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    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000126039_ClassMember" id="ixv-136">This annual shareholder report contains information about Fidelity&#xae; Multi-Asset Index Fund for the period March 1, 2024 to February 28, 2025.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000126039_ClassMember" id="ixv-138">annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000126039_ClassMember" id="ixv-143">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>
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    <oef:ExpensesTextBlock contextRef="C000126039_ClassMember" id="ixv-158">&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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:45%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Multi-Asset Index Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:24%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;9&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;0.08&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;
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    <oef:FactorsAffectingPerfTextBlock contextRef="C000126039_ClassMember" id="ixv-200">&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;Risk assets largely achieved positive results for the 12 months ending February 28, 2025, influenced by an expanding global economy, a slowing in the pace of inflation in certain markets, and a pivot by some central banks toward monetary easing, despite ongoing geopolitical risk.&#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;Against this backdrop, U.S. equities gained 17.50% for the 12 months ending February 28, 2025, according to the Dow Jones U.S. Total Stock Market Index, driven by strong corporate profits, the potential for artificial intelligence and the Federal Reserve's pivot to cutting interest rates.&#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;By U.S. equity sector, utilities (+32%), financials (+31%) and communication services (+28%) led. Utilities was boosted by surging demand for electricity to power data centers used for AI, while the larger communication services and information technology (+18%) sectors continued to benefit from AI. Financials, meanwhile, rose following the election, driven by expectations for easing regulation. Conversely, materials and health care (+4% each) lagged most, as investors preferred higher-growth categories.&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;International equities gained 9.84% for the 12 months ending February 28, 2025, according to the MSCI ACWI (All Country World Index) ex USA Index. By region, the U.K. (+19%) led the way, followed by Canada (+16%). Asia Pacific ex Japan and emerging markets (+11% each), along with Europe ex U.K. (+10%), topped the broader index, whereas Japan (+1%) lagged.&#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 gained 5.81% for the period, per the Bloomberg U.S. Aggregate Bond Index. From a sub-sector perspective, investment-grade corporate bonds (+6.41%) topped short-term Treasurys (+5.21%) and long-term U.S. Treasury bonds (+3.43%). Commercial mortgage-backed securities gained 7.15% and agencies rose 5.44% the past 12 months. Outside the index, emerging-markets debt (+9.34%), U.S. high-yield bonds (+8.51%), floating-rate leveraged loans (+8.25%) and Treasury Inflation-Protected Securities (+6.36%) achieved strong gains.&lt;/span&gt;&lt;/div&gt;
&lt;div&gt;&lt;span style="font-size:13px;"&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;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:FactorsAffectingPerfTextBlock>
    <oef:LineGraphTableTextBlock contextRef="C000126039_ClassMember" id="ixv-224">How did the Fund perform over the past 10 years?

 &#160;&#160;
CUMULATIVE PERFORMANCE
February 28, 2015 through February 28, 2025.
Initial investment of $10,000.
Fidelity&#xae; Multi-Asset Index Fund


$10,000

$9,153


$10,954


$12,544


$12,824


$13,578


$17,257


$18,478


$16,920


$20,087


$22,662



Fidelity Multi-Asset Composite Index&#x2120;


$10,000

$9,168


$10,989


$12,609


$12,888


$13,624


$17,366


$18,621


$17,066


$20,280


$22,884



S&amp;P 500&#xae; Index


$10,000

$9,381


$11,724


$13,729


$14,371


$15,549


$20,414


$23,759


$21,932


$28,611


$33,877



&#160;

2015

2016

2017

2018

2019

2020

2021

2022

2023

2024

2025









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      id="ixv-5302"
      unitRef="usd">15549</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000126039_2_AdditionalIndexMember_AsOf_2021"
      decimals="0"
      id="ixv-5303"
      unitRef="usd">20414</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000126039_2_AdditionalIndexMember_AsOf_2022"
      decimals="0"
      id="ixv-5304"
      unitRef="usd">23759</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000126039_2_AdditionalIndexMember_AsOf_2023"
      decimals="0"
      id="ixv-5305"
      unitRef="usd">21932</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000126039_2_AdditionalIndexMember_AsOf_2024"
      decimals="0"
      id="ixv-5306"
      unitRef="usd">28611</oef:AcctVal>
    <oef:AcctVal
      contextRef="C000126039_2_AdditionalIndexMember_AsOf_2025"
      decimals="0"
      id="ixv-5307"
      unitRef="usd">33877</oef:AcctVal>
    <oef:AvgAnnlRtrTableTextBlock contextRef="C000126039_ClassMember" id="ixv-439">AVERAGE ANNUAL TOTAL RETURNS:

&#160;

1 Year

5 Year

10 Year


Fidelity&#xae; Multi-Asset Index Fund

12.82%

10.79%

8.53%


Fidelity Multi-Asset Composite Index&#x2120;

12.84%


10.93%


8.63%


S&amp;P 500&#xae; Index

18.41%


16.85%


12.98%




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


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





</oef:AvgAnnlRtrTableTextBlock>
    <oef:AvgAnnlRtrPct
      contextRef="C000126039_NoLoadClassMember_1YR"
      decimals="INF"
      id="ixv-5308"
      unitRef="pure">0.1282</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000126039_NoLoadClassMember_5YR"
      decimals="INF"
      id="ixv-5309"
      unitRef="pure">0.1079</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000126039_NoLoadClassMember_10YR"
      decimals="INF"
      id="ixv-5310"
      unitRef="pure">0.0853</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000126039_0_AdditionalIndexMember_1YR"
      decimals="INF"
      id="ixv-5311"
      unitRef="pure">0.1284</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000126039_0_AdditionalIndexMember_5YR"
      decimals="INF"
      id="ixv-5312"
      unitRef="pure">0.1093</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000126039_0_AdditionalIndexMember_10YR"
      decimals="INF"
      id="ixv-5313"
      unitRef="pure">0.0863</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000126039_1_BBIndexMember_1YR"
      decimals="INF"
      id="ixv-5314"
      unitRef="pure">0.1841</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000126039_1_BBIndexMember_5YR"
      decimals="INF"
      id="ixv-5315"
      unitRef="pure">0.1685</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="C000126039_1_BBIndexMember_10YR"
      decimals="INF"
      id="ixv-5316"
      unitRef="pure">0.1298</oef:AvgAnnlRtrPct>
    <oef:PerformancePastDoesNotIndicateFuture contextRef="C000126039_ClassMember" id="ixv-516">&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="C000126039_ClassMember" id="ixv-520">&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="C000126039_ClassMember" id="ixv-526">&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 February 28, 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;$&lt;/span&gt;8,470,903,148&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;7&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Total Advisory Fee&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;8,342,490&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;12&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="C000126039_InstantMember"
      decimals="0"
      id="ixv-5317"
      unitRef="usd">8470903148</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000126039_InstantMember"
      decimals="INF"
      id="ixv-5318"
      unitRef="holding">7</oef:HoldingsCount>
    <oef:AdvisoryFeesPaidAmt
      contextRef="C000126039_ClassMember"
      decimals="0"
      id="ixv-5319"
      unitRef="usd">8342490</oef:AdvisoryFeesPaidAmt>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000126039_ClassMember"
      decimals="INF"
      id="ixv-5320"
      unitRef="pure">0.12</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000126039_ClassMember" id="ixv-601">
&#160;
&#160;
&#160;
&#160;
Domestic Equity Funds

51.3


International Equity Funds

33.8


Bond Funds

14.9


Short-Term Investments and Net Other Assets (Liabilities)

0.0




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

Domestic Equity Funds - 51.3&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

International Equity Funds - 33.8&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Bond Funds - 14.9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

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


&#160;






</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000126039_AA_DomesticEquityFunds_Member"
      decimals="INF"
      id="ixv-5321"
      unitRef="pure">0.513</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000126039_AA_InternationalEquityFunds_Member"
      decimals="INF"
      id="ixv-5322"
      unitRef="pure">0.338</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000126039_AA_BondFunds_Member"
      decimals="INF"
      id="ixv-5323"
      unitRef="pure">0.149</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000126039_AA_ShortTermInvestmentsandNetOtherAssetsLiabilities_Member"
      decimals="INF"
      id="ixv-5324"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000126039_ClassMember" id="ixv-692">TOP HOLDINGS
(% of Fund's net assets)

&#160;

&#160;


Fidelity 500 Index Fund

41.3


&#160;


Fidelity International Index Fund

23.9


&#160;


Fidelity Extended Market Index Fund

10.0


&#160;


Fidelity Emerging Markets Index Fund

9.9


&#160;


Fidelity U.S. Bond Index Fund

6.9


&#160;


Fidelity Long-Term Treasury Bond Index Fund

5.0


&#160;


Fidelity International Bond Index Fund

3.0


&#160;


&#160;

100.0

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000126039_TH_0_Member"
      decimals="INF"
      id="ixv-5325"
      unitRef="pure">0.413</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000126039_TH_1_Member"
      decimals="INF"
      id="ixv-5326"
      unitRef="pure">0.239</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000126039_TH_2_Member"
      decimals="INF"
      id="ixv-5327"
      unitRef="pure">0.100</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000126039_TH_3_Member"
      decimals="INF"
      id="ixv-5328"
      unitRef="pure">0.099</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000126039_TH_4_Member"
      decimals="INF"
      id="ixv-5329"
      unitRef="pure">0.069</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000126039_TH_5_Member"
      decimals="INF"
      id="ixv-5330"
      unitRef="pure">0.050</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000126039_TH_6_Member"
      decimals="INF"
      id="ixv-5331"
      unitRef="pure">0.030</oef:PctOfNav>
</xbrl>
