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    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000168450_ClassMember" id="ixv-147">This annual shareholder report contains information about Fidelity&#xae; Series Government Money Market Fund for the period September 1, 2024 to August 31, 2025.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000168450_ClassMember" id="ixv-149">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000168450_ClassMember" id="ixv-154">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-156">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
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    <oef:ExpensesTextBlock contextRef="C000168450_ClassMember" id="ixv-166">&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;text-align-last:auto;"&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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:45%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Series Government Money Market Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:24%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &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:4px;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;text-align-last:auto;"&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:4px;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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:6px;color:#000000;font-style:normal;vertical-align:4px;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;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:6px;color:#000000;font-style:normal;vertical-align:4px;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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
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    <oef:AddlFundStatisticsTextBlock contextRef="C000168450_ClassMember" id="ixv-224">&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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2025)&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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&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;text-align-last:auto;"&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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&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;div style="text-align:left;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;2,577,202,995&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&gt;465&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;div style="text-align:right;text-align-last:auto;"&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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
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    <oef:HoldingsTableTextBlock contextRef="C000168450_ClassMember" id="ixv-288">
&#160;
EFFECTIVE MATURITY DIVERSIFICATION
(% of Fund's net assets)


&#160;
Days
&#160;


1-7

69.4

&#160;


8-30

7.9

&#160;


31-60

6.8

&#160;


61-90

5.8

&#160;


91-180

7.0

&#160;


&gt;180

6.8

&#160;


&#160;
&#160;




&#160;
&#160;
&#160;
Repurchase Agreements

47.4


U.S. Government Agency - Debt

33.0


U.S. Treasury Obligations

23.3




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

Repurchase Agreements - 47.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Government Agency - Debt - 33.0&#160;&#160;&#160;&#160;


&#160;

U.S. Treasury Obligations - 23.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


Net Other Assets (Liabilities) - (3.7)%


&#160;






</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
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      unitRef="pure">0.694</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000168450_EMD_1_Member"
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      id="ixv-496772"
      unitRef="pure">0.079</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000168450_EMD_2_Member"
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      id="ixv-496773"
      unitRef="pure">0.068</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-496774"
      unitRef="pure">0.058</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-496775"
      unitRef="pure">0.070</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000168450_EMD_5_Member"
      decimals="INF"
      id="ixv-496776"
      unitRef="pure">0.068</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000168450_AA_RepurchaseAgreements_Member"
      decimals="INF"
      id="ixv-496777"
      unitRef="pure">0.474</oef:PctOfNav>
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      decimals="INF"
      id="ixv-496778"
      unitRef="pure">0.330</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000168450_AA_USTreasuryObligations_Member"
      decimals="INF"
      id="ixv-496779"
      unitRef="pure">0.233</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-494">2025-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000211071_ClassMember" id="ixv-506">Fidelity&#xae; Series Bond Index Fund</oef:FundName>
    <oef:ClassName contextRef="C000211071_ClassMember" id="ixv-509">Fidelity&#xae; Series Bond Index Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000211071_ClassMember" id="ixv-513">FIFZX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000211071_ClassMember" id="ixv-532">This annual shareholder report contains information about Fidelity&#xae; Series Bond Index Fund for the period September 1, 2024 to August 31, 2025.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000211071_ClassMember" id="ixv-534">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000211071_ClassMember" id="ixv-539">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-541">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000211071_ClassMember" id="ixv-544">1-800-544-8544</oef:AddlInfoPhoneNumber>
    <oef:ExpensesTextBlock contextRef="C000211071_ClassMember" id="ixv-551">&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;text-align-last:auto;"&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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:45%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Series Bond Index Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:24%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &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:4px;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;text-align-last:auto;"&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:4px;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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:6px;color:#000000;font-style:normal;vertical-align:4px;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;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:6px;color:#000000;font-style:normal;vertical-align:4px;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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
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      decimals="0"
      id="ixv-496780"
      unitRef="usd">0</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000211071_ClassMember"
      decimals="INF"
      id="ixv-496781"
      unitRef="pure">0.0000</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000211071_ClassMember" id="ixv-603">&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;text-align-last:auto;"&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-align-last:auto;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 solid advance for the 12 months ending August 31, 2025, navigating tariff-related uncertainty since late 2024 but buoyed by relatively stable consumer inflation, a resilient economy and the expectation of policy interest-rate cuts by the U.S. Federal Reserve in the second half of 2025.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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 that backdrop, we constructed the portfolio using optimization. This approach minimizes the differences between risk exposures of the fund relative to the index. We attempt to hold all positions held by the index in the same relative proportions.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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 and other factors,&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000211071_ClassMember" id="ixv-618">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
April 26, 2019 through August 31, 2025.
Initial investment of $10,000.
Fidelity&#xae; Series Bond Index Fund


$10,000

$10,601


$11,282


$11,266


$9,962


$9,850


$10,563



Bloomberg U.S. Aggregate Bond Index


$10,000

$10,596


$11,282


$11,272


$9,974


$9,855


$10,574



&#160;

2019

2020

2021

2022

2023

2024

2025









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000211071_LG_ClassMember_7YR" id="ixv-637">&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:AccmVal
      contextRef="C000211071_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-496782"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
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      decimals="0"
      id="ixv-496783"
      unitRef="usd">10601</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000211071_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-496784"
      unitRef="usd">11282</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000211071_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-496785"
      unitRef="usd">11266</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000211071_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-496786"
      unitRef="usd">9962</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000211071_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-496787"
      unitRef="usd">9850</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000211071_ClassMember_AsOf_2025"
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      id="ixv-496788"
      unitRef="usd">10563</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000211071_LG_1_AdditionalIndexMember_7YR"
      id="ixv-670">&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:AccmVal
      contextRef="C000211071_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-496789"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000211071_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-496790"
      unitRef="usd">10596</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000211071_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-496791"
      unitRef="usd">11282</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000211071_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-496792"
      unitRef="usd">11272</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000211071_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-496793"
      unitRef="usd">9974</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000211071_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-496794"
      unitRef="usd">9855</oef:AccmVal>
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      decimals="0"
      id="ixv-496795"
      unitRef="usd">10574</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000211071_ClassMember" id="ixv-743">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

Life of Fund&#160;A


Fidelity&#xae; Series Bond Index Fund

3.08%

-0.71%

1.35%


Bloomberg U.S. Aggregate Bond Index

3.14%


-0.68%


1.37%




A&#160; &#160;From April 26, 2019

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

&#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.





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
      contextRef="C000211071_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-496796"
      unitRef="pure">0.0308</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000211071_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-496797"
      unitRef="pure">-0.0071</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000211071_NoLoadClassMember_2024-09-01_2025-08-31"
      decimals="INF"
      id="ixv-496798"
      unitRef="pure">0.0135</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000211071_0_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-496799"
      unitRef="pure">0.0314</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
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      decimals="INF"
      id="ixv-496800"
      unitRef="pure">-0.0068</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000211071_0_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-496801"
      unitRef="pure">0.0137</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000211071_Perf_2019-04-26_ClassMember"
      id="ixv-799">2019-04-26</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000211071_ClassMember" id="ixv-809">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Visit &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;www.fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; for more recent performance information.&lt;/span&gt;</oef:UpdPerfInfoLocationTextBlock>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000211071_ClassMember" id="ixv-821">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:italic;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-825">&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-831">&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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2025)&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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&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;text-align-last:auto;"&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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&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;div style="text-align:left;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;30,493,563,287&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;9,480&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;0&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&gt;55&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;div style="text-align:right;text-align-last:auto;"&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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
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    <oef:HoldingsCount
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      id="ixv-496803"
      unitRef="holding">9480</oef:HoldingsCount>
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      unitRef="pure">0.55</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000211071_ClassMember" id="ixv-906">
&#160;
U.S. Government and U.S. Government Agency Obligations

71.1


AAA

2.2


AA

2.9


A

12.7


BBB

10.4


BB

0.5


Not Rated

0.5




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 71.1


&#160;

AAA - 2.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

AA - 2.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 12.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 10.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BB - 0.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Not Rated - 0.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


Short-Term Investments and Net Other Assets (Liabilities) - (0.3)%


&#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;
&#160;
&#160;
U.S. Treasury Obligations

46.5


Corporate Bonds

26.1


U.S. Government Agency - Mortgage Securities

24.3


Foreign Government and Government Agency Obligations

1.2


CMOs and Other Mortgage Related Securities

1.2


Municipal Securities

0.3


U.S. Government Agency Obligations

0.3


Asset-Backed Securities

0.3


Other Investments

0.1




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

U.S. Treasury Obligations - 46.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Corporate Bonds - 26.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Government Agency - Mortgage Securities - 24.3


&#160;

Foreign Government and Government Agency Obligations - 1.2


&#160;

CMOs and Other Mortgage Related Securities - 1.2


&#160;

Municipal Securities - 0.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Government Agency Obligations - 0.3


&#160;

Asset-Backed Securities - 0.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Other Investments - 0.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


Short-Term Investments and Net Other Assets (Liabilities) - (0.3)%


&#160;






United States

94.3


Canada

1.2


United Kingdom

1.1


Japan

0.6


Multi-national

0.6


Mexico

0.2


Germany

0.2


Australia

0.2


Spain

0.2


Others

1.4




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 94.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 1.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 1.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Japan - 0.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Multi-national - 0.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Mexico - 0.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 0.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Australia - 0.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Spain - 0.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 1.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
</oef:HoldingsTableTextBlock>
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    <oef:LargestHoldingsTableTextBlock contextRef="C000211071_ClassMember" id="ixv-1349">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

36.9


&#160;


US Treasury Bonds

9.6


&#160;


Fannie Mae Mortgage pass-thru certificates

9.4


&#160;


Freddie Mac Gold Pool

7.9


&#160;


Ginnie Mae II Pool

4.8


&#160;


Uniform Mortgage Backed Securities

1.2


&#160;


JPMorgan Chase &amp; Co

0.8


&#160;


Ginnie Mae I Pool

0.7


&#160;


Bank of America Corp

0.7


&#160;


Freddie Mac Multifamily Structured pass-thru certificates

0.7


&#160;


&#160;

72.7

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000211071_TH_0_Member"
      decimals="INF"
      id="ixv-496832"
      unitRef="pure">0.369</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000211071_TH_1_Member"
      decimals="INF"
      id="ixv-496833"
      unitRef="pure">0.096</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000211071_TH_2_Member"
      decimals="INF"
      id="ixv-496834"
      unitRef="pure">0.094</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000211071_TH_3_Member"
      decimals="INF"
      id="ixv-496835"
      unitRef="pure">0.079</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000211071_TH_4_Member"
      decimals="INF"
      id="ixv-496836"
      unitRef="pure">0.048</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000211071_TH_5_Member"
      decimals="INF"
      id="ixv-496837"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000211071_TH_6_Member"
      decimals="INF"
      id="ixv-496838"
      unitRef="pure">0.008</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000211071_TH_7_Member"
      decimals="INF"
      id="ixv-496839"
      unitRef="pure">0.007</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000211071_TH_8_Member"
      decimals="INF"
      id="ixv-496840"
      unitRef="pure">0.007</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000211071_TH_9_Member"
      decimals="INF"
      id="ixv-496841"
      unitRef="pure">0.007</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-1520">2025-08-31</dei:DocumentPeriodEndDate>
    <oef:MaterialFundChngNoticeTextBlock contextRef="C000177581_ClassMember" id="ixv-1524">This report describes changes to the Fund that occurred during the reporting period.</oef:MaterialFundChngNoticeTextBlock>
    <oef:FundName contextRef="C000177581_ClassMember" id="ixv-1535">Fidelity Flex&#xae; U.S. Bond Index Fund</oef:FundName>
    <oef:ClassName contextRef="C000177581_ClassMember" id="ixv-1538">Fidelity Flex&#xae; U.S. Bond Index Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000177581_ClassMember" id="ixv-1542">FIBUX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000177581_ClassMember" id="ixv-1561">This annual shareholder report contains information about Fidelity Flex&#xae; U.S. Bond Index Fund for the period September 1, 2024 to August 31, 2025.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000177581_ClassMember" id="ixv-1563">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000177581_ClassMember" id="ixv-1568">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-1570">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000177581_ClassMember" id="ixv-1573">1-800-544-3455</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000177581_ClassMember" id="ixv-1576">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000177581_ClassMember" id="ixv-1583">&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;text-align-last:auto;"&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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:45%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity Flex&#xae; U.S. Bond Index Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:24%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &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:4px;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;text-align-last:auto;"&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:4px;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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:6px;color:#000000;font-style:normal;vertical-align:4px;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;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:6px;color:#000000;font-style:normal;vertical-align:4px;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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000177581_ClassMember"
      decimals="0"
      id="ixv-496842"
      unitRef="usd">0</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000177581_ClassMember"
      decimals="INF"
      id="ixv-496843"
      unitRef="pure">0.0000</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000177581_ClassMember" id="ixv-1635">&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;text-align-last:auto;"&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-align-last:auto;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 solid advance for the 12 months ending August 31, 2025, navigating tariff-related uncertainty since late 2024 but buoyed by relatively stable consumer inflation, a resilient economy and the expectation of policy interest-rate cuts by the U.S. Federal Reserve in the second half of 2025.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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 that backdrop, we constructed the portfolio using optimization. This approach minimizes the differences between risk exposures of the fund relative to the index. We attempt to hold all positions held by the index in the same relative proportions.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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 and other factors.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000177581_ClassMember" id="ixv-1650">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
March 9, 2017 through August 31, 2025.
Initial investment of $10,000.
Fidelity Flex&#xae; U.S. Bond Index Fund


$10,000

$10,399


$10,283


$11,340


$12,077


$12,042


$10,659


$10,528


$11,287



Bloomberg U.S. Aggregate Bond Index


$10,000

$10,410


$10,300


$11,348


$12,083


$12,073


$10,682


$10,555


$11,325



&#160;

2017

2018

2019

2020

2021

2022

2023

2024

2025









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000177581_LG_ClassMember_9YR" id="ixv-1669">&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:AccmVal
      contextRef="C000177581_ClassMember_AsOf_2017"
      decimals="0"
      id="ixv-496844"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000177581_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-496845"
      unitRef="usd">10399</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000177581_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-496846"
      unitRef="usd">10283</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000177581_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-496847"
      unitRef="usd">11340</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000177581_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-496848"
      unitRef="usd">12077</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000177581_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-496849"
      unitRef="usd">12042</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000177581_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-496850"
      unitRef="usd">10659</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000177581_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-496851"
      unitRef="usd">10528</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000177581_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-496852"
      unitRef="usd">11287</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000177581_LG_1_AdditionalIndexMember_9YR"
      id="ixv-1710">&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:AccmVal
      contextRef="C000177581_1_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-496853"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000177581_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-496854"
      unitRef="usd">10410</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000177581_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-496855"
      unitRef="usd">10300</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000177581_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-496856"
      unitRef="usd">11348</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000177581_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-496857"
      unitRef="usd">12083</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000177581_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-496858"
      unitRef="usd">12073</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000177581_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-496859"
      unitRef="usd">10682</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000177581_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-496860"
      unitRef="usd">10555</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000177581_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-496861"
      unitRef="usd">11325</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000177581_ClassMember" id="ixv-1797">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

Life of Fund&#160;A


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

3.13%

-0.73%

1.81%


Bloomberg U.S. Aggregate Bond Index

3.14%


-0.68%


1.85%




A&#160; &#160;From March 9, 2017

&#160;
Visit www.401k.com for more recent performance information.&#160;

&#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.





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
      contextRef="C000177581_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-496862"
      unitRef="pure">0.0313</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000177581_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-496863"
      unitRef="pure">-0.0073</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000177581_NoLoadClassMember_2024-09-01_2025-08-31"
      decimals="INF"
      id="ixv-496864"
      unitRef="pure">0.0181</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000177581_0_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-496865"
      unitRef="pure">0.0314</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000177581_0_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-496866"
      unitRef="pure">-0.0068</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000177581_0_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-496867"
      unitRef="pure">0.0185</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000177581_Perf_2017-03-09_ClassMember"
      id="ixv-1853">2017-03-09</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000177581_ClassMember" id="ixv-1863">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Visit &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;www.401k.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; for more recent performance information.&lt;/span&gt;</oef:UpdPerfInfoLocationTextBlock>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000177581_ClassMember" id="ixv-1875">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:italic;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-1879">&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-1885">&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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2025)&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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&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;text-align-last:auto;"&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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&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;div style="text-align:left;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;3,169,427,780&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;5,139&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;0&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&gt;68&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
    <us-gaap:AssetsNet
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      decimals="0"
      id="ixv-496868"
      unitRef="usd">3169427780</us-gaap:AssetsNet>
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      decimals="INF"
      id="ixv-496869"
      unitRef="holding">5139</oef:HoldingsCount>
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    <us-gaap:InvestmentCompanyPortfolioTurnover
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      unitRef="pure">0.68</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000177581_ClassMember" id="ixv-1960">
&#160;
U.S. Government and U.S. Government Agency Obligations

70.9


AAA

2.5


AA

2.6


A

12.5


BBB

10.6


BB

0.6


Not Rated

0.3


Short-Term Investments and Net Other Assets (Liabilities)

0.0




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 70.9


&#160;

AAA - 2.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

AA - 2.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 12.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 10.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BB - 0.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Not Rated - 0.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 0.0


&#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;
&#160;
&#160;
U.S. Treasury Obligations

46.4


Corporate Bonds

26.2


U.S. Government Agency - Mortgage Securities

24.0


Foreign Government and Government Agency Obligations

1.2


CMOs and Other Mortgage Related Securities

1.0


U.S. Government Agency Obligations

0.5


Municipal Securities

0.3


Asset-Backed Securities

0.3


Other Investments

0.1


Preferred Securities

0.0


Short-Term Investments and Net Other Assets (Liabilities)

0.0




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

U.S. Treasury Obligations - 46.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Corporate Bonds - 26.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Government Agency - Mortgage Securities - 24.0


&#160;

Foreign Government and Government Agency Obligations - 1.2


&#160;

CMOs and Other Mortgage Related Securities - 1.0


&#160;

U.S. Government Agency Obligations - 0.5


&#160;

Municipal Securities - 0.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Asset-Backed Securities - 0.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Other Investments - 0.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Preferred Securities - 0.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 0.0


&#160;






United States

94.2


United Kingdom

1.0


Canada

1.0


Multi-national

0.7


Japan

0.6


Mexico

0.3


Germany

0.3


Spain

0.2


Australia

0.2


Others

1.5




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 94.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 1.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 1.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Multi-national - 0.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Japan - 0.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Mexico - 0.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 0.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Spain - 0.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Australia - 0.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 1.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
</oef:HoldingsTableTextBlock>
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      unitRef="pure">0.709</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
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    <oef:PctOfNav
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      decimals="INF"
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    <oef:PctOfNav
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      decimals="INF"
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    <oef:PctOfNav
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      decimals="INF"
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    <oef:PctOfNav
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    <oef:PctOfNav
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    <oef:PctOfNav
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    <oef:PctOfNav
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      id="ixv-496880"
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    <oef:PctOfNav
      contextRef="C000177581_AA_CorporateBonds_Member"
      decimals="INF"
      id="ixv-496881"
      unitRef="pure">0.262</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-496882"
      unitRef="pure">0.240</oef:PctOfNav>
    <oef:PctOfNav
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      unitRef="pure">0.012</oef:PctOfNav>
    <oef:PctOfNav
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      id="ixv-496884"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_AA_USGovernmentAgencyObligations_Member"
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      id="ixv-496885"
      unitRef="pure">0.005</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_AA_MunicipalSecurities_Member"
      decimals="INF"
      id="ixv-496886"
      unitRef="pure">0.003</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_AA_AssetBackedSecurities_Member"
      decimals="INF"
      id="ixv-496887"
      unitRef="pure">0.003</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_AA_OtherInvestments_Member"
      decimals="INF"
      id="ixv-496888"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_AA_PreferredSecurities_Member"
      decimals="INF"
      id="ixv-496889"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_AA_ShortTermInvestmentsandNetOtherAssetsLiabilities_Member"
      decimals="INF"
      id="ixv-496890"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_GD_US_Member"
      decimals="INF"
      id="ixv-496891"
      unitRef="pure">0.942</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_GD_GB_Member"
      decimals="INF"
      id="ixv-496892"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_GD_CA_Member"
      decimals="INF"
      id="ixv-496893"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_GD_Multinational_Member"
      decimals="INF"
      id="ixv-496894"
      unitRef="pure">0.007</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_GD_JP_Member"
      decimals="INF"
      id="ixv-496895"
      unitRef="pure">0.006</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_GD_MX_Member"
      decimals="INF"
      id="ixv-496896"
      unitRef="pure">0.003</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_GD_DE_Member"
      decimals="INF"
      id="ixv-496897"
      unitRef="pure">0.003</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_GD_ES_Member"
      decimals="INF"
      id="ixv-496898"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_GD_AU_Member"
      decimals="INF"
      id="ixv-496899"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_GD_Other_Member"
      decimals="INF"
      id="ixv-496900"
      unitRef="pure">0.015</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000177581_ClassMember" id="ixv-2434">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

37.0


&#160;


Fannie Mae Mortgage pass-thru certificates

9.9


&#160;


US Treasury Bonds

9.4


&#160;


Freddie Mac Gold Pool

6.7


&#160;


Ginnie Mae II Pool

4.7


&#160;


Uniform Mortgage Backed Securities

1.7


&#160;


Ginnie Mae I Pool

0.8


&#160;


Bank of America Corp

0.7


&#160;


JPMorgan Chase &amp; Co

0.7


&#160;


Freddie Mac Multifamily Structured pass-thru certificates

0.6


&#160;


&#160;

72.2

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000177581_TH_0_Member"
      decimals="INF"
      id="ixv-496901"
      unitRef="pure">0.370</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_TH_1_Member"
      decimals="INF"
      id="ixv-496902"
      unitRef="pure">0.099</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_TH_2_Member"
      decimals="INF"
      id="ixv-496903"
      unitRef="pure">0.094</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_TH_3_Member"
      decimals="INF"
      id="ixv-496904"
      unitRef="pure">0.067</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_TH_4_Member"
      decimals="INF"
      id="ixv-496905"
      unitRef="pure">0.047</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_TH_5_Member"
      decimals="INF"
      id="ixv-496906"
      unitRef="pure">0.017</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_TH_6_Member"
      decimals="INF"
      id="ixv-496907"
      unitRef="pure">0.008</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_TH_7_Member"
      decimals="INF"
      id="ixv-496908"
      unitRef="pure">0.007</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000177581_TH_8_Member"
      decimals="INF"
      id="ixv-496909"
      unitRef="pure">0.007</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-496910"
      unitRef="pure">0.006</oef:PctOfNav>
    <oef:MaterialFundChngTextBlock contextRef="C000177581_ClassMember" id="ixv-2559">
&lt;div style="text-align:left;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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, 2024. 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, 2025 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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&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;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The fund's contractural proxy and shareholder meeting expense cap expired during the reporting period.&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:MaterialFundChngTextBlock>
    <oef:SummaryOfChngLegendTextBlock contextRef="C000177581_ClassMember" id="ixv-2565">&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, 2024. 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, 2025 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-2569">&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-2572">&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-2576">&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-2587">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;The fund's contractural proxy and shareholder meeting expense cap expired during the reporting period.&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:MaterialFundChngExpensesTextBlock>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-2645">2025-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000069436_ClassMember" id="ixv-2657">Fidelity&#xae; Series Investment Grade Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000069436_ClassMember" id="ixv-2660">Fidelity&#xae; Series Investment Grade Bond Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000069436_ClassMember" id="ixv-2664">FSIGX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000069436_ClassMember" id="ixv-2683">This annual shareholder report contains information about Fidelity&#xae; Series Investment Grade Bond Fund for the period September 1, 2024 to August 31, 2025.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000069436_ClassMember" id="ixv-2685">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000069436_ClassMember" id="ixv-2690">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-2692">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000069436_ClassMember" id="ixv-2695">1-800-544-8544</oef:AddlInfoPhoneNumber>
    <oef:ExpensesTextBlock contextRef="C000069436_ClassMember" id="ixv-2702">&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;text-align-last:auto;"&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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:45%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Series Investment Grade Bond Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:24%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &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:4px;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;text-align-last:auto;"&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:4px;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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:6px;color:#000000;font-style:normal;vertical-align:4px;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;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:6px;color:#000000;font-style:normal;vertical-align:4px;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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000069436_ClassMember"
      decimals="0"
      id="ixv-496911"
      unitRef="usd">0</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000069436_ClassMember"
      decimals="INF"
      id="ixv-496912"
      unitRef="pure">0.0000</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000069436_ClassMember" id="ixv-2754">&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;text-align-last:auto;"&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-align-last:auto;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 solid advance for the 12 months ending August 31, 2025, navigating tariff-related uncertainty since late 2024 but buoyed by relatively stable consumer inflation, a resilient economy and the expectation of policy interest-rate cuts by the U.S. Federal Reserve in the second half of 2025.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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 outperformance of the Bloomberg U.S. Aggregate Bond Index for the fiscal year.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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;Specifically, fund holdings in the corporate segment made a notable contribution to relative performance, led by picks among financials, particularly REITs and banks.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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;Overweight holdings and picks among asset-backed securities, particularly collateralized loan obligations, and commercial mortgage-backed securities each helped relative performance the past 12 months.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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 underweights in mortgage-backed securities and U.S. Treasurys buoyed relative performance as well.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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 portfolio's yield-curve positioning also provided a boost to performance versus the benchmark.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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 the bonds of industrial firms within the corporate sector detracted versus the benchmark.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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 modestly longer duration relative to the benchmark also hurt.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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;Notable changes to the fund over the past 12 months included management's decision to gradually lower the fund's overall risk profile by reducing exposure to investment-grade corporate bonds and increasing the allocation to U.S. Treasurys.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000069436_ClassMember" id="ixv-2787">How did the Fund perform over the past 10 years?

 &#160;&#160;
CUMULATIVE PERFORMANCE
August 31, 2015 through August 31, 2025.
Initial investment of $10,000.
Fidelity&#xae; Series Investment Grade Bond Fund


$10,000

$10,687


$10,841


$10,793


$11,890


$12,860


$13,125


$11,667


$11,665


$12,632


$13,104



Bloomberg U.S. Aggregate Bond Index


$10,000

$10,597


$10,649


$10,537


$11,609


$12,360


$12,350


$10,928


$10,797


$11,585


$11,949



&#160;

2015

2016

2017

2018

2019

2020

2021

2022

2023

2024

2025









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000069436_LG_ClassMember_11YR" id="ixv-2806">&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:AccmVal
      contextRef="C000069436_ClassMember_AsOf_2015"
      decimals="0"
      id="ixv-496913"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000069436_ClassMember_AsOf_2016"
      decimals="0"
      id="ixv-496914"
      unitRef="usd">10687</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000069436_ClassMember_AsOf_2017"
      decimals="0"
      id="ixv-496915"
      unitRef="usd">10841</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000069436_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-496916"
      unitRef="usd">10793</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000069436_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-496917"
      unitRef="usd">11890</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000069436_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-496918"
      unitRef="usd">12860</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000069436_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-496919"
      unitRef="usd">13125</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000069436_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-496920"
      unitRef="usd">11667</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000069436_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-496921"
      unitRef="usd">11665</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000069436_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-496922"
      unitRef="usd">12632</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000069436_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-496923"
      unitRef="usd">13104</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000069436_LG_1_AdditionalIndexMember_11YR"
      id="ixv-2855">&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:AccmVal
      contextRef="C000069436_1_AdditionalIndexMember_AsOf_2015"
      decimals="0"
      id="ixv-496924"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000069436_1_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-496925"
      unitRef="usd">10597</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000069436_1_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-496926"
      unitRef="usd">10649</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000069436_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-496927"
      unitRef="usd">10537</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000069436_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-496928"
      unitRef="usd">11609</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000069436_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-496929"
      unitRef="usd">12360</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000069436_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-496930"
      unitRef="usd">12350</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000069436_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-496931"
      unitRef="usd">10928</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000069436_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-496932"
      unitRef="usd">10797</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000069436_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-496933"
      unitRef="usd">11585</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000069436_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-496934"
      unitRef="usd">11949</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000069436_ClassMember" id="ixv-2956">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

10 Year


Fidelity&#xae; Series Investment Grade Bond Fund

3.74%

0.38%

2.74%


Bloomberg U.S. Aggregate Bond Index

3.14%


-0.68%


1.80%




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

&#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.





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
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      decimals="INF"
      id="ixv-496935"
      unitRef="pure">0.0374</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000069436_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-496936"
      unitRef="pure">0.0038</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000069436_NoLoadClassMember_10YR"
      decimals="INF"
      id="ixv-496937"
      unitRef="pure">0.0274</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000069436_0_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-496938"
      unitRef="pure">0.0314</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000069436_0_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-496939"
      unitRef="pure">-0.0068</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000069436_0_BBIndexMember_10YR"
      decimals="INF"
      id="ixv-496940"
      unitRef="pure">0.0180</oef:AvgAnnlRtrPct>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000069436_ClassMember" id="ixv-3012">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Visit &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;www.fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; for more recent performance information.&lt;/span&gt;</oef:UpdPerfInfoLocationTextBlock>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000069436_ClassMember" id="ixv-3024">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:italic;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-3028">&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-3034">&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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2025)&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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&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;text-align-last:auto;"&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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&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;div style="text-align:left;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;37,233,906,749&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;4,878&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;0&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&gt;203&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;div style="text-align:right;text-align-last:auto;"&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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
    <us-gaap:AssetsNet
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      decimals="0"
      id="ixv-496941"
      unitRef="usd">37233906749</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000069436_InstantMember"
      decimals="INF"
      id="ixv-496942"
      unitRef="holding">4878</oef:HoldingsCount>
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      decimals="0"
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      unitRef="usd">0</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000069436_ClassMember"
      decimals="INF"
      id="ixv-496944"
      unitRef="pure">2.03</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000069436_ClassMember" id="ixv-3109">
&#160;
U.S. Government and U.S. Government Agency Obligations

65.5


AAA

7.7


AA

0.6


A

6.5


BBB

14.1


BB

1.8


B

1.0


CCC,CC,C

0.1


Not Rated

5.1




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 65.5


&#160;

AAA - 7.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

AA - 0.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 6.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 14.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BB - 1.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

B - 1.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CCC,CC,C - 0.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Not Rated - 5.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


Short-Term Investments and Net Other Assets (Liabilities) - (2.4)%


&#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;
&#160;
&#160;
U.S. Treasury Obligations

43.8


U.S. Government Agency - Mortgage Securities

21.7


Corporate Bonds

21.1


Asset-Backed Securities

8.7


CMOs and Other Mortgage Related Securities

6.7


Other Investments

0.2


Options

0.1


Foreign Government and Government Agency Obligations

0.1


Preferred Securities

0.0




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

U.S. Treasury Obligations - 43.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Government Agency - Mortgage Securities - 21.7


&#160;

Corporate Bonds - 21.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Asset-Backed Securities - 8.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CMOs and Other Mortgage Related Securities - 6.7


&#160;

Other Investments - 0.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Options - 0.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Foreign Government and Government Agency Obligations - 0.1


&#160;

Preferred Securities - 0.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


Short-Term Investments and Net Other Assets (Liabilities) - (2.4)%


&#160;






United States

89.6


Grand Cayman (UK Overseas Ter)

5.3


United Kingdom

1.0


Mexico

0.9


Ireland

0.7


Bailiwick Of Jersey

0.4


Switzerland

0.4


France

0.4


Germany

0.3


Others

1.0




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 89.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Grand Cayman (UK Overseas Ter) - 5.3&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 1.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Mexico - 0.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Ireland - 0.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Bailiwick Of Jersey - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Switzerland - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

France - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 0.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 1.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
</oef:HoldingsTableTextBlock>
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    <oef:PctOfNav
      contextRef="C000069436_QD_AAA_Member"
      decimals="INF"
      id="ixv-496946"
      unitRef="pure">0.077</oef:PctOfNav>
    <oef:PctOfNav
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    <oef:PctOfNav
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      decimals="INF"
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      unitRef="pure">0.065</oef:PctOfNav>
    <oef:PctOfNav
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    <oef:PctOfNav
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    <oef:PctOfNav
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    <oef:PctOfNav
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    <oef:PctOfNav
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      unitRef="pure">0.051</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000069436_AA_USTreasuryObligations_Member"
      decimals="INF"
      id="ixv-496954"
      unitRef="pure">0.438</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-496955"
      unitRef="pure">0.217</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000069436_AA_CorporateBonds_Member"
      decimals="INF"
      id="ixv-496956"
      unitRef="pure">0.211</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000069436_AA_AssetBackedSecurities_Member"
      decimals="INF"
      id="ixv-496957"
      unitRef="pure">0.087</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000069436_AA_CMOsandOtherMortgageRelatedSecurities_Member"
      decimals="INF"
      id="ixv-496958"
      unitRef="pure">0.067</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000069436_AA_OtherInvestments_Member"
      decimals="INF"
      id="ixv-496959"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000069436_AA_Options_Member"
      decimals="INF"
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      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
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    <oef:PctOfNav
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      id="ixv-496962"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000069436_GD_US_Member"
      decimals="INF"
      id="ixv-496963"
      unitRef="pure">0.896</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000069436_GD_GrandCaymanUKOverseasTer_Member"
      decimals="INF"
      id="ixv-496964"
      unitRef="pure">0.053</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000069436_GD_GB_Member"
      decimals="INF"
      id="ixv-496965"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000069436_GD_MX_Member"
      decimals="INF"
      id="ixv-496966"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000069436_GD_IE_Member"
      decimals="INF"
      id="ixv-496967"
      unitRef="pure">0.007</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000069436_GD_BailiwickOfJersey_Member"
      decimals="INF"
      id="ixv-496968"
      unitRef="pure">0.004</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000069436_GD_CH_Member"
      decimals="INF"
      id="ixv-496969"
      unitRef="pure">0.004</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000069436_GD_FR_Member"
      decimals="INF"
      id="ixv-496970"
      unitRef="pure">0.004</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000069436_GD_DE_Member"
      decimals="INF"
      id="ixv-496971"
      unitRef="pure">0.003</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000069436_GD_Other_Member"
      decimals="INF"
      id="ixv-496972"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000069436_ClassMember" id="ixv-3578">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

33.7


&#160;


US Treasury Bonds

10.1


&#160;


Fannie Mae Mortgage pass-thru certificates

7.9


&#160;


Ginnie Mae II Pool

5.3


&#160;


Freddie Mac Gold Pool

4.7


&#160;


Uniform Mortgage Backed Securities

2.6


&#160;


JPMorgan Chase &amp; Co

1.0


&#160;


Petroleos Mexicanos

0.9


&#160;


Ginnie Mae I Pool

0.8


&#160;


Wells Fargo &amp; Co

0.8


&#160;


&#160;

67.8

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000069436_TH_0_Member"
      decimals="INF"
      id="ixv-496973"
      unitRef="pure">0.337</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000069436_TH_1_Member"
      decimals="INF"
      id="ixv-496974"
      unitRef="pure">0.101</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000069436_TH_2_Member"
      decimals="INF"
      id="ixv-496975"
      unitRef="pure">0.079</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000069436_TH_3_Member"
      decimals="INF"
      id="ixv-496976"
      unitRef="pure">0.053</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000069436_TH_4_Member"
      decimals="INF"
      id="ixv-496977"
      unitRef="pure">0.047</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000069436_TH_5_Member"
      decimals="INF"
      id="ixv-496978"
      unitRef="pure">0.026</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000069436_TH_6_Member"
      decimals="INF"
      id="ixv-496979"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000069436_TH_7_Member"
      decimals="INF"
      id="ixv-496980"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000069436_TH_8_Member"
      decimals="INF"
      id="ixv-496981"
      unitRef="pure">0.008</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000069436_TH_9_Member"
      decimals="INF"
      id="ixv-496982"
      unitRef="pure">0.008</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-3749">2025-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000100043_ClassMember" id="ixv-3761">Fidelity&#xae; U.S. Bond Index Fund</oef:FundName>
    <oef:ClassName contextRef="C000100043_ClassMember" id="ixv-3764">Fidelity&#xae; U.S. Bond Index Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000100043_ClassMember" id="ixv-3768">FXNAX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000100043_ClassMember" id="ixv-3787">This annual shareholder report contains information about Fidelity&#xae; U.S. Bond Index Fund for the period September 1, 2024 to August 31, 2025.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000100043_ClassMember" id="ixv-3789">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000100043_ClassMember" id="ixv-3794">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-3796">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000100043_ClassMember" id="ixv-3799">1-800-544-8544</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000100043_ClassMember" id="ixv-3802">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000100043_ClassMember" id="ixv-3809">&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;text-align-last:auto;"&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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:45%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; U.S. Bond Index Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:24%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &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;text-align-last:auto;"&gt;0.03&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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000100043_ClassMember"
      decimals="0"
      id="ixv-496983"
      unitRef="usd">3</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000100043_ClassMember"
      decimals="INF"
      id="ixv-496984"
      unitRef="pure">0.0003</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000100043_ClassMember" id="ixv-3851">&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;text-align-last:auto;"&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-align-last:auto;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 solid advance for the 12 months ending August 31, 2025, navigating tariff-related uncertainty since late 2024 but buoyed by relatively stable consumer inflation, a resilient economy and the expectation of policy interest-rate cuts by the U.S. Federal Reserve in the second half of 2025.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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 that backdrop, we constructed the portfolio using optimization. This approach minimizes the differences between risk exposures of the fund relative to the index. We attempt to hold all positions held by the index in the same relative proportions.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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 and other factors.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000100043_ClassMember" id="ixv-3866">How did the Fund perform over the past 10 years?

 &#160;&#160;
CUMULATIVE PERFORMANCE
August 31, 2015 through August 31, 2025.
Initial investment of $10,000.
Fidelity&#xae; U.S. Bond Index Fund


$10,000

$10,598


$10,639


$10,509


$11,594


$12,346


$12,324


$10,904


$10,777


$11,554


$11,913



Bloomberg U.S. Aggregate Bond Index


$10,000

$10,597


$10,649


$10,537


$11,609


$12,360


$12,350


$10,928


$10,797


$11,585


$11,949



&#160;

2015

2016

2017

2018

2019

2020

2021

2022

2023

2024

2025









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000100043_LG_ClassMember_11YR" id="ixv-3885">&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:AccmVal
      contextRef="C000100043_ClassMember_AsOf_2015"
      decimals="0"
      id="ixv-496985"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000100043_ClassMember_AsOf_2016"
      decimals="0"
      id="ixv-496986"
      unitRef="usd">10598</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000100043_ClassMember_AsOf_2017"
      decimals="0"
      id="ixv-496987"
      unitRef="usd">10639</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000100043_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-496988"
      unitRef="usd">10509</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000100043_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-496989"
      unitRef="usd">11594</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000100043_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-496990"
      unitRef="usd">12346</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000100043_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-496991"
      unitRef="usd">12324</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000100043_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-496992"
      unitRef="usd">10904</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000100043_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-496993"
      unitRef="usd">10777</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000100043_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-496994"
      unitRef="usd">11554</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000100043_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-496995"
      unitRef="usd">11913</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000100043_LG_1_AdditionalIndexMember_11YR"
      id="ixv-3934">&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:AccmVal
      contextRef="C000100043_1_AdditionalIndexMember_AsOf_2015"
      decimals="0"
      id="ixv-496996"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000100043_1_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-496997"
      unitRef="usd">10597</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000100043_1_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-496998"
      unitRef="usd">10649</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000100043_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-496999"
      unitRef="usd">10537</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000100043_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-497000"
      unitRef="usd">11609</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000100043_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-497001"
      unitRef="usd">12360</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000100043_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-497002"
      unitRef="usd">12350</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000100043_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-497003"
      unitRef="usd">10928</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000100043_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-497004"
      unitRef="usd">10797</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000100043_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-497005"
      unitRef="usd">11585</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000100043_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-497006"
      unitRef="usd">11949</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000100043_ClassMember" id="ixv-4035">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

10 Year


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

3.11%

-0.71%

1.77%


Bloomberg U.S. Aggregate Bond Index

3.14%


-0.68%


1.80%




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

&#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.





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
      contextRef="C000100043_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-497007"
      unitRef="pure">0.0311</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000100043_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-497008"
      unitRef="pure">-0.0071</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000100043_NoLoadClassMember_10YR"
      decimals="INF"
      id="ixv-497009"
      unitRef="pure">0.0177</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000100043_0_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-497010"
      unitRef="pure">0.0314</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000100043_0_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-497011"
      unitRef="pure">-0.0068</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000100043_0_BBIndexMember_10YR"
      decimals="INF"
      id="ixv-497012"
      unitRef="pure">0.0180</oef:AvgAnnlRtrPct>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000100043_ClassMember" id="ixv-4092">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Visit &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;www.fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; for more recent performance information.&lt;/span&gt;</oef:UpdPerfInfoLocationTextBlock>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000100043_ClassMember" id="ixv-4104">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:italic;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-4108">&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-4114">&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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2025)&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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&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;text-align-last:auto;"&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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&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;div style="text-align:left;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;66,160,308,255&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;10,138&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;15,319,318&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&gt;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;div style="text-align:right;text-align-last:auto;"&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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
    <us-gaap:AssetsNet
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      decimals="0"
      id="ixv-497013"
      unitRef="usd">66160308255</us-gaap:AssetsNet>
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      decimals="INF"
      id="ixv-497014"
      unitRef="holding">10138</oef:HoldingsCount>
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      unitRef="usd">15319318</oef:AdvisoryFeesPaidAmt>
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      id="ixv-497016"
      unitRef="pure">0.45</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000100043_ClassMember" id="ixv-4189">
&#160;
U.S. Government and U.S. Government Agency Obligations

71.5


AAA

1.9


AA

2.4


A

12.6


BBB

10.6


BB

0.3


Not Rated

0.8




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 71.5


&#160;

AAA - 1.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

AA - 2.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 12.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 10.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BB - 0.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Not Rated - 0.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


Short-Term Investments and Net Other Assets (Liabilities) - (0.1)%


&#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;
&#160;
&#160;
U.S. Treasury Obligations

46.8


Corporate Bonds

25.3


U.S. Government Agency - Mortgage Securities

24.5


CMOs and Other Mortgage Related Securities

1.3


Foreign Government and Government Agency Obligations

1.2


Municipal Securities

0.4


Asset-Backed Securities

0.3


U.S. Government Agency Obligations

0.2


Other Investments

0.1




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

U.S. Treasury Obligations - 46.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Corporate Bonds - 25.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Government Agency - Mortgage Securities - 24.5


&#160;

CMOs and Other Mortgage Related Securities - 1.3


&#160;

Foreign Government and Government Agency Obligations - 1.2


&#160;

Municipal Securities - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Asset-Backed Securities - 0.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Government Agency Obligations - 0.2


&#160;

Other Investments - 0.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


Short-Term Investments and Net Other Assets (Liabilities) - (0.1)%


&#160;






United States

94.7


United Kingdom

1.0


Canada

1.0


Japan

0.6


Multi-national

0.4


Mexico

0.2


Australia

0.2


Germany

0.2


Belgium

0.2


Others

1.5




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 94.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 1.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 1.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Japan - 0.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Multi-national - 0.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Mexico - 0.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Australia - 0.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 0.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Belgium - 0.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 1.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-497017"
      unitRef="pure">0.715</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_QD_AAA_Member"
      decimals="INF"
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      unitRef="pure">0.019</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_QD_AA_Member"
      decimals="INF"
      id="ixv-497019"
      unitRef="pure">0.024</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_QD_A_Member"
      decimals="INF"
      id="ixv-497020"
      unitRef="pure">0.126</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_QD_BBB_Member"
      decimals="INF"
      id="ixv-497021"
      unitRef="pure">0.106</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_QD_BB_Member"
      decimals="INF"
      id="ixv-497022"
      unitRef="pure">0.003</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_QD_NotRated_Member"
      decimals="INF"
      id="ixv-497023"
      unitRef="pure">0.008</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_AA_USTreasuryObligations_Member"
      decimals="INF"
      id="ixv-497024"
      unitRef="pure">0.468</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_AA_CorporateBonds_Member"
      decimals="INF"
      id="ixv-497025"
      unitRef="pure">0.253</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_AA_USGovernmentAgencyMortgageSecurities_Member"
      decimals="INF"
      id="ixv-497026"
      unitRef="pure">0.245</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_AA_CMOsandOtherMortgageRelatedSecurities_Member"
      decimals="INF"
      id="ixv-497027"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_AA_ForeignGovernmentandGovernmentAgencyObligations_Member"
      decimals="INF"
      id="ixv-497028"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_AA_MunicipalSecurities_Member"
      decimals="INF"
      id="ixv-497029"
      unitRef="pure">0.004</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_AA_AssetBackedSecurities_Member"
      decimals="INF"
      id="ixv-497030"
      unitRef="pure">0.003</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_AA_USGovernmentAgencyObligations_Member"
      decimals="INF"
      id="ixv-497031"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_AA_OtherInvestments_Member"
      decimals="INF"
      id="ixv-497032"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_GD_US_Member"
      decimals="INF"
      id="ixv-497033"
      unitRef="pure">0.947</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_GD_GB_Member"
      decimals="INF"
      id="ixv-497034"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_GD_CA_Member"
      decimals="INF"
      id="ixv-497035"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_GD_JP_Member"
      decimals="INF"
      id="ixv-497036"
      unitRef="pure">0.006</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_GD_Multinational_Member"
      decimals="INF"
      id="ixv-497037"
      unitRef="pure">0.004</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_GD_MX_Member"
      decimals="INF"
      id="ixv-497038"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_GD_AU_Member"
      decimals="INF"
      id="ixv-497039"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_GD_DE_Member"
      decimals="INF"
      id="ixv-497040"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_GD_BE_Member"
      decimals="INF"
      id="ixv-497041"
      unitRef="pure">0.002</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_GD_Other_Member"
      decimals="INF"
      id="ixv-497042"
      unitRef="pure">0.015</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000100043_ClassMember" id="ixv-4632">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

38.0


&#160;


Fannie Mae Mortgage pass-thru certificates

10.0


&#160;


US Treasury Bonds

8.8


&#160;


Freddie Mac Gold Pool

8.0


&#160;


Ginnie Mae II Pool

4.7


&#160;


Ginnie Mae I Pool

0.9


&#160;


Uniform Mortgage Backed Securities

0.9


&#160;


Freddie Mac Multifamily Structured pass-thru certificates

0.8


&#160;


Bank of America Corp

0.8


&#160;


JPMorgan Chase &amp; Co

0.7


&#160;


&#160;

73.6

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000100043_TH_0_Member"
      decimals="INF"
      id="ixv-497043"
      unitRef="pure">0.380</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_TH_1_Member"
      decimals="INF"
      id="ixv-497044"
      unitRef="pure">0.100</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_TH_2_Member"
      decimals="INF"
      id="ixv-497045"
      unitRef="pure">0.088</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_TH_3_Member"
      decimals="INF"
      id="ixv-497046"
      unitRef="pure">0.080</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_TH_4_Member"
      decimals="INF"
      id="ixv-497047"
      unitRef="pure">0.047</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_TH_5_Member"
      decimals="INF"
      id="ixv-497048"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_TH_6_Member"
      decimals="INF"
      id="ixv-497049"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_TH_7_Member"
      decimals="INF"
      id="ixv-497050"
      unitRef="pure">0.008</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_TH_8_Member"
      decimals="INF"
      id="ixv-497051"
      unitRef="pure">0.008</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000100043_TH_9_Member"
      decimals="INF"
      id="ixv-497052"
      unitRef="pure">0.007</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-4803">2025-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000153158_ClassMember" id="ixv-4815">Fidelity&#xae; Series Short-Term Credit Fund</oef:FundName>
    <oef:ClassName contextRef="C000153158_ClassMember" id="ixv-4818">Fidelity&#xae; Series Short-Term Credit Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000153158_ClassMember" id="ixv-4822">FYBTX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000153158_ClassMember" id="ixv-4841">This annual shareholder report contains information about Fidelity&#xae; Series Short-Term Credit Fund for the period September 1, 2024 to August 31, 2025.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000153158_ClassMember" id="ixv-4843">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000153158_ClassMember" id="ixv-4848">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-4850">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000153158_ClassMember" id="ixv-4853">1-800-544-8544</oef:AddlInfoPhoneNumber>
    <oef:ExpensesTextBlock contextRef="C000153158_ClassMember" id="ixv-4860">&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;text-align-last:auto;"&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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:45%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Series Short-Term Credit Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:24%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &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:4px;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;text-align-last:auto;"&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:4px;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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:6px;color:#000000;font-style:normal;vertical-align:4px;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;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:6px;color:#000000;font-style:normal;vertical-align:4px;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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
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    <oef:ExpenseRatioPct
      contextRef="C000153158_ClassMember"
      decimals="INF"
      id="ixv-497054"
      unitRef="pure">0.0000</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000153158_ClassMember" id="ixv-4912">&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;text-align-last:auto;"&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-align-last:auto;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 solid advance for the 12 months ending August 31, 2025, navigating tariff-related uncertainty since late 2024 but buoyed by relatively stable consumer inflation, a resilient economy and the expectation of policy interest-rate cuts by the U.S. Federal Reserve in the second half of 2025.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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, the co-managers' security selection among corporate bonds contributed to performance versus the benchmark for the fiscal year. Within corporates, debt holdings among financial institutions, especially banks, and industrial firms, particularly in the consumer cyclical and consumer non-cyclical segments, added notable value.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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, also meaningfully contributed.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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;Non-benchmark holdings among commercial mortgage-backed securities also hurt.&#160;&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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 made up roughly 73% of fund assets, up from 71% a year ago but underweight versus the benchmark average of 84%. Exposure to ABS stood at roughly 15% as of August 31, while CMBS stood at about 4% and U.S. Treasurys approximately 6% of the portfolio at the close of the fiscal year.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000153158_ClassMember" id="ixv-4936">How did the Fund perform over the past 10 years?

 &#160;&#160;
CUMULATIVE PERFORMANCE
August 31, 2015 through August 31, 2025.
Initial investment of $10,000.
Fidelity&#xae; Series Short-Term Credit Fund


$10,000

$10,198


$10,319


$10,404


$10,926


$11,401


$11,510


$11,081


$11,417


$12,262


$12,906



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


$10,000

$10,238


$10,401


$10,463


$10,995


$11,436


$11,544


$11,098


$11,344


$12,143


$12,777



Bloomberg U.S. Aggregate Bond Index


$10,000

$10,597


$10,649


$10,537


$11,609


$12,360


$12,350


$10,928


$10,797


$11,585


$11,949



&#160;

2015

2016

2017

2018

2019

2020

2021

2022

2023

2024

2025









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000153158_LG_ClassMember_11YR" id="ixv-4955">&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:AccmVal
      contextRef="C000153158_ClassMember_AsOf_2015"
      decimals="0"
      id="ixv-497055"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000153158_ClassMember_AsOf_2016"
      decimals="0"
      id="ixv-497056"
      unitRef="usd">10198</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000153158_ClassMember_AsOf_2017"
      decimals="0"
      id="ixv-497057"
      unitRef="usd">10319</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000153158_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-497058"
      unitRef="usd">10404</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000153158_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-497059"
      unitRef="usd">10926</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000153158_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-497060"
      unitRef="usd">11401</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000153158_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-497061"
      unitRef="usd">11510</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000153158_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-497062"
      unitRef="usd">11081</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000153158_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-497063"
      unitRef="usd">11417</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000153158_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-497064"
      unitRef="usd">12262</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000153158_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-497065"
      unitRef="usd">12906</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000153158_LG_1_AdditionalIndexMember_11YR"
      id="ixv-5004">&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:AccmVal
      contextRef="C000153158_1_AdditionalIndexMember_AsOf_2015"
      decimals="0"
      id="ixv-497066"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000153158_1_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-497067"
      unitRef="usd">10238</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000153158_1_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-497068"
      unitRef="usd">10401</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000153158_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-497069"
      unitRef="usd">10463</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000153158_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-497070"
      unitRef="usd">10995</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000153158_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-497071"
      unitRef="usd">11436</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000153158_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-497072"
      unitRef="usd">11544</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000153158_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-497073"
      unitRef="usd">11098</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000153158_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-497074"
      unitRef="usd">11344</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000153158_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-497075"
      unitRef="usd">12143</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000153158_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-497076"
      unitRef="usd">12777</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000153158_LG_2_AdditionalIndexMember_11YR"
      id="ixv-5053">&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:AccmVal
      contextRef="C000153158_2_AdditionalIndexMember_AsOf_2015"
      decimals="0"
      id="ixv-497077"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000153158_2_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-497078"
      unitRef="usd">10597</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000153158_2_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-497079"
      unitRef="usd">10649</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000153158_2_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-497080"
      unitRef="usd">10537</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000153158_2_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-497081"
      unitRef="usd">11609</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000153158_2_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-497082"
      unitRef="usd">12360</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000153158_2_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-497083"
      unitRef="usd">12350</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000153158_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-497084"
      unitRef="usd">10928</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000153158_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-497085"
      unitRef="usd">10797</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000153158_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-497086"
      unitRef="usd">11585</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000153158_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-497087"
      unitRef="usd">11949</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000153158_ClassMember" id="ixv-5154">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

10 Year


Fidelity&#xae; Series Short-Term Credit Fund

5.26%

2.51%

2.58%


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

5.22%


2.24%


2.48%


Bloomberg U.S. Aggregate Bond Index

3.14%


-0.68%


1.80%




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

&#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.





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
      contextRef="C000153158_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-497088"
      unitRef="pure">0.0526</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000153158_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-497089"
      unitRef="pure">0.0251</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000153158_NoLoadClassMember_10YR"
      decimals="INF"
      id="ixv-497090"
      unitRef="pure">0.0258</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000153158_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-497091"
      unitRef="pure">0.0522</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000153158_0_AdditionalIndexMember_5YR"
      decimals="INF"
      id="ixv-497092"
      unitRef="pure">0.0224</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000153158_0_AdditionalIndexMember_10YR"
      decimals="INF"
      id="ixv-497093"
      unitRef="pure">0.0248</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000153158_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-497094"
      unitRef="pure">0.0314</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000153158_1_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-497095"
      unitRef="pure">-0.0068</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000153158_1_BBIndexMember_10YR"
      decimals="INF"
      id="ixv-497096"
      unitRef="pure">0.0180</oef:AvgAnnlRtrPct>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000153158_ClassMember" id="ixv-5225">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Visit &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;www.fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; for more recent performance information.&lt;/span&gt;</oef:UpdPerfInfoLocationTextBlock>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000153158_ClassMember" id="ixv-5237">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:italic;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-5241">&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-5247">&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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2025)&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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&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;text-align-last:auto;"&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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&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;div style="text-align:left;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;429,099,093&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;445&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;0&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&gt;67&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;div style="text-align:right;text-align-last:auto;"&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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
    <us-gaap:AssetsNet
      contextRef="C000153158_InstantMember"
      decimals="0"
      id="ixv-497097"
      unitRef="usd">429099093</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000153158_InstantMember"
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&#160;
U.S. Government and U.S. Government Agency Obligations

7.5


AAA

14.2


AA

0.8


A

28.9


BBB

41.9


BB

2.1


Not Rated

3.6


Short-Term Investments and Net Other Assets (Liabilities)

1.0




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 7.5


&#160;

AAA - 14.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

AA - 0.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 28.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 41.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BB - 2.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Not Rated - 3.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 1.0


&#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;
&#160;
&#160;
Corporate Bonds

72.1


Asset-Backed Securities

15.3


U.S. Treasury Obligations

6.7


CMOs and Other Mortgage Related Securities

3.9


U.S. Government Agency - Mortgage Securities

0.8


Other Investments

0.2


Short-Term Investments and Net Other Assets (Liabilities)

1.0




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

Corporate Bonds - 72.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Asset-Backed Securities - 15.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Treasury Obligations - 6.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CMOs and Other Mortgage Related Securities - 3.9


&#160;

U.S. Government Agency - Mortgage Securities - 0.8


&#160;

Other Investments - 0.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 1.0


&#160;






United States

74.7


United Kingdom

6.2


Germany

4.3


Grand Cayman (UK Overseas Ter)

4.2


Canada

2.0


Ireland

1.9


Japan

1.3


Netherlands

1.1


France

0.9


Others

3.4




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 74.7&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 6.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 4.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Grand Cayman (UK Overseas Ter) - 4.2&#160;&#160;&#160;&#160;


&#160;

Canada - 2.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Ireland - 1.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Japan - 1.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Netherlands - 1.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

France - 0.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 3.4&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
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      unitRef="pure">0.019</oef:PctOfNav>
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      decimals="INF"
      id="ixv-497122"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-497123"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-497124"
      unitRef="pure">0.009</oef:PctOfNav>
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      unitRef="pure">0.034</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000153158_ClassMember" id="ixv-5744">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

6.7


&#160;


Bank of America Corp

3.4


&#160;


General Motors Financial Co Inc

2.3


&#160;


JPMorgan Chase &amp; Co

2.2


&#160;


Wells Fargo &amp; Co

2.2


&#160;


Morgan Stanley

2.1


&#160;


Citigroup Inc

2.0


&#160;


Goldman Sachs Group Inc/The

1.7


&#160;


Ford Motor Credit Co LLC

1.5


&#160;


HSBC Holdings PLC

1.5


&#160;


&#160;

25.6

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-497126"
      unitRef="pure">0.067</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000153158_TH_1_Member"
      decimals="INF"
      id="ixv-497127"
      unitRef="pure">0.034</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000153158_TH_2_Member"
      decimals="INF"
      id="ixv-497128"
      unitRef="pure">0.023</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000153158_TH_3_Member"
      decimals="INF"
      id="ixv-497129"
      unitRef="pure">0.022</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000153158_TH_4_Member"
      decimals="INF"
      id="ixv-497130"
      unitRef="pure">0.022</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-497131"
      unitRef="pure">0.021</oef:PctOfNav>
    <oef:PctOfNav
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    <oef:PctOfNav
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      unitRef="pure">0.017</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-497134"
      unitRef="pure">0.015</oef:PctOfNav>
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      unitRef="pure">0.015</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-5915">2025-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000088100_ClassMember" id="ixv-5927">Fidelity&#xae; Corporate Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000088100_ClassMember" id="ixv-5930">Fidelity Advisor&#xae; Corporate Bond Fund Class M</oef:ClassName>
    <dei:TradingSymbol contextRef="C000088100_ClassMember" id="ixv-5934">FCBTX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000088100_ClassMember" id="ixv-5953">This annual shareholder report contains information about Fidelity&#xae; Corporate Bond Fund for the period September 1, 2024 to August 31, 2025.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000088100_ClassMember" id="ixv-5955">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000088100_ClassMember" id="ixv-5960">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-5962">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000088100_ClassMember" id="ixv-5965">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000088100_ClassMember" id="ixv-5968">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000088100_ClassMember" id="ixv-5975">&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;text-align-last:auto;"&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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:45%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class M&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:24%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;82&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;text-align-last:auto;"&gt;0.80&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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000088100_ClassMember"
      decimals="0"
      id="ixv-497136"
      unitRef="usd">82</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000088100_ClassMember"
      decimals="INF"
      id="ixv-497137"
      unitRef="pure">0.0080</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000088100_ClassMember" id="ixv-6017">&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;text-align-last:auto;"&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-align-last:auto;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 solid advance for the 12 months ending August 31, 2025, navigating tariff-related uncertainty since late 2024 but buoyed by relatively stable consumer inflation, a resilient economy and the expectation of policy interest-rate cuts by the U.S. Federal Reserve in the second half of 2025.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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 Bloomberg U.S. Credit Bond Index for the fiscal year, whereas sector positioning detracted.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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 companies in the industrials sector helped most, led by issuers in the communications, consumer non-cyclicals and capital goods industries.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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 communications, notable contributors included Warner Bros. Discovery and Charter Communications. In consumer non-cyclicals, pharmaceutical company Bayer was a standout, while Boeing drove the contribution in capital goods.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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 financial issuers also notably aided relative performance. Here, bonds from banks, real estate investment trusts and insurance companies helped most.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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. Treasurys and cash - held for liquidity and risk-management purposes - meaningfully detracted from the fund's relative result. This negative was somewhat offset by steering clear of 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;text-align-last:auto;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 yield curve strategy of concentrating the portfolio's holdings in the five- to seven-year portion of the curve had a neutral impact on relative performance.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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;During the period, the fund's managers continued to emphasize issuers rated BBB, as they believe there is opportunity for alpha potential over time resulting from improving credit quality. They modestly added bonds rated A, in response to tight spreads and uncertainty.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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;Noteworthy positioning changes included reducing exposure to non-bank financials (e.g., finance companies) and redeploying the capital into industrials and utilities.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000088100_ClassMember" id="ixv-6050">How did the Fund perform over the past 10 years?

 &#160;&#160;
CUMULATIVE PERFORMANCE
August 31, 2015 through August 31, 2025.
Initial investment of $10,000&#160;and the current sales charge was paid.
Class M


$9,600

$10,433


$10,678


$10,566


$11,901


$12,820


$13,104


$11,027


$11,098


$12,151


$12,590



Bloomberg U.S. Credit Bond Index


$10,000

$10,914


$11,122


$11,012


$12,443


$13,326


$13,627


$11,661


$11,759


$12,816


$13,318



Bloomberg U.S. Aggregate Bond Index


$10,000

$10,597


$10,649


$10,537


$11,609


$12,360


$12,350


$10,928


$10,797


$11,585


$11,949



&#160;

2015

2016

2017

2018

2019

2020

2021

2022

2023

2024

2025









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000088100_LG_ClassMember_11YR" id="ixv-6071">&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:AccmVal
      contextRef="C000088100_ClassMember_AsOf_2015"
      decimals="0"
      id="ixv-497138"
      unitRef="usd">9600</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088100_ClassMember_AsOf_2016"
      decimals="0"
      id="ixv-497139"
      unitRef="usd">10433</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088100_ClassMember_AsOf_2017"
      decimals="0"
      id="ixv-497140"
      unitRef="usd">10678</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088100_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-497141"
      unitRef="usd">10566</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088100_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-497142"
      unitRef="usd">11901</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088100_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-497143"
      unitRef="usd">12820</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088100_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-497144"
      unitRef="usd">13104</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088100_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-497145"
      unitRef="usd">11027</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088100_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-497146"
      unitRef="usd">11098</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088100_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-497147"
      unitRef="usd">12151</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088100_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-497148"
      unitRef="usd">12590</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000088100_LG_1_AdditionalIndexMember_11YR"
      id="ixv-6120">&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:AccmVal
      contextRef="C000088100_1_AdditionalIndexMember_AsOf_2015"
      decimals="0"
      id="ixv-497149"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088100_1_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-497150"
      unitRef="usd">10914</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088100_1_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-497151"
      unitRef="usd">11122</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088100_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-497152"
      unitRef="usd">11012</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088100_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-497153"
      unitRef="usd">12443</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088100_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-497154"
      unitRef="usd">13326</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088100_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-497155"
      unitRef="usd">13627</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088100_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-497156"
      unitRef="usd">11661</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088100_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-497157"
      unitRef="usd">11759</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088100_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-497158"
      unitRef="usd">12816</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088100_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-497159"
      unitRef="usd">13318</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000088100_LG_2_AdditionalIndexMember_11YR"
      id="ixv-6169">&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:AccmVal
      contextRef="C000088100_2_AdditionalIndexMember_AsOf_2015"
      decimals="0"
      id="ixv-497160"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088100_2_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-497161"
      unitRef="usd">10597</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088100_2_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-497162"
      unitRef="usd">10649</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088100_2_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-497163"
      unitRef="usd">10537</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088100_2_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-497164"
      unitRef="usd">11609</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088100_2_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-497165"
      unitRef="usd">12360</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088100_2_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-497166"
      unitRef="usd">12350</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088100_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-497167"
      unitRef="usd">10928</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088100_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-497168"
      unitRef="usd">10797</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088100_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-497169"
      unitRef="usd">11585</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088100_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-497170"
      unitRef="usd">11949</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000088100_ClassMember" id="ixv-6270">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

10 Year


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

-0.53%

-1.17%


2.33%


Class M (without 4.00% sales charge)

3.61%

-0.36%

2.75%


Bloomberg U.S. Credit Bond Index

3.92%


-0.01%


2.91%


Bloomberg U.S. Aggregate Bond Index

3.14%


-0.68%


1.80%




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

&#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.





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
      contextRef="C000088100_ClassMember_1YR"
      decimals="INF"
      id="ixv-497171"
      unitRef="pure">-0.0053</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088100_ClassMember_5YR"
      decimals="INF"
      id="ixv-497172"
      unitRef="pure">-0.0117</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088100_ClassMember_10YR"
      decimals="INF"
      id="ixv-497173"
      unitRef="pure">0.0233</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088100_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-497174"
      unitRef="pure">0.0361</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088100_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-497175"
      unitRef="pure">-0.0036</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088100_NoLoadClassMember_10YR"
      decimals="INF"
      id="ixv-497176"
      unitRef="pure">0.0275</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088100_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-497177"
      unitRef="pure">0.0392</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088100_0_AdditionalIndexMember_5YR"
      decimals="INF"
      id="ixv-497178"
      unitRef="pure">-0.0001</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088100_0_AdditionalIndexMember_10YR"
      decimals="INF"
      id="ixv-497179"
      unitRef="pure">0.0291</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088100_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-497180"
      unitRef="pure">0.0314</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088100_1_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-497181"
      unitRef="pure">-0.0068</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088100_1_BBIndexMember_10YR"
      decimals="INF"
      id="ixv-497182"
      unitRef="pure">0.0180</oef:AvgAnnlRtrPct>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000088100_ClassMember" id="ixv-6360">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Visit &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;institutional.fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; for more recent performance information.&lt;/span&gt;</oef:UpdPerfInfoLocationTextBlock>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000088100_ClassMember" id="ixv-6372">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:italic;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-6376">&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-6382">&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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2025)&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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&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;text-align-last:auto;"&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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&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;div style="text-align:left;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;2,081,012,659&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;600&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;7,046,841&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;div style="text-align:right;text-align-last:auto;"&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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
    <us-gaap:AssetsNet
      contextRef="C000088100_InstantMember"
      decimals="0"
      id="ixv-497183"
      unitRef="usd">2081012659</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000088100_InstantMember"
      decimals="INF"
      id="ixv-497184"
      unitRef="holding">600</oef:HoldingsCount>
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    <oef:HoldingsTableTextBlock contextRef="C000088100_ClassMember" id="ixv-6457">
&#160;
U.S. Government and U.S. Government Agency Obligations

9.2


AAA

0.1


AA

0.0


A

23.1


BBB

57.0


BB

4.9


B

1.3


Not Rated

0.1


Short-Term Investments and Net Other Assets (Liabilities)

4.3




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 9.2


&#160;

AAA - 0.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

AA - 0.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 23.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 57.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BB - 4.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

B - 1.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Not Rated - 0.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 4.3


&#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;
&#160;
&#160;
Corporate Bonds

85.3


U.S. Treasury Obligations

9.2


Asset-Backed Securities

0.6


Preferred Securities

0.3


Foreign Government and Government Agency Obligations

0.1


CMOs and Other Mortgage Related Securities

0.1


Other Investments

0.1


Municipal Securities

0.0


Short-Term Investments and Net Other Assets (Liabilities)

4.3




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

Corporate Bonds - 85.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Treasury Obligations - 9.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Asset-Backed Securities - 0.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Preferred Securities - 0.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Foreign Government and Government Agency Obligations - 0.1


&#160;

CMOs and Other Mortgage Related Securities - 0.1


&#160;

Other Investments - 0.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Municipal Securities - 0.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 4.3


&#160;






United States

80.5


Canada

3.5


United Kingdom

3.3


Ireland

2.6


Germany

2.0


Japan

1.3


Switzerland

1.1


Netherlands

1.0


France

0.9


Others

3.8




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 80.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 3.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 3.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Ireland - 2.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 2.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Japan - 1.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Switzerland - 1.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Netherlands - 1.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

France - 0.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 3.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
</oef:HoldingsTableTextBlock>
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    <oef:PctOfNav
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      decimals="INF"
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      id="ixv-497195"
      unitRef="pure">0.043</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088100_AA_CorporateBonds_Member"
      decimals="INF"
      id="ixv-497196"
      unitRef="pure">0.853</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-497197"
      unitRef="pure">0.092</oef:PctOfNav>
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      contextRef="C000088100_AA_AssetBackedSecurities_Member"
      decimals="INF"
      id="ixv-497198"
      unitRef="pure">0.006</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088100_AA_PreferredSecurities_Member"
      decimals="INF"
      id="ixv-497199"
      unitRef="pure">0.003</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-497200"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088100_AA_CMOsandOtherMortgageRelatedSecurities_Member"
      decimals="INF"
      id="ixv-497201"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-497202"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-497203"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-497204"
      unitRef="pure">0.043</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088100_GD_US_Member"
      decimals="INF"
      id="ixv-497205"
      unitRef="pure">0.805</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088100_GD_CA_Member"
      decimals="INF"
      id="ixv-497206"
      unitRef="pure">0.035</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088100_GD_GB_Member"
      decimals="INF"
      id="ixv-497207"
      unitRef="pure">0.033</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088100_GD_IE_Member"
      decimals="INF"
      id="ixv-497208"
      unitRef="pure">0.026</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088100_GD_DE_Member"
      decimals="INF"
      id="ixv-497209"
      unitRef="pure">0.020</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088100_GD_JP_Member"
      decimals="INF"
      id="ixv-497210"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088100_GD_CH_Member"
      decimals="INF"
      id="ixv-497211"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088100_GD_NL_Member"
      decimals="INF"
      id="ixv-497212"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088100_GD_FR_Member"
      decimals="INF"
      id="ixv-497213"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088100_GD_Other_Member"
      decimals="INF"
      id="ixv-497214"
      unitRef="pure">0.038</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000088100_ClassMember" id="ixv-6918">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Bonds

9.2


&#160;


JPMorgan Chase &amp; Co

2.6


&#160;


Bank of America Corp

2.3


&#160;


Morgan Stanley

1.8


&#160;


Boeing Co

1.7


&#160;


Broadcom Inc

1.6


&#160;


Wells Fargo &amp; Co

1.5


&#160;


AerCap Ireland Capital DAC / AerCap Global Aviation Trust

1.3


&#160;


PNC Financial Services Group Inc/The

1.1


&#160;


Duke Energy Corp

1.1


&#160;


&#160;

24.2

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000088100_TH_0_Member"
      decimals="INF"
      id="ixv-497215"
      unitRef="pure">0.092</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088100_TH_1_Member"
      decimals="INF"
      id="ixv-497216"
      unitRef="pure">0.026</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088100_TH_2_Member"
      decimals="INF"
      id="ixv-497217"
      unitRef="pure">0.023</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088100_TH_3_Member"
      decimals="INF"
      id="ixv-497218"
      unitRef="pure">0.018</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088100_TH_4_Member"
      decimals="INF"
      id="ixv-497219"
      unitRef="pure">0.017</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088100_TH_5_Member"
      decimals="INF"
      id="ixv-497220"
      unitRef="pure">0.016</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088100_TH_6_Member"
      decimals="INF"
      id="ixv-497221"
      unitRef="pure">0.015</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088100_TH_7_Member"
      decimals="INF"
      id="ixv-497222"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088100_TH_8_Member"
      decimals="INF"
      id="ixv-497223"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088100_TH_9_Member"
      decimals="INF"
      id="ixv-497224"
      unitRef="pure">0.011</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-7089">2025-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000088096_ClassMember" id="ixv-7101">Fidelity&#xae; Corporate Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000088096_ClassMember" id="ixv-7104">Fidelity&#xae; Corporate Bond Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000088096_ClassMember" id="ixv-7108">FCBFX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000088096_ClassMember" id="ixv-7127">This annual shareholder report contains information about Fidelity&#xae; Corporate Bond Fund for the period September 1, 2024 to August 31, 2025.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000088096_ClassMember" id="ixv-7129">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000088096_ClassMember" id="ixv-7134">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-7136">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000088096_ClassMember" id="ixv-7139">1-800-544-8544</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000088096_ClassMember" id="ixv-7142">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000088096_ClassMember" id="ixv-7149">&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;text-align-last:auto;"&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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:45%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Corporate Bond Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:24%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;46&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;text-align-last:auto;"&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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000088096_ClassMember"
      decimals="0"
      id="ixv-497225"
      unitRef="usd">46</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000088096_ClassMember"
      decimals="INF"
      id="ixv-497226"
      unitRef="pure">0.0045</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000088096_ClassMember" id="ixv-7191">&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;text-align-last:auto;"&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-align-last:auto;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 solid advance for the 12 months ending August 31, 2025, navigating tariff-related uncertainty since late 2024 but buoyed by relatively stable consumer inflation, a resilient economy and the expectation of policy interest-rate cuts by the U.S. Federal Reserve in the second half of 2025.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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 Bloomberg U.S. Credit Bond Index for the fiscal year, whereas sector positioning detracted.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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 companies in the industrials sector helped most, led by issuers in the communications, consumer non-cyclicals and capital goods industries.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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 communications, notable contributors included Warner Bros. Discovery and Charter Communications. In consumer non-cyclicals, pharmaceutical company Bayer was a standout, while Boeing drove the contribution in capital goods.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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 financial issuers also notably aided relative performance. Here, bonds from banks, real estate investment trusts and insurance companies helped most.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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. Treasurys and cash - held for liquidity and risk-management purposes - meaningfully detracted from the fund's relative result. This negative was somewhat offset by steering clear of 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;text-align-last:auto;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 yield curve strategy of concentrating the portfolio's holdings in the five- to seven-year portion of the curve had a neutral impact on relative performance.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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;During the period, the fund's managers continued to emphasize issuers rated BBB, as they believe there is opportunity for alpha potential over time resulting from improving credit quality. They modestly added bonds rated A, in response to tight spreads and uncertainty.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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;Noteworthy positioning changes included reducing exposure to non-bank financials (e.g., finance companies) and redeploying the capital into industrials and utilities.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000088096_ClassMember" id="ixv-7224">How did the Fund perform over the past 10 years?

 &#160;&#160;
CUMULATIVE PERFORMANCE
August 31, 2015 through August 31, 2025.
Initial investment of $10,000.
Fidelity&#xae; Corporate Bond Fund


$10,000

$10,914


$11,216


$11,145


$12,606


$13,629


$13,978


$11,806


$11,928


$13,108


$13,629



Bloomberg U.S. Credit Bond Index


$10,000

$10,914


$11,122


$11,012


$12,443


$13,326


$13,627


$11,661


$11,759


$12,816


$13,318



Bloomberg U.S. Aggregate Bond Index


$10,000

$10,597


$10,649


$10,537


$11,609


$12,360


$12,350


$10,928


$10,797


$11,585


$11,949



&#160;

2015

2016

2017

2018

2019

2020

2021

2022

2023

2024

2025









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000088096_LG_ClassMember_11YR" id="ixv-7243">&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:AccmVal
      contextRef="C000088096_ClassMember_AsOf_2015"
      decimals="0"
      id="ixv-497227"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088096_ClassMember_AsOf_2016"
      decimals="0"
      id="ixv-497228"
      unitRef="usd">10914</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088096_ClassMember_AsOf_2017"
      decimals="0"
      id="ixv-497229"
      unitRef="usd">11216</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088096_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-497230"
      unitRef="usd">11145</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088096_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-497231"
      unitRef="usd">12606</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088096_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-497232"
      unitRef="usd">13629</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088096_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-497233"
      unitRef="usd">13978</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088096_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-497234"
      unitRef="usd">11806</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088096_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-497235"
      unitRef="usd">11928</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088096_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-497236"
      unitRef="usd">13108</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088096_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-497237"
      unitRef="usd">13629</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000088096_LG_1_AdditionalIndexMember_11YR"
      id="ixv-7292">&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:AccmVal
      contextRef="C000088096_1_AdditionalIndexMember_AsOf_2015"
      decimals="0"
      id="ixv-497238"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088096_1_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-497239"
      unitRef="usd">10914</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088096_1_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-497240"
      unitRef="usd">11122</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088096_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-497241"
      unitRef="usd">11012</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088096_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-497242"
      unitRef="usd">12443</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088096_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-497243"
      unitRef="usd">13326</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088096_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-497244"
      unitRef="usd">13627</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088096_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-497245"
      unitRef="usd">11661</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088096_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-497246"
      unitRef="usd">11759</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088096_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-497247"
      unitRef="usd">12816</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088096_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-497248"
      unitRef="usd">13318</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000088096_LG_2_AdditionalIndexMember_11YR"
      id="ixv-7341">&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:AccmVal
      contextRef="C000088096_2_AdditionalIndexMember_AsOf_2015"
      decimals="0"
      id="ixv-497249"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088096_2_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-497250"
      unitRef="usd">10597</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088096_2_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-497251"
      unitRef="usd">10649</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088096_2_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-497252"
      unitRef="usd">10537</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088096_2_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-497253"
      unitRef="usd">11609</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088096_2_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-497254"
      unitRef="usd">12360</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088096_2_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-497255"
      unitRef="usd">12350</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088096_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-497256"
      unitRef="usd">10928</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088096_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-497257"
      unitRef="usd">10797</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088096_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-497258"
      unitRef="usd">11585</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088096_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-497259"
      unitRef="usd">11949</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000088096_ClassMember" id="ixv-7442">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

10 Year


Fidelity&#xae; Corporate Bond Fund

3.97%

0.00%

3.14%


Bloomberg U.S. Credit Bond Index

3.92%


-0.01%


2.91%


Bloomberg U.S. Aggregate Bond Index

3.14%


-0.68%


1.80%




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

&#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.





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
      contextRef="C000088096_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-497260"
      unitRef="pure">0.0397</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088096_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-497261"
      unitRef="pure">0.0000</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088096_NoLoadClassMember_10YR"
      decimals="INF"
      id="ixv-497262"
      unitRef="pure">0.0314</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088096_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-497263"
      unitRef="pure">0.0392</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088096_0_AdditionalIndexMember_5YR"
      decimals="INF"
      id="ixv-497264"
      unitRef="pure">-0.0001</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088096_0_AdditionalIndexMember_10YR"
      decimals="INF"
      id="ixv-497265"
      unitRef="pure">0.0291</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088096_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-497266"
      unitRef="pure">0.0314</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088096_1_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-497267"
      unitRef="pure">-0.0068</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088096_1_BBIndexMember_10YR"
      decimals="INF"
      id="ixv-497268"
      unitRef="pure">0.0180</oef:AvgAnnlRtrPct>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000088096_ClassMember" id="ixv-7514">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Visit &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;www.fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; for more recent performance information.&lt;/span&gt;</oef:UpdPerfInfoLocationTextBlock>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000088096_ClassMember" id="ixv-7526">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:italic;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-7530">&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-7536">&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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2025)&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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&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;text-align-last:auto;"&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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&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;div style="text-align:left;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;2,081,012,659&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;600&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;7,046,841&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;div style="text-align:right;text-align-last:auto;"&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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
    <us-gaap:AssetsNet
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&#160;
U.S. Government and U.S. Government Agency Obligations

9.2


AAA

0.1


AA

0.0


A

23.1


BBB

57.0


BB

4.9


B

1.3


Not Rated

0.1


Short-Term Investments and Net Other Assets (Liabilities)

4.3




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 9.2


&#160;

AAA - 0.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

AA - 0.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 23.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 57.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BB - 4.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

B - 1.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Not Rated - 0.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 4.3


&#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;
&#160;
&#160;
Corporate Bonds

85.3


U.S. Treasury Obligations

9.2


Asset-Backed Securities

0.6


Preferred Securities

0.3


Foreign Government and Government Agency Obligations

0.1


CMOs and Other Mortgage Related Securities

0.1


Other Investments

0.1


Municipal Securities

0.0


Short-Term Investments and Net Other Assets (Liabilities)

4.3




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

Corporate Bonds - 85.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Treasury Obligations - 9.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Asset-Backed Securities - 0.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Preferred Securities - 0.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Foreign Government and Government Agency Obligations - 0.1


&#160;

CMOs and Other Mortgage Related Securities - 0.1


&#160;

Other Investments - 0.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Municipal Securities - 0.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 4.3


&#160;






United States

80.5


Canada

3.5


United Kingdom

3.3


Ireland

2.6


Germany

2.0


Japan

1.3


Switzerland

1.1


Netherlands

1.0


France

0.9


Others

3.8




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 80.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 3.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 3.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Ireland - 2.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 2.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Japan - 1.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Switzerland - 1.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Netherlands - 1.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

France - 0.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 3.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
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    <oef:LargestHoldingsTableTextBlock contextRef="C000088096_ClassMember" id="ixv-8072">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Bonds

9.2


&#160;


JPMorgan Chase &amp; Co

2.6


&#160;


Bank of America Corp

2.3


&#160;


Morgan Stanley

1.8


&#160;


Boeing Co

1.7


&#160;


Broadcom Inc

1.6


&#160;


Wells Fargo &amp; Co

1.5


&#160;


AerCap Ireland Capital DAC / AerCap Global Aviation Trust

1.3


&#160;


PNC Financial Services Group Inc/The

1.1


&#160;


Duke Energy Corp

1.1


&#160;


&#160;

24.2

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-497301"
      unitRef="pure">0.092</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
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      unitRef="pure">0.026</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-497303"
      unitRef="pure">0.023</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-497304"
      unitRef="pure">0.018</oef:PctOfNav>
    <oef:PctOfNav
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      unitRef="pure">0.017</oef:PctOfNav>
    <oef:PctOfNav
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    <oef:PctOfNav
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      id="ixv-497309"
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    <oef:PctOfNav
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      decimals="INF"
      id="ixv-497310"
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    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-8243">2025-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000088099_ClassMember" id="ixv-8255">Fidelity&#xae; Corporate Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000088099_ClassMember" id="ixv-8258">Fidelity Advisor&#xae; Corporate Bond Fund Class C</oef:ClassName>
    <dei:TradingSymbol contextRef="C000088099_ClassMember" id="ixv-8262">FCCCX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000088099_ClassMember" id="ixv-8281">This annual shareholder report contains information about Fidelity&#xae; Corporate Bond Fund for the period September 1, 2024 to August 31, 2025.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000088099_ClassMember" id="ixv-8283">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000088099_ClassMember" id="ixv-8288">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-8290">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000088099_ClassMember" id="ixv-8293">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000088099_ClassMember" id="ixv-8296">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000088099_ClassMember" id="ixv-8303">&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;text-align-last:auto;"&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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:45%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class C&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:24%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;155&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;text-align-last:auto;"&gt;1.52&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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000088099_ClassMember"
      decimals="0"
      id="ixv-497311"
      unitRef="usd">155</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000088099_ClassMember"
      decimals="INF"
      id="ixv-497312"
      unitRef="pure">0.0152</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000088099_ClassMember" id="ixv-8345">&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;text-align-last:auto;"&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-align-last:auto;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 solid advance for the 12 months ending August 31, 2025, navigating tariff-related uncertainty since late 2024 but buoyed by relatively stable consumer inflation, a resilient economy and the expectation of policy interest-rate cuts by the U.S. Federal Reserve in the second half of 2025.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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 Bloomberg U.S. Credit Bond Index for the fiscal year, whereas sector positioning detracted.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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 companies in the industrials sector helped most, led by issuers in the communications, consumer non-cyclicals and capital goods industries.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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 communications, notable contributors included Warner Bros. Discovery and Charter Communications. In consumer non-cyclicals, pharmaceutical company Bayer was a standout, while Boeing drove the contribution in capital goods.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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 financial issuers also notably aided relative performance. Here, bonds from banks, real estate investment trusts and insurance companies helped most.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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. Treasurys and cash - held for liquidity and risk-management purposes - meaningfully detracted from the fund's relative result. This negative was somewhat offset by steering clear of 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;text-align-last:auto;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 yield curve strategy of concentrating the portfolio's holdings in the five- to seven-year portion of the curve had a neutral impact on relative performance.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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;During the period, the fund's managers continued to emphasize issuers rated BBB, as they believe there is opportunity for alpha potential over time resulting from improving credit quality. They modestly added bonds rated A, in response to tight spreads and uncertainty.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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;Noteworthy positioning changes included reducing exposure to non-bank financials (e.g., finance companies) and redeploying the capital into industrials and utilities.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000088099_ClassMember" id="ixv-8378">How did the Fund perform over the past 10 years?

 &#160;&#160;
CUMULATIVE PERFORMANCE
August 31, 2015 through August 31, 2025.
Initial investment of $10,000.
Class C


$10,000

$10,786


$10,975


$10,786


$12,057


$12,906


$13,094


$10,939


$10,932


$11,974


$12,410



Bloomberg U.S. Credit Bond Index


$10,000

$10,914


$11,122


$11,012


$12,443


$13,326


$13,627


$11,661


$11,759


$12,816


$13,318



Bloomberg U.S. Aggregate Bond Index


$10,000

$10,597


$10,649


$10,537


$11,609


$12,360


$12,350


$10,928


$10,797


$11,585


$11,949



&#160;

2015

2016

2017

2018

2019

2020

2021

2022

2023

2024

2025









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000088099_LG_ClassMember_11YR" id="ixv-8397">&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:AccmVal
      contextRef="C000088099_ClassMember_AsOf_2015"
      decimals="0"
      id="ixv-497313"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088099_ClassMember_AsOf_2016"
      decimals="0"
      id="ixv-497314"
      unitRef="usd">10786</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088099_ClassMember_AsOf_2017"
      decimals="0"
      id="ixv-497315"
      unitRef="usd">10975</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088099_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-497316"
      unitRef="usd">10786</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088099_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-497317"
      unitRef="usd">12057</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088099_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-497318"
      unitRef="usd">12906</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088099_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-497319"
      unitRef="usd">13094</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088099_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-497320"
      unitRef="usd">10939</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088099_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-497321"
      unitRef="usd">10932</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088099_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-497322"
      unitRef="usd">11974</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088099_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-497323"
      unitRef="usd">12410</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000088099_LG_1_AdditionalIndexMember_11YR"
      id="ixv-8446">&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:AccmVal
      contextRef="C000088099_1_AdditionalIndexMember_AsOf_2015"
      decimals="0"
      id="ixv-497324"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088099_1_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-497325"
      unitRef="usd">10914</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088099_1_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-497326"
      unitRef="usd">11122</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088099_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-497327"
      unitRef="usd">11012</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088099_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-497328"
      unitRef="usd">12443</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088099_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-497329"
      unitRef="usd">13326</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088099_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-497330"
      unitRef="usd">13627</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088099_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-497331"
      unitRef="usd">11661</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088099_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-497332"
      unitRef="usd">11759</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088099_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-497333"
      unitRef="usd">12816</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088099_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-497334"
      unitRef="usd">13318</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000088099_LG_2_AdditionalIndexMember_11YR"
      id="ixv-8495">&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:AccmVal
      contextRef="C000088099_2_AdditionalIndexMember_AsOf_2015"
      decimals="0"
      id="ixv-497335"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088099_2_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-497336"
      unitRef="usd">10597</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088099_2_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-497337"
      unitRef="usd">10649</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088099_2_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-497338"
      unitRef="usd">10537</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088099_2_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-497339"
      unitRef="usd">11609</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088099_2_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-497340"
      unitRef="usd">12360</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088099_2_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-497341"
      unitRef="usd">12350</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088099_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-497342"
      unitRef="usd">10928</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088099_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-497343"
      unitRef="usd">10797</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088099_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-497344"
      unitRef="usd">11585</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088099_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-497345"
      unitRef="usd">11949</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000088099_ClassMember" id="ixv-8596">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

10 Year


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

1.87%

-1.08%


2.18%


Class C

2.87%

-1.08%

2.18%


Bloomberg U.S. Credit Bond Index

3.92%


-0.01%


2.91%


Bloomberg U.S. Aggregate Bond Index

3.14%


-0.68%


1.80%




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

&#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.





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
      contextRef="C000088099_ClassMember_1YR"
      decimals="INF"
      id="ixv-497346"
      unitRef="pure">0.0187</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088099_ClassMember_5YR"
      decimals="INF"
      id="ixv-497347"
      unitRef="pure">-0.0108</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088099_ClassMember_10YR"
      decimals="INF"
      id="ixv-497348"
      unitRef="pure">0.0218</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088099_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-497349"
      unitRef="pure">0.0287</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088099_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-497350"
      unitRef="pure">-0.0108</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088099_NoLoadClassMember_10YR"
      decimals="INF"
      id="ixv-497351"
      unitRef="pure">0.0218</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088099_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-497352"
      unitRef="pure">0.0392</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088099_0_AdditionalIndexMember_5YR"
      decimals="INF"
      id="ixv-497353"
      unitRef="pure">-0.0001</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088099_0_AdditionalIndexMember_10YR"
      decimals="INF"
      id="ixv-497354"
      unitRef="pure">0.0291</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088099_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-497355"
      unitRef="pure">0.0314</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088099_1_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-497356"
      unitRef="pure">-0.0068</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088099_1_BBIndexMember_10YR"
      decimals="INF"
      id="ixv-497357"
      unitRef="pure">0.0180</oef:AvgAnnlRtrPct>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000088099_ClassMember" id="ixv-8686">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Visit &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;institutional.fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; for more recent performance information.&lt;/span&gt;</oef:UpdPerfInfoLocationTextBlock>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000088099_ClassMember" id="ixv-8698">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:italic;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-8702">&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-8708">&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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2025)&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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&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;text-align-last:auto;"&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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&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;div style="text-align:left;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;2,081,012,659&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;600&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;7,046,841&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;div style="text-align:right;text-align-last:auto;"&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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
    <us-gaap:AssetsNet
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&#160;
U.S. Government and U.S. Government Agency Obligations

9.2


AAA

0.1


AA

0.0


A

23.1


BBB

57.0


BB

4.9


B

1.3


Not Rated

0.1


Short-Term Investments and Net Other Assets (Liabilities)

4.3




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 9.2


&#160;

AAA - 0.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

AA - 0.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 23.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 57.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BB - 4.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

B - 1.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Not Rated - 0.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 4.3


&#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;
&#160;
&#160;
Corporate Bonds

85.3


U.S. Treasury Obligations

9.2


Asset-Backed Securities

0.6


Preferred Securities

0.3


Foreign Government and Government Agency Obligations

0.1


CMOs and Other Mortgage Related Securities

0.1


Other Investments

0.1


Municipal Securities

0.0


Short-Term Investments and Net Other Assets (Liabilities)

4.3




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

Corporate Bonds - 85.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Treasury Obligations - 9.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Asset-Backed Securities - 0.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Preferred Securities - 0.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Foreign Government and Government Agency Obligations - 0.1


&#160;

CMOs and Other Mortgage Related Securities - 0.1


&#160;

Other Investments - 0.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Municipal Securities - 0.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 4.3


&#160;






United States

80.5


Canada

3.5


United Kingdom

3.3


Ireland

2.6


Germany

2.0


Japan

1.3


Switzerland

1.1


Netherlands

1.0


France

0.9


Others

3.8




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 80.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 3.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 3.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Ireland - 2.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 2.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Japan - 1.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Switzerland - 1.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Netherlands - 1.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

France - 0.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 3.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
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    <oef:PctOfNav
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    <oef:PctOfNav
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      unitRef="pure">0.020</oef:PctOfNav>
    <oef:PctOfNav
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      id="ixv-497385"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088099_GD_CH_Member"
      decimals="INF"
      id="ixv-497386"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088099_GD_NL_Member"
      decimals="INF"
      id="ixv-497387"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-497388"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:PctOfNav
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      id="ixv-497389"
      unitRef="pure">0.038</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000088099_ClassMember" id="ixv-9244">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Bonds

9.2


&#160;


JPMorgan Chase &amp; Co

2.6


&#160;


Bank of America Corp

2.3


&#160;


Morgan Stanley

1.8


&#160;


Boeing Co

1.7


&#160;


Broadcom Inc

1.6


&#160;


Wells Fargo &amp; Co

1.5


&#160;


AerCap Ireland Capital DAC / AerCap Global Aviation Trust

1.3


&#160;


PNC Financial Services Group Inc/The

1.1


&#160;


Duke Energy Corp

1.1


&#160;


&#160;

24.2

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-497390"
      unitRef="pure">0.092</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-497391"
      unitRef="pure">0.026</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088099_TH_2_Member"
      decimals="INF"
      id="ixv-497392"
      unitRef="pure">0.023</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088099_TH_3_Member"
      decimals="INF"
      id="ixv-497393"
      unitRef="pure">0.018</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088099_TH_4_Member"
      decimals="INF"
      id="ixv-497394"
      unitRef="pure">0.017</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088099_TH_5_Member"
      decimals="INF"
      id="ixv-497395"
      unitRef="pure">0.016</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-497396"
      unitRef="pure">0.015</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-497397"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088099_TH_8_Member"
      decimals="INF"
      id="ixv-497398"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-497399"
      unitRef="pure">0.011</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-9415">2025-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000205023_ClassMember" id="ixv-9427">Fidelity&#xae; Corporate Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000205023_ClassMember" id="ixv-9430">Fidelity Advisor&#xae; Corporate Bond Fund Class Z</oef:ClassName>
    <dei:TradingSymbol contextRef="C000205023_ClassMember" id="ixv-9434">FIKOX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000205023_ClassMember" id="ixv-9453">This annual shareholder report contains information about Fidelity&#xae; Corporate Bond Fund for the period September 1, 2024 to August 31, 2025.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000205023_ClassMember" id="ixv-9455">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000205023_ClassMember" id="ixv-9460">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-9462">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000205023_ClassMember" id="ixv-9465">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000205023_ClassMember" id="ixv-9468">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000205023_ClassMember" id="ixv-9475">&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;text-align-last:auto;"&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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:45%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class Z&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:24%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;37&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;text-align-last:auto;"&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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000205023_ClassMember"
      decimals="0"
      id="ixv-497400"
      unitRef="usd">37</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000205023_ClassMember"
      decimals="INF"
      id="ixv-497401"
      unitRef="pure">0.0036</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000205023_ClassMember" id="ixv-9517">&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;text-align-last:auto;"&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-align-last:auto;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 solid advance for the 12 months ending August 31, 2025, navigating tariff-related uncertainty since late 2024 but buoyed by relatively stable consumer inflation, a resilient economy and the expectation of policy interest-rate cuts by the U.S. Federal Reserve in the second half of 2025.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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 Bloomberg U.S. Credit Bond Index for the fiscal year, whereas sector positioning detracted.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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 companies in the industrials sector helped most, led by issuers in the communications, consumer non-cyclicals and capital goods industries.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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 communications, notable contributors included Warner Bros. Discovery and Charter Communications. In consumer non-cyclicals, pharmaceutical company Bayer was a standout, while Boeing drove the contribution in capital goods.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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 financial issuers also notably aided relative performance. Here, bonds from banks, real estate investment trusts and insurance companies helped most.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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. Treasurys and cash - held for liquidity and risk-management purposes - meaningfully detracted from the fund's relative result. This negative was somewhat offset by steering clear of 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;text-align-last:auto;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 yield curve strategy of concentrating the portfolio's holdings in the five- to seven-year portion of the curve had a neutral impact on relative performance.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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;During the period, the fund's managers continued to emphasize issuers rated BBB, as they believe there is opportunity for alpha potential over time resulting from improving credit quality. They modestly added bonds rated A, in response to tight spreads and uncertainty.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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;Noteworthy positioning changes included reducing exposure to non-bank financials (e.g., finance companies) and redeploying the capital into industrials and utilities.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000205023_ClassMember" id="ixv-9550">How did the Fund perform over the life of Fund?

 &#160;&#160;
CUMULATIVE PERFORMANCE
October 2, 2018 through August 31, 2025.
Initial investment of $10,000.
Class Z


$10,000

$11,334


$12,275


$12,601


$10,652


$10,761


$11,847


$12,329



Bloomberg U.S. Credit Bond Index


$10,000

$11,331


$12,135


$12,409


$10,618


$10,708


$11,670


$12,128



Bloomberg U.S. Aggregate Bond Index


$10,000

$11,086


$11,804


$11,794


$10,436


$10,311


$11,064


$11,411



&#160;

2018

2019

2020

2021

2022

2023

2024

2025









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000205023_LG_ClassMember_8YR" id="ixv-9569">&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:AccmVal
      contextRef="C000205023_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-497402"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205023_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-497403"
      unitRef="usd">11334</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205023_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-497404"
      unitRef="usd">12275</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205023_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-497405"
      unitRef="usd">12601</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205023_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-497406"
      unitRef="usd">10652</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205023_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-497407"
      unitRef="usd">10761</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205023_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-497408"
      unitRef="usd">11847</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205023_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-497409"
      unitRef="usd">12329</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000205023_LG_1_AdditionalIndexMember_8YR"
      id="ixv-9606">&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:AccmVal
      contextRef="C000205023_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-497410"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205023_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-497411"
      unitRef="usd">11331</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205023_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-497412"
      unitRef="usd">12135</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205023_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-497413"
      unitRef="usd">12409</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205023_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-497414"
      unitRef="usd">10618</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205023_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-497415"
      unitRef="usd">10708</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205023_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-497416"
      unitRef="usd">11670</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205023_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-497417"
      unitRef="usd">12128</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000205023_LG_2_AdditionalIndexMember_8YR"
      id="ixv-9643">&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:AccmVal
      contextRef="C000205023_2_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-497418"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205023_2_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-497419"
      unitRef="usd">11086</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205023_2_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-497420"
      unitRef="usd">11804</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205023_2_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-497421"
      unitRef="usd">11794</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205023_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-497422"
      unitRef="usd">10436</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205023_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-497423"
      unitRef="usd">10311</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205023_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-497424"
      unitRef="usd">11064</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000205023_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-497425"
      unitRef="usd">11411</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000205023_ClassMember" id="ixv-9723">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

Life of Fund&#160;A


Class Z

4.07%

0.09%

3.07%


Bloomberg U.S. Credit Bond Index

3.92%


-0.01%


2.83%


Bloomberg U.S. Aggregate Bond Index

3.14%


-0.68%


1.93%




A&#160; &#160;From October 2, 2018

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

&#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.





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
      contextRef="C000205023_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-497426"
      unitRef="pure">0.0407</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000205023_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-497427"
      unitRef="pure">0.0009</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000205023_NoLoadClassMember_2024-09-01_2025-08-31"
      decimals="INF"
      id="ixv-497428"
      unitRef="pure">0.0307</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000205023_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-497429"
      unitRef="pure">0.0392</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000205023_0_AdditionalIndexMember_5YR"
      decimals="INF"
      id="ixv-497430"
      unitRef="pure">-0.0001</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000205023_0_AdditionalIndexMember_LOC"
      decimals="INF"
      id="ixv-497431"
      unitRef="pure">0.0283</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000205023_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-497432"
      unitRef="pure">0.0314</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000205023_1_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-497433"
      unitRef="pure">-0.0068</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000205023_1_BBIndexMember_LOC"
      decimals="INF"
      id="ixv-497434"
      unitRef="pure">0.0193</oef:AvgAnnlRtrPct>
    <oef:PerfInceptionDate
      contextRef="C000205023_Perf_2018-10-02_ClassMember"
      id="ixv-9794">2018-10-02</oef:PerfInceptionDate>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000205023_ClassMember" id="ixv-9804">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Visit &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;institutional.fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; for more recent performance information.&lt;/span&gt;</oef:UpdPerfInfoLocationTextBlock>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000205023_ClassMember" id="ixv-9816">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:italic;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-9820">&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-9826">&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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2025)&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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&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;text-align-last:auto;"&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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&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;div style="text-align:left;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;2,081,012,659&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;600&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;7,046,841&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;div style="text-align:right;text-align-last:auto;"&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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
    <us-gaap:AssetsNet
      contextRef="C000205023_InstantMember"
      decimals="0"
      id="ixv-497435"
      unitRef="usd">2081012659</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000205023_InstantMember"
      decimals="INF"
      id="ixv-497436"
      unitRef="holding">600</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000205023_ClassMember"
      decimals="0"
      id="ixv-497437"
      unitRef="usd">7046841</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000205023_ClassMember"
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    <oef:HoldingsTableTextBlock contextRef="C000205023_ClassMember" id="ixv-9901">
&#160;
U.S. Government and U.S. Government Agency Obligations

9.2


AAA

0.1


AA

0.0


A

23.1


BBB

57.0


BB

4.9


B

1.3


Not Rated

0.1


Short-Term Investments and Net Other Assets (Liabilities)

4.3




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 9.2


&#160;

AAA - 0.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

AA - 0.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 23.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 57.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BB - 4.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

B - 1.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Not Rated - 0.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 4.3


&#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;
&#160;
&#160;
Corporate Bonds

85.3


U.S. Treasury Obligations

9.2


Asset-Backed Securities

0.6


Preferred Securities

0.3


Foreign Government and Government Agency Obligations

0.1


CMOs and Other Mortgage Related Securities

0.1


Other Investments

0.1


Municipal Securities

0.0


Short-Term Investments and Net Other Assets (Liabilities)

4.3




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

Corporate Bonds - 85.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Treasury Obligations - 9.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Asset-Backed Securities - 0.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Preferred Securities - 0.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Foreign Government and Government Agency Obligations - 0.1


&#160;

CMOs and Other Mortgage Related Securities - 0.1


&#160;

Other Investments - 0.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Municipal Securities - 0.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 4.3


&#160;






United States

80.5


Canada

3.5


United Kingdom

3.3


Ireland

2.6


Germany

2.0


Japan

1.3


Switzerland

1.1


Netherlands

1.0


France

0.9


Others

3.8




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 80.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 3.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 3.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Ireland - 2.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 2.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Japan - 1.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Switzerland - 1.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Netherlands - 1.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

France - 0.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 3.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
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      id="ixv-497448"
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      id="ixv-497451"
      unitRef="pure">0.003</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-497452"
      unitRef="pure">0.001</oef:PctOfNav>
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      id="ixv-497453"
      unitRef="pure">0.001</oef:PctOfNav>
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      id="ixv-497456"
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      decimals="INF"
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      unitRef="pure">0.805</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-497458"
      unitRef="pure">0.035</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-497459"
      unitRef="pure">0.033</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-497460"
      unitRef="pure">0.026</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-497461"
      unitRef="pure">0.020</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-497462"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205023_GD_CH_Member"
      decimals="INF"
      id="ixv-497463"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205023_GD_NL_Member"
      decimals="INF"
      id="ixv-497464"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205023_GD_FR_Member"
      decimals="INF"
      id="ixv-497465"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205023_GD_Other_Member"
      decimals="INF"
      id="ixv-497466"
      unitRef="pure">0.038</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000205023_ClassMember" id="ixv-10362">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Bonds

9.2


&#160;


JPMorgan Chase &amp; Co

2.6


&#160;


Bank of America Corp

2.3


&#160;


Morgan Stanley

1.8


&#160;


Boeing Co

1.7


&#160;


Broadcom Inc

1.6


&#160;


Wells Fargo &amp; Co

1.5


&#160;


AerCap Ireland Capital DAC / AerCap Global Aviation Trust

1.3


&#160;


PNC Financial Services Group Inc/The

1.1


&#160;


Duke Energy Corp

1.1


&#160;


&#160;

24.2

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000205023_TH_0_Member"
      decimals="INF"
      id="ixv-497467"
      unitRef="pure">0.092</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205023_TH_1_Member"
      decimals="INF"
      id="ixv-497468"
      unitRef="pure">0.026</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205023_TH_2_Member"
      decimals="INF"
      id="ixv-497469"
      unitRef="pure">0.023</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205023_TH_3_Member"
      decimals="INF"
      id="ixv-497470"
      unitRef="pure">0.018</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205023_TH_4_Member"
      decimals="INF"
      id="ixv-497471"
      unitRef="pure">0.017</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205023_TH_5_Member"
      decimals="INF"
      id="ixv-497472"
      unitRef="pure">0.016</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205023_TH_6_Member"
      decimals="INF"
      id="ixv-497473"
      unitRef="pure">0.015</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205023_TH_7_Member"
      decimals="INF"
      id="ixv-497474"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205023_TH_8_Member"
      decimals="INF"
      id="ixv-497475"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000205023_TH_9_Member"
      decimals="INF"
      id="ixv-497476"
      unitRef="pure">0.011</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-10533">2025-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000088101_ClassMember" id="ixv-10545">Fidelity&#xae; Corporate Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000088101_ClassMember" id="ixv-10548">Fidelity Advisor&#xae; Corporate Bond Fund Class I</oef:ClassName>
    <dei:TradingSymbol contextRef="C000088101_ClassMember" id="ixv-10552">FCBIX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000088101_ClassMember" id="ixv-10571">This annual shareholder report contains information about Fidelity&#xae; Corporate Bond Fund for the period September 1, 2024 to August 31, 2025.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000088101_ClassMember" id="ixv-10573">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000088101_ClassMember" id="ixv-10578">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-10580">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000088101_ClassMember" id="ixv-10583">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000088101_ClassMember" id="ixv-10586">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000088101_ClassMember" id="ixv-10593">&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;text-align-last:auto;"&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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:45%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class I&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:24%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;51&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;text-align-last:auto;"&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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000088101_ClassMember"
      decimals="0"
      id="ixv-497477"
      unitRef="usd">51</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000088101_ClassMember"
      decimals="INF"
      id="ixv-497478"
      unitRef="pure">0.0050</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000088101_ClassMember" id="ixv-10635">&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;text-align-last:auto;"&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-align-last:auto;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 solid advance for the 12 months ending August 31, 2025, navigating tariff-related uncertainty since late 2024 but buoyed by relatively stable consumer inflation, a resilient economy and the expectation of policy interest-rate cuts by the U.S. Federal Reserve in the second half of 2025.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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 Bloomberg U.S. Credit Bond Index for the fiscal year, whereas sector positioning detracted.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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 companies in the industrials sector helped most, led by issuers in the communications, consumer non-cyclicals and capital goods industries.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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 communications, notable contributors included Warner Bros. Discovery and Charter Communications. In consumer non-cyclicals, pharmaceutical company Bayer was a standout, while Boeing drove the contribution in capital goods.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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 financial issuers also notably aided relative performance. Here, bonds from banks, real estate investment trusts and insurance companies helped most.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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. Treasurys and cash - held for liquidity and risk-management purposes - meaningfully detracted from the fund's relative result. This negative was somewhat offset by steering clear of 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;text-align-last:auto;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 yield curve strategy of concentrating the portfolio's holdings in the five- to seven-year portion of the curve had a neutral impact on relative performance.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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;During the period, the fund's managers continued to emphasize issuers rated BBB, as they believe there is opportunity for alpha potential over time resulting from improving credit quality. They modestly added bonds rated A, in response to tight spreads and uncertainty.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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;Noteworthy positioning changes included reducing exposure to non-bank financials (e.g., finance companies) and redeploying the capital into industrials and utilities.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000088101_ClassMember" id="ixv-10668">How did the Fund perform over the past 10 years?

 &#160;&#160;
CUMULATIVE PERFORMANCE
August 31, 2015 through August 31, 2025.
Initial investment of $10,000.
Class I


$10,000

$10,908


$11,205


$11,129


$12,582


$13,597


$13,938


$11,767


$11,882


$13,052


$13,563



Bloomberg U.S. Credit Bond Index


$10,000

$10,914


$11,122


$11,012


$12,443


$13,326


$13,627


$11,661


$11,759


$12,816


$13,318



Bloomberg U.S. Aggregate Bond Index


$10,000

$10,597


$10,649


$10,537


$11,609


$12,360


$12,350


$10,928


$10,797


$11,585


$11,949



&#160;

2015

2016

2017

2018

2019

2020

2021

2022

2023

2024

2025









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000088101_LG_ClassMember_11YR" id="ixv-10687">&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:AccmVal
      contextRef="C000088101_ClassMember_AsOf_2015"
      decimals="0"
      id="ixv-497479"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088101_ClassMember_AsOf_2016"
      decimals="0"
      id="ixv-497480"
      unitRef="usd">10908</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088101_ClassMember_AsOf_2017"
      decimals="0"
      id="ixv-497481"
      unitRef="usd">11205</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088101_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-497482"
      unitRef="usd">11129</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088101_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-497483"
      unitRef="usd">12582</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088101_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-497484"
      unitRef="usd">13597</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088101_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-497485"
      unitRef="usd">13938</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088101_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-497486"
      unitRef="usd">11767</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088101_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-497487"
      unitRef="usd">11882</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088101_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-497488"
      unitRef="usd">13052</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088101_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-497489"
      unitRef="usd">13563</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000088101_LG_1_AdditionalIndexMember_11YR"
      id="ixv-10736">&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:AccmVal
      contextRef="C000088101_1_AdditionalIndexMember_AsOf_2015"
      decimals="0"
      id="ixv-497490"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088101_1_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-497491"
      unitRef="usd">10914</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088101_1_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-497492"
      unitRef="usd">11122</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088101_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-497493"
      unitRef="usd">11012</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088101_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-497494"
      unitRef="usd">12443</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088101_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-497495"
      unitRef="usd">13326</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088101_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-497496"
      unitRef="usd">13627</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088101_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-497497"
      unitRef="usd">11661</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088101_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-497498"
      unitRef="usd">11759</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088101_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-497499"
      unitRef="usd">12816</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088101_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-497500"
      unitRef="usd">13318</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000088101_LG_2_AdditionalIndexMember_11YR"
      id="ixv-10785">&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:AccmVal
      contextRef="C000088101_2_AdditionalIndexMember_AsOf_2015"
      decimals="0"
      id="ixv-497501"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088101_2_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-497502"
      unitRef="usd">10597</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088101_2_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-497503"
      unitRef="usd">10649</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088101_2_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-497504"
      unitRef="usd">10537</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088101_2_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-497505"
      unitRef="usd">11609</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088101_2_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-497506"
      unitRef="usd">12360</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088101_2_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-497507"
      unitRef="usd">12350</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088101_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-497508"
      unitRef="usd">10928</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088101_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-497509"
      unitRef="usd">10797</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088101_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-497510"
      unitRef="usd">11585</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088101_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-497511"
      unitRef="usd">11949</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000088101_ClassMember" id="ixv-10886">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

10 Year


Class I

3.92%

-0.05%

3.09%


Bloomberg U.S. Credit Bond Index

3.92%


-0.01%


2.91%


Bloomberg U.S. Aggregate Bond Index

3.14%


-0.68%


1.80%




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

&#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.





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
      contextRef="C000088101_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-497512"
      unitRef="pure">0.0392</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088101_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-497513"
      unitRef="pure">-0.0005</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088101_NoLoadClassMember_10YR"
      decimals="INF"
      id="ixv-497514"
      unitRef="pure">0.0309</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088101_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-497515"
      unitRef="pure">0.0392</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088101_0_AdditionalIndexMember_5YR"
      decimals="INF"
      id="ixv-497516"
      unitRef="pure">-0.0001</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088101_0_AdditionalIndexMember_10YR"
      decimals="INF"
      id="ixv-497517"
      unitRef="pure">0.0291</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088101_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-497518"
      unitRef="pure">0.0314</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088101_1_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-497519"
      unitRef="pure">-0.0068</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088101_1_BBIndexMember_10YR"
      decimals="INF"
      id="ixv-497520"
      unitRef="pure">0.0180</oef:AvgAnnlRtrPct>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000088101_ClassMember" id="ixv-10959">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Visit &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;institutional.fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; for more recent performance information.&lt;/span&gt;</oef:UpdPerfInfoLocationTextBlock>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000088101_ClassMember" id="ixv-10971">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:italic;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-10975">&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-10981">&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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2025)&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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&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;text-align-last:auto;"&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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&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;div style="text-align:left;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;2,081,012,659&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;600&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;7,046,841&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;div style="text-align:right;text-align-last:auto;"&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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
    <us-gaap:AssetsNet
      contextRef="C000088101_InstantMember"
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&#160;
U.S. Government and U.S. Government Agency Obligations

9.2


AAA

0.1


AA

0.0


A

23.1


BBB

57.0


BB

4.9


B

1.3


Not Rated

0.1


Short-Term Investments and Net Other Assets (Liabilities)

4.3




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 9.2


&#160;

AAA - 0.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

AA - 0.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 23.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 57.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BB - 4.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

B - 1.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Not Rated - 0.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 4.3


&#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;
&#160;
&#160;
Corporate Bonds

85.3


U.S. Treasury Obligations

9.2


Asset-Backed Securities

0.6


Preferred Securities

0.3


Foreign Government and Government Agency Obligations

0.1


CMOs and Other Mortgage Related Securities

0.1


Other Investments

0.1


Municipal Securities

0.0


Short-Term Investments and Net Other Assets (Liabilities)

4.3




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

Corporate Bonds - 85.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Treasury Obligations - 9.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Asset-Backed Securities - 0.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Preferred Securities - 0.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Foreign Government and Government Agency Obligations - 0.1


&#160;

CMOs and Other Mortgage Related Securities - 0.1


&#160;

Other Investments - 0.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Municipal Securities - 0.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 4.3


&#160;






United States

80.5


Canada

3.5


United Kingdom

3.3


Ireland

2.6


Germany

2.0


Japan

1.3


Switzerland

1.1


Netherlands

1.0


France

0.9


Others

3.8




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 80.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 3.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 3.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Ireland - 2.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 2.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Japan - 1.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Switzerland - 1.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Netherlands - 1.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

France - 0.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 3.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
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      id="ixv-497534"
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      id="ixv-497538"
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      id="ixv-497542"
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    <oef:PctOfNav
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      unitRef="pure">0.033</oef:PctOfNav>
    <oef:PctOfNav
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      unitRef="pure">0.026</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
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      unitRef="pure">0.020</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
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    <oef:PctOfNav
      contextRef="C000088101_GD_CH_Member"
      decimals="INF"
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      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-497550"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-497551"
      unitRef="pure">0.009</oef:PctOfNav>
    <oef:PctOfNav
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      decimals="INF"
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      unitRef="pure">0.038</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000088101_ClassMember" id="ixv-11517">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Bonds

9.2


&#160;


JPMorgan Chase &amp; Co

2.6


&#160;


Bank of America Corp

2.3


&#160;


Morgan Stanley

1.8


&#160;


Boeing Co

1.7


&#160;


Broadcom Inc

1.6


&#160;


Wells Fargo &amp; Co

1.5


&#160;


AerCap Ireland Capital DAC / AerCap Global Aviation Trust

1.3


&#160;


PNC Financial Services Group Inc/The

1.1


&#160;


Duke Energy Corp

1.1


&#160;


&#160;

24.2

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-497553"
      unitRef="pure">0.092</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088101_TH_1_Member"
      decimals="INF"
      id="ixv-497554"
      unitRef="pure">0.026</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088101_TH_2_Member"
      decimals="INF"
      id="ixv-497555"
      unitRef="pure">0.023</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088101_TH_3_Member"
      decimals="INF"
      id="ixv-497556"
      unitRef="pure">0.018</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088101_TH_4_Member"
      decimals="INF"
      id="ixv-497557"
      unitRef="pure">0.017</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088101_TH_5_Member"
      decimals="INF"
      id="ixv-497558"
      unitRef="pure">0.016</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088101_TH_6_Member"
      decimals="INF"
      id="ixv-497559"
      unitRef="pure">0.015</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088101_TH_7_Member"
      decimals="INF"
      id="ixv-497560"
      unitRef="pure">0.013</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088101_TH_8_Member"
      decimals="INF"
      id="ixv-497561"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000088101_TH_9_Member"
      decimals="INF"
      id="ixv-497562"
      unitRef="pure">0.011</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-11688">2025-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000088097_ClassMember" id="ixv-11700">Fidelity&#xae; Corporate Bond Fund</oef:FundName>
    <oef:ClassName contextRef="C000088097_ClassMember" id="ixv-11703">Fidelity Advisor&#xae; Corporate Bond Fund Class A</oef:ClassName>
    <dei:TradingSymbol contextRef="C000088097_ClassMember" id="ixv-11707">FCBAX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000088097_ClassMember" id="ixv-11726">This annual shareholder report contains information about Fidelity&#xae; Corporate Bond Fund for the period September 1, 2024 to August 31, 2025.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000088097_ClassMember" id="ixv-11728">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000088097_ClassMember" id="ixv-11733">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-11735">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000088097_ClassMember" id="ixv-11738">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000088097_ClassMember" id="ixv-11741">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000088097_ClassMember" id="ixv-11748">&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;text-align-last:auto;"&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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:45%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Class A&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:24%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;79&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;text-align-last:auto;"&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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
    <oef:ExpensesPaidAmt
      contextRef="C000088097_ClassMember"
      decimals="0"
      id="ixv-497563"
      unitRef="usd">79</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000088097_ClassMember"
      decimals="INF"
      id="ixv-497564"
      unitRef="pure">0.0077</oef:ExpenseRatioPct>
    <oef:FactorsAffectingPerfTextBlock contextRef="C000088097_ClassMember" id="ixv-11790">&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;text-align-last:auto;"&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-align-last:auto;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 solid advance for the 12 months ending August 31, 2025, navigating tariff-related uncertainty since late 2024 but buoyed by relatively stable consumer inflation, a resilient economy and the expectation of policy interest-rate cuts by the U.S. Federal Reserve in the second half of 2025.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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 Bloomberg U.S. Credit Bond Index for the fiscal year, whereas sector positioning detracted.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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 companies in the industrials sector helped most, led by issuers in the communications, consumer non-cyclicals and capital goods industries.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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 communications, notable contributors included Warner Bros. Discovery and Charter Communications. In consumer non-cyclicals, pharmaceutical company Bayer was a standout, while Boeing drove the contribution in capital goods.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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 financial issuers also notably aided relative performance. Here, bonds from banks, real estate investment trusts and insurance companies helped most.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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. Treasurys and cash - held for liquidity and risk-management purposes - meaningfully detracted from the fund's relative result. This negative was somewhat offset by steering clear of 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;text-align-last:auto;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 yield curve strategy of concentrating the portfolio's holdings in the five- to seven-year portion of the curve had a neutral impact on relative performance.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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;During the period, the fund's managers continued to emphasize issuers rated BBB, as they believe there is opportunity for alpha potential over time resulting from improving credit quality. They modestly added bonds rated A, in response to tight spreads and uncertainty.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;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;Noteworthy positioning changes included reducing exposure to non-bank financials (e.g., finance companies) and redeploying the capital into industrials and utilities.&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000088097_ClassMember" id="ixv-11823">How did the Fund perform over the past 10 years?

 &#160;&#160;
CUMULATIVE PERFORMANCE
August 31, 2015 through August 31, 2025.
Initial investment of $10,000&#160;and the current sales charge was paid.
Class A


$9,600

$10,442


$10,695


$10,592


$11,939


$12,868


$13,157


$11,076


$11,154


$12,218


$12,663



Bloomberg U.S. Credit Bond Index


$10,000

$10,914


$11,122


$11,012


$12,443


$13,326


$13,627


$11,661


$11,759


$12,816


$13,318



Bloomberg U.S. Aggregate Bond Index


$10,000

$10,597


$10,649


$10,537


$11,609


$12,360


$12,350


$10,928


$10,797


$11,585


$11,949



&#160;

2015

2016

2017

2018

2019

2020

2021

2022

2023

2024

2025









&#160;
</oef:LineGraphTableTextBlock>
    <oef:LineGraphAndTableMeasureName contextRef="C000088097_LG_ClassMember_11YR" id="ixv-11844">&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:AccmVal
      contextRef="C000088097_ClassMember_AsOf_2015"
      decimals="0"
      id="ixv-497565"
      unitRef="usd">9600</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088097_ClassMember_AsOf_2016"
      decimals="0"
      id="ixv-497566"
      unitRef="usd">10442</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088097_ClassMember_AsOf_2017"
      decimals="0"
      id="ixv-497567"
      unitRef="usd">10695</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088097_ClassMember_AsOf_2018"
      decimals="0"
      id="ixv-497568"
      unitRef="usd">10592</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088097_ClassMember_AsOf_2019"
      decimals="0"
      id="ixv-497569"
      unitRef="usd">11939</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088097_ClassMember_AsOf_2020"
      decimals="0"
      id="ixv-497570"
      unitRef="usd">12868</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088097_ClassMember_AsOf_2021"
      decimals="0"
      id="ixv-497571"
      unitRef="usd">13157</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088097_ClassMember_AsOf_2022"
      decimals="0"
      id="ixv-497572"
      unitRef="usd">11076</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088097_ClassMember_AsOf_2023"
      decimals="0"
      id="ixv-497573"
      unitRef="usd">11154</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088097_ClassMember_AsOf_2024"
      decimals="0"
      id="ixv-497574"
      unitRef="usd">12218</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088097_ClassMember_AsOf_2025"
      decimals="0"
      id="ixv-497575"
      unitRef="usd">12663</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000088097_LG_1_AdditionalIndexMember_11YR"
      id="ixv-11893">&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:AccmVal
      contextRef="C000088097_1_AdditionalIndexMember_AsOf_2015"
      decimals="0"
      id="ixv-497576"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088097_1_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-497577"
      unitRef="usd">10914</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088097_1_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-497578"
      unitRef="usd">11122</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088097_1_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-497579"
      unitRef="usd">11012</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088097_1_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-497580"
      unitRef="usd">12443</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088097_1_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-497581"
      unitRef="usd">13326</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088097_1_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-497582"
      unitRef="usd">13627</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088097_1_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-497583"
      unitRef="usd">11661</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088097_1_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-497584"
      unitRef="usd">11759</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088097_1_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-497585"
      unitRef="usd">12816</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088097_1_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-497586"
      unitRef="usd">13318</oef:AccmVal>
    <oef:LineGraphAndTableMeasureName
      contextRef="C000088097_LG_2_AdditionalIndexMember_11YR"
      id="ixv-11942">&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:AccmVal
      contextRef="C000088097_2_AdditionalIndexMember_AsOf_2015"
      decimals="0"
      id="ixv-497587"
      unitRef="usd">10000</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088097_2_AdditionalIndexMember_AsOf_2016"
      decimals="0"
      id="ixv-497588"
      unitRef="usd">10597</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088097_2_AdditionalIndexMember_AsOf_2017"
      decimals="0"
      id="ixv-497589"
      unitRef="usd">10649</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088097_2_AdditionalIndexMember_AsOf_2018"
      decimals="0"
      id="ixv-497590"
      unitRef="usd">10537</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088097_2_AdditionalIndexMember_AsOf_2019"
      decimals="0"
      id="ixv-497591"
      unitRef="usd">11609</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088097_2_AdditionalIndexMember_AsOf_2020"
      decimals="0"
      id="ixv-497592"
      unitRef="usd">12360</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088097_2_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-497593"
      unitRef="usd">12350</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088097_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-497594"
      unitRef="usd">10928</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088097_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-497595"
      unitRef="usd">10797</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088097_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-497596"
      unitRef="usd">11585</oef:AccmVal>
    <oef:AccmVal
      contextRef="C000088097_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-497597"
      unitRef="usd">11949</oef:AccmVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000088097_ClassMember" id="ixv-12043">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

10 Year


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

-0.50%

-1.13%


2.39%


Class A (without 4.00% sales charge)

3.64%

-0.32%

2.81%


Bloomberg U.S. Credit Bond Index

3.92%


-0.01%


2.91%


Bloomberg U.S. Aggregate Bond Index

3.14%


-0.68%


1.80%




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

&#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.





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
      contextRef="C000088097_ClassMember_1YR"
      decimals="INF"
      id="ixv-497598"
      unitRef="pure">-0.0050</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088097_ClassMember_5YR"
      decimals="INF"
      id="ixv-497599"
      unitRef="pure">-0.0113</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088097_ClassMember_10YR"
      decimals="INF"
      id="ixv-497600"
      unitRef="pure">0.0239</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088097_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-497601"
      unitRef="pure">0.0364</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088097_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-497602"
      unitRef="pure">-0.0032</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088097_NoLoadClassMember_10YR"
      decimals="INF"
      id="ixv-497603"
      unitRef="pure">0.0281</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088097_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-497604"
      unitRef="pure">0.0392</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088097_0_AdditionalIndexMember_5YR"
      decimals="INF"
      id="ixv-497605"
      unitRef="pure">-0.0001</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088097_0_AdditionalIndexMember_10YR"
      decimals="INF"
      id="ixv-497606"
      unitRef="pure">0.0291</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088097_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-497607"
      unitRef="pure">0.0314</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088097_1_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-497608"
      unitRef="pure">-0.0068</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000088097_1_BBIndexMember_10YR"
      decimals="INF"
      id="ixv-497609"
      unitRef="pure">0.0180</oef:AvgAnnlRtrPct>
    <oef:UpdPerfInfoLocationTextBlock contextRef="C000088097_ClassMember" id="ixv-12133">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Visit &lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;institutional.fidelity.com&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt; for more recent performance information.&lt;/span&gt;</oef:UpdPerfInfoLocationTextBlock>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000088097_ClassMember" id="ixv-12145">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:italic;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-12149">&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-12155">&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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 2025)&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;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&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;text-align-last:auto;"&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;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&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;div style="text-align:left;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&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;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;2,081,012,659&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;600&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;7,046,841&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&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;text-align-last:auto;"&gt;&lt;/div&gt;
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&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;text-align-last:auto;"&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;text-align-last:auto;"&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;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
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&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
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&#160;
U.S. Government and U.S. Government Agency Obligations

9.2


AAA

0.1


AA

0.0


A

23.1


BBB

57.0


BB

4.9


B

1.3


Not Rated

0.1


Short-Term Investments and Net Other Assets (Liabilities)

4.3




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

U.S. Government and U.S. Government Agency Obligations - 9.2


&#160;

AAA - 0.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

AA - 0.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

A - 23.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BBB - 57.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

BB - 4.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

B - 1.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Not Rated - 0.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 4.3


&#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;
&#160;
&#160;
Corporate Bonds

85.3


U.S. Treasury Obligations

9.2


Asset-Backed Securities

0.6


Preferred Securities

0.3


Foreign Government and Government Agency Obligations

0.1


CMOs and Other Mortgage Related Securities

0.1


Other Investments

0.1


Municipal Securities

0.0


Short-Term Investments and Net Other Assets (Liabilities)

4.3




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

Corporate Bonds - 85.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

U.S. Treasury Obligations - 9.2&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Asset-Backed Securities - 0.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Preferred Securities - 0.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Foreign Government and Government Agency Obligations - 0.1


&#160;

CMOs and Other Mortgage Related Securities - 0.1


&#160;

Other Investments - 0.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Municipal Securities - 0.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Short-Term Investments and Net Other Assets (Liabilities) - 4.3


&#160;






United States

80.5


Canada

3.5


United Kingdom

3.3


Ireland

2.6


Germany

2.0


Japan

1.3


Switzerland

1.1


Netherlands

1.0


France

0.9


Others

3.8




GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

United States - 80.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Canada - 3.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

United Kingdom - 3.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Ireland - 2.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Germany - 2.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Japan - 1.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Switzerland - 1.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Netherlands - 1.0&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

France - 0.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Others - 3.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;




&#160;




&#160;
&#160;
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    <oef:LargestHoldingsTableTextBlock contextRef="C000088097_ClassMember" id="ixv-12691">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Bonds

9.2


&#160;


JPMorgan Chase &amp; Co

2.6


&#160;


Bank of America Corp

2.3


&#160;


Morgan Stanley

1.8


&#160;


Boeing Co

1.7


&#160;


Broadcom Inc

1.6


&#160;


Wells Fargo &amp; Co

1.5


&#160;


AerCap Ireland Capital DAC / AerCap Global Aviation Trust

1.3


&#160;


PNC Financial Services Group Inc/The

1.1


&#160;


Duke Energy Corp

1.1


&#160;


&#160;

24.2

&#160;



</oef:LargestHoldingsTableTextBlock>
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