id="ixv-9888">Fidelity&#xae; Corporate Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000088101_ClassMember" id="ixv-9891">Fidelity Advisor&#xae; Corporate Bond Fund Class I</oef:ClassName>
    <dei:TradingSymbol contextRef="C000088101_ClassMember" id="ixv-9895">FCBIX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000088101_ClassMember" id="ixv-9915">This annual shareholder report contains information about Fidelity&#xae; Corporate Bond Fund for the period September 1, 2023 to August 31, 2024.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000088101_ClassMember" id="ixv-9917">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000088101_ClassMember" id="ixv-9922">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="C000088101_ClassMember" id="ixv-9924">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000088101_ClassMember" id="ixv-9927">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000088101_ClassMember" id="ixv-9930">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000088101_ClassMember" id="ixv-9937">&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 year?&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&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;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;FUND COST (PREVIOUS YEAR)&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:45%; 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:24%; 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:30%; 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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:45%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class I&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:24%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;52&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:30%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;0.50&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="C000088101_ClassMember"
      decimals="0"
      id="ixv-258516"
      unitRef="usd">52</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000088101_ClassMember"
      decimals="INF"
      id="ixv-258517"
      unitRef="pure">0.0050</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000088101_ClassMember" id="ixv-9981">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What affected the Fund's performance this period?&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:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;U.S. taxable investment-grade bonds posted a strong advance for the 12 months ending August 31, 2024, helped by a late-period gain, as the bond market reflected anticipated interest-rate reductions by the U.S. Federal Reserve, which are expected to start in September. The full 12-month period was marked by high volatility.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Against this backdrop, security selection contributed to the fund's performance versus the benchmark for the fiscal year, while sector positioning had a roughly neutral impact overall.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Bond picks among issuers in the financials sector added the most value. Having greater-than-benchmark exposure to financials also helped.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Within financials, selection among banks contributed the most, followed by investment choices among insurance companies and overall positioning in real estate investment trusts.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Picks among industrial issuers also notably aided relative performance, as did a sizable underweight in the sector.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Within industrials, selection among consumer-focused companies led the way. Positioning among information technology issuers in the benchmark provided a further boost, along with picks in the energy category.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Holding of bonds issued by electric utility companies modestly contributed.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;In terms of yield-curve positioning, the fund benefited from overweight exposure to the intermediate-maturity 5-10 year portion of the curve.&#160;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-indent:-24px;margin-bottom:2px;margin-left:24px;margin-top:5px;margin-right:0px;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#x2022;&lt;span style="padding-right:10px"&gt;&lt;/span&gt;Outside of corporate credit, an allocation to U.S. Treasuries and cash - held for liquidity and risk-management purposes - meaningfully detracted. This negative was somewhat offset by underweighting other government-related categories, as these bonds lagged credit in an improving market environment.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000088101_ClassMember" id="ixv-10014">How did the Fund perform over the past 10 years?
&#160;
 &#160;&#160;
CUMULATIVE PERFORMANCE
August 31, 2014 through August 31, 2024.
Initial investment of $10,000.

Class I
&#160;

$10,000

$9,937
&#160;

$10,839
&#160;

$11,134
&#160;

$11,058
&#160;

$12,502
&#160;

$13,510
&#160;

$13,850
&#160;

$11,692
&#160;

$11,807
&#160;

$12,969
&#160;


Bloomberg U.S. Credit Bond Index
&#160;

$10,000

$9,957
&#160;

$10,868
&#160;

$11,074
&#160;

$10,965
&#160;

$12,389
&#160;

$13,269
&#160;

$13,569
&#160;

$11,611
&#160;

$11,709
&#160;

$12,761
&#160;


Bloomberg U.S. Aggregate Bond Index
&#160;

$10,000

$10,156
&#160;

$10,761
&#160;

$10,814
&#160;

$10,701
&#160;

$11,789
&#160;

$12,553
&#160;

$12,542
&#160;

$11,098
&#160;

$10,965
&#160;

$11,765
&#160;


&#160;

2014

2015

2016

2017

2018

2019

2020

2021

2022

2023

2024









</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000088101_LG_ClassMember_11YR" id="ixv-10033">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class I&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AcctVal
      contextRef="C000088101_ClassMember_AsOf_2014"
      decimals="0"
      id="ixv-258518"
      unitRef="usd">10000</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088101_ClassMember_AsOf_2015"
      decimals="0"
      id="ixv-258519"
      unitRef="usd">9937</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088101_ClassMember_AsOf_2016"
      decimals="0"
      id="ixv-258520"
      unitRef="usd">10839</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088101_ClassMember_AsOf_2017"
      decimals="0"
      id="ixv-258521"
      unitRef="usd">11134</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088101_ClassMember_AsOf_2018"
      decimals="0"
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      unitRef="usd">11058</oef:AcctVal>
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      decimals="0"
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      contextRef="C000088101_ClassMember_AsOf_2024"
      decimals="0"
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      unitRef="usd">12969</oef:AcctVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000088101_LG_1_AdditionalIndexMember_11YR"
      id="ixv-10093">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Credit Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AcctVal
      contextRef="C000088101_1_AdditionalIndexMember_AsOf_2014"
      decimals="0"
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    <oef:AcctVal
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      decimals="0"
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      unitRef="usd">9957</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088101_1_AdditionalIndexMember_AsOf_2016"
      decimals="0"
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      unitRef="usd">10868</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088101_1_AdditionalIndexMember_AsOf_2017"
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      unitRef="usd">11074</oef:AcctVal>
    <oef:AcctVal
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      decimals="0"
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      unitRef="usd">10965</oef:AcctVal>
    <oef:AcctVal
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      unitRef="usd">12389</oef:AcctVal>
    <oef:AcctVal
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      decimals="0"
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      unitRef="usd">13269</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088101_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-258536"
      unitRef="usd">13569</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088101_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-258537"
      unitRef="usd">11611</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088101_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-258538"
      unitRef="usd">11709</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088101_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
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      unitRef="usd">12761</oef:AcctVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000088101_LG_2_AdditionalIndexMember_11YR"
      id="ixv-10153">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;"&gt;Bloomberg U.S. Aggregate Bond Index&lt;/span&gt;</oef:LineGraphAndTableMeasureName>
    <oef:AcctVal
      contextRef="C000088101_2_AdditionalIndexMember_AsOf_2014"
      decimals="0"
      id="ixv-258540"
      unitRef="usd">10000</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088101_2_AdditionalIndexMember_AsOf_2015"
      decimals="0"
      id="ixv-258541"
      unitRef="usd">10156</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088101_2_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-258542"
      unitRef="usd">10761</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088101_2_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-258543"
      unitRef="usd">10814</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088101_2_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-258544"
      unitRef="usd">10701</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088101_2_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-258545"
      unitRef="usd">11789</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088101_2_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-258546"
      unitRef="usd">12553</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088101_2_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-258547"
      unitRef="usd">12542</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088101_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-258548"
      unitRef="usd">11098</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088101_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-258549"
      unitRef="usd">10965</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000088101_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-258550"
      unitRef="usd">11765</oef:AcctVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000088101_ClassMember" id="ixv-10262">AVERAGE ANNUAL TOTAL RETURNS:
&#160;
&#160;

1 Year

5 Year

10 Year


Class I

9.84%

0.74%

2.63%


Bloomberg U.S. Credit Bond Index

8.98%

0.59%

2.47%


Bloomberg U.S. Aggregate Bond Index

7.30%

-0.04%

1.64%




&#160;
Visit institutional.fidelity.com for more recent performance information.
&#160;


The Fund's past performance is not a good predictor of the Fund's future performance. &#160;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
&#160;



</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
      contextRef="C000088101_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-258551"
      unitRef="pure">0.0984</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088101_NoLoadClassMember_5YR"
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      id="ixv-258552"
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    <oef:AvgAnnlRtrPct
      contextRef="C000088101_NoLoadClassMember_10YR"
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      id="ixv-258553"
      unitRef="pure">0.0263</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
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      id="ixv-258554"
      unitRef="pure">0.0898</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
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      decimals="INF"
      id="ixv-258555"
      unitRef="pure">0.0059</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088101_0_AdditionalIndexMember_10YR"
      decimals="INF"
      id="ixv-258556"
      unitRef="pure">0.0247</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088101_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-258557"
      unitRef="pure">0.0730</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
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      id="ixv-258558"
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      id="ixv-258559"
      unitRef="pure">0.0164</oef:AvgAnnlRtrPct>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000088101_ClassMember" id="ixv-10336">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span&gt;</oef:PerformancePastDoesNotIndicateFuture>
    <oef:NoDeductionOfTaxesTextBlock contextRef="C000088101_ClassMember" id="ixv-10340">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.&lt;/span&gt;</oef:NoDeductionOfTaxesTextBlock>
    <oef:AddlFundStatisticsTextBlock contextRef="C000088101_ClassMember" id="ixv-10347">&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 August 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;/div&gt;
&lt;span style="line-height:11px;"&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:bold;"&gt; &lt;span&gt;&#160;&lt;/span&gt;&lt;/span&gt;&lt;/div&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;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;$&lt;/span&gt;2,001,136,363&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;621&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;6,038,514&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="middle"&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="C000088101_InstantMember"
      decimals="0"
      id="ixv-258560"
      unitRef="usd">2001136363</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000088101_InstantMember"
      decimals="INF"
      id="ixv-258561"
      unitRef="holding">621</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
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      decimals="0"
      id="ixv-258562"
      unitRef="usd">6038514</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000088101_ClassMember"
      decimals="INF"
      id="ixv-258563"
      unitRef="pure">0.30</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000088101_ClassMember" id="ixv-10428">
&#160;

U.S. Government and U.S. Government Agency Obligations

9.8


AAA

0.1


AA

0.0


A

17.0


BBB

60.7


BB

6.5


B

0.7


Not Rated

0.2


Short-Term Investments and Net Other Assets (Liabilities)

5.0




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;
&#160;

Corporate Bonds

84.4


U.S. Treasury Obligations

9.8


Asset-Backed Securities

0.3


Preferred Securities

0.3


Foreign Government and Government Agency Obligations

0.1


Other Investments

0.1


Municipal Securities

0.0


Short-Term Investments and Net Other Assets (Liabilities)

5.0




ASSET ALLOCATION (% of Fund's net assets)


&#160;








United States

79.9


United Kingdom

4.0


Canada

3.3


Ireland

2.6


France

2.1


Germany

1.9


Switzerland

1.4


Netherlands

1.1


Spain

0.9


Others

2.8




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;


&#160;







</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-258564"
      unitRef="pure">0.098</oef:PctOfNav>
    <oef:PctOfNav
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      id="ixv-258576"
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    <oef:PctOfNav
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      id="ixv-258577"
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    <oef:PctOfNav
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      id="ixv-258578"
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    <oef:PctOfNav
      contextRef="C000088101_AA_MunicipalSecurities_Member"
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      id="ixv-258579"
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      id="ixv-258580"
      unitRef="pure">0.050</oef:PctOfNav>
    <oef:PctOfNav
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      id="ixv-258581"
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    <oef:PctOfNav
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      id="ixv-258582"
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    <oef:PctOfNav
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    <oef:PctOfNav
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    <oef:PctOfNav
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      id="ixv-258587"
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    <oef:PctOfNav
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    <oef:LargestHoldingsTableTextBlock contextRef="C000088101_ClassMember" id="ixv-10668">
TOP HOLDINGS
(% of Fund's net assets)

&#160;

&#160;


US Treasury Bonds

9.5
&#160;

&#160;


Bank of America Corp

2.1
&#160;

&#160;


JPMorgan Chase &amp; Co

1.9
&#160;

&#160;


Boeing Co

1.5
&#160;

&#160;


UBS Group AG

1.4
&#160;

&#160;


AerCap Ireland Capital DAC / AerCap Global Aviation Trust

1.1
&#160;

&#160;


Wells Fargo &amp; Co

1.1
&#160;

&#160;


Duke Energy Corp

1.1
&#160;

&#160;


HSBC Holdings PLC

1.1
&#160;

&#160;


CVS Health Corp

1.1
&#160;

&#160;


&#160;

21.9

&#160;



</oef:LargestHoldingsTableTextBlock>
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      unitRef="pure">0.014</oef:PctOfNav>
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      id="ixv-258596"
      unitRef="pure">0.011</oef:PctOfNav>
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      unitRef="pure">0.011</oef:PctOfNav>
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      unitRef="pure">0.011</oef:PctOfNav>
</xbrl>
