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    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000014122_ClassMember" id="ixv-142">This semi-annual shareholder report contains information about Fidelity&#xae; Limited Term Government Fund for the period December 1, 2023 to May 31, 2024.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000014122_ClassMember" id="ixv-144">semi-annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000014122_ClassMember" id="ixv-149">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="C000014122_ClassMember" id="ixv-164">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;What were your Fund costs for the last six months?&lt;/span&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(based on hypothetical $10,000 investment)&lt;/span&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:41%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs of a $10,000 investment&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:31%; background-color:#dfe0e4;border:1px solid #dfe0e4;padding:0px 0px 0px 0px;" valign="bottom"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;"&gt;Costs paid as a percentage of a $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
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&lt;tr&gt;&lt;td style="width:41%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Limited Term Government Fund &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:27%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$ &lt;/span&gt;15&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:31%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;0.30&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:center;"&gt;&lt;/div&gt;
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&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:ExpensesTextBlock>
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    <oef:AddlFundStatisticsTextBlock contextRef="C000014122_ClassMember" id="ixv-206">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;span style="line-height:16px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of May 31, 2024)&lt;/span&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;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fund Size&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;233,596,758&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Number of Holdings&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;300&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:63%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:left;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;Portfolio Turnover&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:32%; border-bottom:1px dashed #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:right;"&gt;84&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;%&lt;/span&gt;&lt;/div&gt;
&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:right;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;div style="text-align:left;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
    <us-gaap:AssetsNet
      contextRef="C000014122_InstantMember"
      decimals="0"
      id="ixv-10555"
      unitRef="usd">233596758</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000014122_InstantMember"
      decimals="INF"
      id="ixv-10556"
      unitRef="holding">300</oef:HoldingsCount>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000014122_ClassMember"
      decimals="INF"
      id="ixv-10557"
      unitRef="pure">0.84</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000014122_ClassMember" id="ixv-269">
&#160;

COUPON DISTRIBUTION
(% of Fund's net assets)


0.01 - 0.99%

22.1
&#160;

&#160;


1 - 1.99%

7.7
&#160;

&#160;


2 - 2.99%

16.1
&#160;

&#160;


3 - 3.99%

17.1
&#160;

&#160;


4 - 4.99%

30.8
&#160;

&#160;


5 - 5.99%

2.0
&#160;

&#160;


6 - 6.99%

0.6
&#160;

&#160;


7 - 7.99%

0.0
&#160;

&#160;


8 - 8.99%

0.0
&#160;

&#160;




&#160;

U.S. Treasury Obligations

74.6


CMOs and Other Mortgage Related Securities

15.3


U.S. Government Agency - Mortgage Securities

6.1


Corporate Bonds

0.4


Short-Term Investments and Net Other Assets (Liabilities)

3.6




ASSET ALLOCATION (% of Fund's net assets)









</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000014122_CD_0_Member"
      decimals="INF"
      id="ixv-10558"
      unitRef="pure">0.221</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000014122_CD_1_Member"
      decimals="INF"
      id="ixv-10559"
      unitRef="pure">0.077</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000014122_CD_2_Member"
      decimals="INF"
      id="ixv-10560"
      unitRef="pure">0.161</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000014122_CD_3_Member"
      decimals="INF"
      id="ixv-10561"
      unitRef="pure">0.171</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000014122_CD_4_Member"
      decimals="INF"
      id="ixv-10562"
      unitRef="pure">0.308</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000014122_CD_5_Member"
      decimals="INF"
      id="ixv-10563"
      unitRef="pure">0.020</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000014122_CD_6_Member"
      decimals="INF"
      id="ixv-10564"
      unitRef="pure">0.006</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000014122_CD_7_Member"
      decimals="INF"
      id="ixv-10565"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000014122_CD_8_Member"
      decimals="INF"
      id="ixv-10566"
      unitRef="pure">0.000</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000014122_AA_USTreasuryObligations_Member"
      decimals="INF"
      id="ixv-10567"
      unitRef="pure">0.746</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000014122_AA_CMOsandOtherMortgageRelatedSecurities_Member"
      decimals="INF"
      id="ixv-10568"
      unitRef="pure">0.153</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000014122_AA_USGovernmentAgencyMortgageSecurities_Member"
      decimals="INF"
      id="ixv-10569"
      unitRef="pure">0.061</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000014122_AA_CorporateBonds_Member"
      decimals="INF"
      id="ixv-10570"
      unitRef="pure">0.004</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000014122_AA_ShortTermInvestmentsandNetOtherAssetsLiabilities_Member"
      decimals="INF"
      id="ixv-10571"
      unitRef="pure">0.036</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000014122_ClassMember" id="ixv-432">
TOP HOLDINGS
(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

73.4
&#160;

&#160;


Freddie Mac Multifamily Structured Pass Through Certificates

9.1
&#160;

&#160;


Fannie Mae Mortgage pass-thru certificates

3.8
&#160;

&#160;


Fannie Mae Guaranteed REMICS

3.6
&#160;

&#160;


Freddie Mac Gold Pool

2.5
&#160;

&#160;


US Treasury Bonds

1.2
&#160;

&#160;


Fremf 2015-Kplb Mortgage Trust

1.0
&#160;

&#160;


Ginnie Mae Mortgage pass-thru certificates

0.7
&#160;

&#160;


Private Export Funding Corp

0.4
&#160;

&#160;


Freddie Mac Multiclass Mortgage participation certificates

0.4
&#160;

&#160;


&#160;

96.1

&#160;


&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000014122_TH_0_Member"
      decimals="INF"
      id="ixv-10572"
      unitRef="pure">0.734</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000014122_TH_1_Member"
      decimals="INF"
      id="ixv-10573"
      unitRef="pure">0.091</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000014122_TH_2_Member"
      decimals="INF"
      id="ixv-10574"
      unitRef="pure">0.038</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000014122_TH_3_Member"
      decimals="INF"
      id="ixv-10575"
      unitRef="pure">0.036</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000014122_TH_4_Member"
      decimals="INF"
      id="ixv-10576"
      unitRef="pure">0.025</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000014122_TH_5_Member"
      decimals="INF"
      id="ixv-10577"
      unitRef="pure">0.012</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000014122_TH_6_Member"
      decimals="INF"
      id="ixv-10578"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000014122_TH_7_Member"
      decimals="INF"
      id="ixv-10579"
      unitRef="pure">0.007</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000014122_TH_8_Member"
      decimals="INF"
      id="ixv-10580"
      unitRef="pure">0.004</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000014122_TH_9_Member"
      decimals="INF"
      id="ixv-10581"
      unitRef="pure">0.004</oef:PctOfNav>
</xbrl>
