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    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000014122_ClassMember" id="ixv-131">This semi-annual shareholder report contains information about Fidelity&#xae; Limited Term Government Fund for the period December 1, 2025 to May 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000014122_ClassMember" id="ixv-133">semi-annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000014122_ClassMember" id="ixv-138">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-153">&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;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 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;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;table cellpadding="0" cellspacing="0" style="border-collapse:collapse;border-style:none;" width="100%"&gt;&lt;tr&gt;&lt;td style="width:51%; 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:21%; 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;
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&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;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;
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&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;
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&lt;tr&gt;&lt;td style="width:51%; 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:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Limited Term Government 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;
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&lt;td style="width:27%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;0.30&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;
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&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;
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    <oef:AddlFundStatisticsTextBlock contextRef="C000014122_ClassMember" id="ixv-194">&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 May 31, 2026)&lt;/span&gt;&lt;/div&gt;
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&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;
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&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;226&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;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;113&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="C000014122_InstantMember"
      decimals="0"
      id="ixv-9607"
      unitRef="usd">159676648</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000014122_InstantMember"
      decimals="INF"
      id="ixv-9608"
      unitRef="holding">226</oef:HoldingsCount>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000014122_ClassMember"
      decimals="INF"
      id="ixv-9609"
      unitRef="pure">1.13</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000014122_ClassMember" id="ixv-254">
&#160;
COUPON DISTRIBUTION
(% of Fund's net assets)


1 - 1.99%

0.1

&#160;


2 - 2.99%

4.6

&#160;


3 - 3.99%

67.8

&#160;


4 - 4.99%

24.9

&#160;


5 - 5.99%

0.6

&#160;


6 - 6.99%

2.1

&#160;




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

78.5


CMOs and Other Mortgage Related Securities

15.3


U.S. Government Agency Obligations

3.2


U.S. Government Agency - Mortgage Securities

3.1


Options

0.4




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

U.S. Treasury Obligations - 78.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

CMOs and Other Mortgage Related Securities - 15.3


&#160;

U.S. Government Agency Obligations - 3.2


&#160;

U.S. Government Agency - Mortgage Securities - 3.1


&#160;

Options - 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;


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


&#160;






</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000014122_CD_0_Member"
      decimals="INF"
      id="ixv-9610"
      unitRef="pure">0.001</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000014122_CD_1_Member"
      decimals="INF"
      id="ixv-9611"
      unitRef="pure">0.046</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000014122_CD_2_Member"
      decimals="INF"
      id="ixv-9612"
      unitRef="pure">0.678</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000014122_CD_3_Member"
      decimals="INF"
      id="ixv-9613"
      unitRef="pure">0.249</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000014122_CD_4_Member"
      decimals="INF"
      id="ixv-9614"
      unitRef="pure">0.006</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000014122_CD_5_Member"
      decimals="INF"
      id="ixv-9615"
      unitRef="pure">0.021</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000014122_AA_USTreasuryObligations_Member"
      decimals="INF"
      id="ixv-9616"
      unitRef="pure">0.785</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000014122_AA_CMOsandOtherMortgageRelatedSecurities_Member"
      decimals="INF"
      id="ixv-9617"
      unitRef="pure">0.153</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000014122_AA_USGovernmentAgencyObligations_Member"
      decimals="INF"
      id="ixv-9618"
      unitRef="pure">0.032</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000014122_AA_USGovernmentAgencyMortgageSecurities_Member"
      decimals="INF"
      id="ixv-9619"
      unitRef="pure">0.031</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000014122_AA_Options_Member"
      decimals="INF"
      id="ixv-9620"
      unitRef="pure">0.004</oef:PctOfNav>
    <oef:LargestHoldingsTableTextBlock contextRef="C000014122_ClassMember" id="ixv-424">TOP HOLDINGS(% of Fund's net assets)

&#160;

&#160;


US Treasury Notes

77.5


&#160;


Freddie Mac Multifamily Structured pass-thru certificates

11.2


&#160;


Federal Farm Credit Banks Funding Corp

3.2


&#160;


Freddie Mac Gold Pool

2.5


&#160;


Fannie Mae Mortgage pass-thru certificates

1.7


&#160;


Ginnie Mae II Pool

1.1


&#160;


Fannie Mae Guaranteed REMIC

1.1


&#160;


US Treasury Bonds

1.0


&#160;


Ginnie Mae Mortgage pass-thru certificates

0.5


&#160;


Ginnie Mae REMIC pass-thru certificates

0.1


&#160;


&#160;

99.9

&#160;



</oef:LargestHoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000014122_TH_0_Member"
      decimals="INF"
      id="ixv-9621"
      unitRef="pure">0.775</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000014122_TH_1_Member"
      decimals="INF"
      id="ixv-9622"
      unitRef="pure">0.112</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000014122_TH_2_Member"
      decimals="INF"
      id="ixv-9623"
      unitRef="pure">0.032</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000014122_TH_3_Member"
      decimals="INF"
      id="ixv-9624"
      unitRef="pure">0.025</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000014122_TH_4_Member"
      decimals="INF"
      id="ixv-9625"
      unitRef="pure">0.017</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000014122_TH_5_Member"
      decimals="INF"
      id="ixv-9626"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000014122_TH_6_Member"
      decimals="INF"
      id="ixv-9627"
      unitRef="pure">0.011</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000014122_TH_7_Member"
      decimals="INF"
      id="ixv-9628"
      unitRef="pure">0.010</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000014122_TH_8_Member"
      decimals="INF"
      id="ixv-9629"
      unitRef="pure">0.005</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000014122_TH_9_Member"
      decimals="INF"
      id="ixv-9630"
      unitRef="pure">0.001</oef:PctOfNav>
</xbrl>
