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    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000238262_ClassMember" id="ixv-136">This semi-annual shareholder report contains information about Fidelity&#xae; Massachusetts Municipal Money Market Fund for the period February 1, 2026 to July 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000238262_ClassMember" id="ixv-138">semi-annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000238262_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="C000238262_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 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;
&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;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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Massachusetts Municipal Money Market Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;21&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: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;0.42&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>
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    <oef:AddlFundStatisticsTextBlock contextRef="C000238262_ClassMember" id="ixv-199">&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 July 31, 2026)&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;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: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;
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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;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;3,982,131,065&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;259&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;
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&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
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&#160;
EFFECTIVE MATURITY DIVERSIFICATION
(% of Fund's net assets)


&#160;
Days
&#160;


1-7

74.7

&#160;


8-30

0.7

&#160;


31-60

5.2

&#160;


61-90

5.2

&#160;


91-180

4.0

&#160;


&gt;180

6.5

&#160;


&#160;
&#160;




&#160;
&#160;
&#160;
Variable Rate Demand Notes (VRDNs)

39.0


Municipal Securities

22.6


Tender Option Bond

21.5


Net Other Assets (Liabilities)

16.9




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

Variable Rate Demand Notes (VRDNs) - 39.0


&#160;

Municipal Securities - 22.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Tender Option Bond - 21.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Net Other Assets (Liabilities) - 16.9&#160;&#160;&#160;


&#160;






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    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-463">2026-07-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000019442_ClassMember" id="ixv-475">Fidelity&#xae; Massachusetts Municipal Money Market Fund</oef:FundName>
    <oef:ClassName contextRef="C000019442_ClassMember" id="ixv-478">Fidelity&#xae; Massachusetts Municipal Money Market Fund Premium Class</oef:ClassName>
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    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000019442_ClassMember" id="ixv-501">This semi-annual shareholder report contains information about Fidelity&#xae; Massachusetts Municipal Money Market Fund for the period February 1, 2026 to July 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000019442_ClassMember" id="ixv-503">semi-annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000019442_ClassMember" id="ixv-508">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="C000019442_ClassMember" id="ixv-510">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000019442_ClassMember" id="ixv-513">1-800-544-8544</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000019442_ClassMember" id="ixv-516">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000019442_ClassMember" id="ixv-523">&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;
&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;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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;Premium Class&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&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: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;
&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="C000019442_ClassMember"
      decimals="0"
      id="ixv-22288"
      unitRef="usd">15</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000019442_ClassMember"
      decimals="INF"
      id="ixv-22289"
      unitRef="pure">0.0030</oef:ExpenseRatioPct>
    <oef:AddlFundStatisticsTextBlock contextRef="C000019442_ClassMember" id="ixv-564">&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 July 31, 2026)&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;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: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;3,982,131,065&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;259&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="C000019442_InstantMember"
      decimals="0"
      id="ixv-22290"
      unitRef="usd">3982131065</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000019442_InstantMember"
      decimals="INF"
      id="ixv-22291"
      unitRef="holding">259</oef:HoldingsCount>
    <oef:HoldingsTableTextBlock contextRef="C000019442_ClassMember" id="ixv-613">
&#160;
EFFECTIVE MATURITY DIVERSIFICATION
(% of Fund's net assets)


&#160;
Days
&#160;


1-7

74.7

&#160;


8-30

0.7

&#160;


31-60

5.2

&#160;


61-90

5.2

&#160;


91-180

4.0

&#160;


&gt;180

6.5

&#160;


&#160;
&#160;




&#160;
&#160;
&#160;
Variable Rate Demand Notes (VRDNs)

39.0


Municipal Securities

22.6


Tender Option Bond

21.5


Net Other Assets (Liabilities)

16.9




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

Variable Rate Demand Notes (VRDNs) - 39.0


&#160;

Municipal Securities - 22.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Tender Option Bond - 21.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Net Other Assets (Liabilities) - 16.9&#160;&#160;&#160;


&#160;






</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000019442_EMD_0_Member"
      decimals="INF"
      id="ixv-22292"
      unitRef="pure">0.747</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019442_EMD_1_Member"
      decimals="INF"
      id="ixv-22293"
      unitRef="pure">0.007</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019442_EMD_2_Member"
      decimals="INF"
      id="ixv-22294"
      unitRef="pure">0.052</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019442_EMD_3_Member"
      decimals="INF"
      id="ixv-22295"
      unitRef="pure">0.052</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019442_EMD_4_Member"
      decimals="INF"
      id="ixv-22296"
      unitRef="pure">0.040</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019442_EMD_5_Member"
      decimals="INF"
      id="ixv-22297"
      unitRef="pure">0.065</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019442_AA_VariableRateDemandNotesVRDNs_Member"
      decimals="INF"
      id="ixv-22298"
      unitRef="pure">0.390</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019442_AA_MunicipalSecurities_Member"
      decimals="INF"
      id="ixv-22299"
      unitRef="pure">0.226</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019442_AA_TenderOptionBond_Member"
      decimals="INF"
      id="ixv-22300"
      unitRef="pure">0.215</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019442_AA_NetOtherAssetsLiabilities_Member"
      decimals="INF"
      id="ixv-22301"
      unitRef="pure">0.169</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-828">2026-07-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000047913_ClassMember" id="ixv-840">Fidelity&#xae; Massachusetts Municipal Money Market Fund</oef:FundName>
    <oef:ClassName contextRef="C000047913_ClassMember" id="ixv-843">Fidelity&#xae; Massachusetts Municipal Money Market Fund Institutional Class</oef:ClassName>
    <dei:TradingSymbol contextRef="C000047913_ClassMember" id="ixv-847">FMAXX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000047913_ClassMember" id="ixv-866">This semi-annual shareholder report contains information about Fidelity&#xae; Massachusetts Municipal Money Market Fund for the period February 1, 2026 to July 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000047913_ClassMember" id="ixv-868">semi-annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000047913_ClassMember" id="ixv-873">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="C000047913_ClassMember" id="ixv-875">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000047913_ClassMember" id="ixv-878">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000047913_ClassMember" id="ixv-881">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000047913_ClassMember" id="ixv-888">&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;
&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;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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;Institutional Class&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;10&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: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;0.20&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="C000047913_ClassMember"
      decimals="0"
      id="ixv-22302"
      unitRef="usd">10</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000047913_ClassMember"
      decimals="INF"
      id="ixv-22303"
      unitRef="pure">0.0020</oef:ExpenseRatioPct>
    <oef:AddlFundStatisticsTextBlock contextRef="C000047913_ClassMember" id="ixv-929">&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 July 31, 2026)&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;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: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;3,982,131,065&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;259&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="C000047913_InstantMember"
      decimals="0"
      id="ixv-22304"
      unitRef="usd">3982131065</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000047913_InstantMember"
      decimals="INF"
      id="ixv-22305"
      unitRef="holding">259</oef:HoldingsCount>
    <oef:HoldingsTableTextBlock contextRef="C000047913_ClassMember" id="ixv-978">
&#160;
EFFECTIVE MATURITY DIVERSIFICATION
(% of Fund's net assets)


&#160;
Days
&#160;


1-7

74.7

&#160;


8-30

0.7

&#160;


31-60

5.2

&#160;


61-90

5.2

&#160;


91-180

4.0

&#160;


&gt;180

6.5

&#160;


&#160;
&#160;




&#160;
&#160;
&#160;
Variable Rate Demand Notes (VRDNs)

39.0


Municipal Securities

22.6


Tender Option Bond

21.5


Net Other Assets (Liabilities)

16.9




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

Variable Rate Demand Notes (VRDNs) - 39.0


&#160;

Municipal Securities - 22.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Tender Option Bond - 21.5&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Net Other Assets (Liabilities) - 16.9&#160;&#160;&#160;


&#160;






</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
      contextRef="C000047913_EMD_0_Member"
      decimals="INF"
      id="ixv-22306"
      unitRef="pure">0.747</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000047913_EMD_1_Member"
      decimals="INF"
      id="ixv-22307"
      unitRef="pure">0.007</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000047913_EMD_2_Member"
      decimals="INF"
      id="ixv-22308"
      unitRef="pure">0.052</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000047913_EMD_3_Member"
      decimals="INF"
      id="ixv-22309"
      unitRef="pure">0.052</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000047913_EMD_4_Member"
      decimals="INF"
      id="ixv-22310"
      unitRef="pure">0.040</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000047913_EMD_5_Member"
      decimals="INF"
      id="ixv-22311"
      unitRef="pure">0.065</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000047913_AA_VariableRateDemandNotesVRDNs_Member"
      decimals="INF"
      id="ixv-22312"
      unitRef="pure">0.390</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000047913_AA_MunicipalSecurities_Member"
      decimals="INF"
      id="ixv-22313"
      unitRef="pure">0.226</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000047913_AA_TenderOptionBond_Member"
      decimals="INF"
      id="ixv-22314"
      unitRef="pure">0.215</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000047913_AA_NetOtherAssetsLiabilities_Member"
      decimals="INF"
      id="ixv-22315"
      unitRef="pure">0.169</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-1193">2026-07-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000019443_ClassMember" id="ixv-1205">Fidelity&#xae; Massachusetts Municipal Income Fund</oef:FundName>
    <oef:ClassName contextRef="C000019443_ClassMember" id="ixv-1208">Fidelity&#xae; Massachusetts Municipal Income Fund</oef:ClassName>
    <dei:TradingSymbol contextRef="C000019443_ClassMember" id="ixv-1212">FDMMX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000019443_ClassMember" id="ixv-1231">This semi-annual shareholder report contains information about Fidelity&#xae; Massachusetts Municipal Income Fund for the period February 1, 2026 to July 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000019443_ClassMember" id="ixv-1233">semi-annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000019443_ClassMember" id="ixv-1238">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="C000019443_ClassMember" id="ixv-1240">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000019443_ClassMember" id="ixv-1243">1-800-544-8544</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000019443_ClassMember" id="ixv-1246">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000019443_ClassMember" id="ixv-1253">&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;
&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;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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; Massachusetts Municipal Income Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;22&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: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;0.45&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="C000019443_ClassMember"
      decimals="0"
      id="ixv-22316"
      unitRef="usd">22</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000019443_ClassMember"
      decimals="INF"
      id="ixv-22317"
      unitRef="pure">0.0045</oef:ExpenseRatioPct>
    <oef:AddlFundStatisticsTextBlock contextRef="C000019443_ClassMember" id="ixv-1294">&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 July 31, 2026)&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;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: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;1,622,881,034&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;467&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;24&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;/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="C000019443_InstantMember"
      decimals="0"
      id="ixv-22318"
      unitRef="usd">1622881034</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000019443_InstantMember"
      decimals="INF"
      id="ixv-22319"
      unitRef="holding">467</oef:HoldingsCount>
    <us-gaap:InvestmentCompanyPortfolioTurnover
      contextRef="C000019443_ClassMember"
      decimals="INF"
      id="ixv-22320"
      unitRef="pure">0.24</us-gaap:InvestmentCompanyPortfolioTurnover>
    <oef:HoldingsTableTextBlock contextRef="C000019443_ClassMember" id="ixv-1354">
&#160;
REVENUE SOURCES
 (% of Fund's net assets)


General Obligations

32.0

&#160;


Education

17.7

&#160;


Transportation

12.7

&#160;


Special Tax

11.0

&#160;


Health Care

10.4

&#160;


Water &amp; Sewer

5.8

&#160;


Others(Individually Less Than 5%)

7.2

&#160;


96.8

&#160;


&#160;




&#160;
AAA

9.5


AA

62.6


A

8.3


BBB

12.6


BB

1.8


Not Rated

2.0


Short-Term Investments and Net Other Assets (Liabilities)

3.2




QUALITY DIVERSIFICATION (% of Fund's net assets)


&#160;



&#160;

AAA - 9.5&#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 - 62.6&#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;

A - 8.3&#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;

BBB - 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;

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;

Not Rated - 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;

Short-Term Investments and Net Other Assets (Liabilities) - 3.2


&#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;
</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-22321"
      unitRef="pure">0.320</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019443_RS_1_Member"
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      id="ixv-22322"
      unitRef="pure">0.177</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019443_RS_2_Member"
      decimals="INF"
      id="ixv-22323"
      unitRef="pure">0.127</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019443_RS_3_Member"
      decimals="INF"
      id="ixv-22324"
      unitRef="pure">0.110</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019443_RS_4_Member"
      decimals="INF"
      id="ixv-22325"
      unitRef="pure">0.104</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019443_RS_5_Member"
      decimals="INF"
      id="ixv-22326"
      unitRef="pure">0.058</oef:PctOfNav>
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      decimals="INF"
      id="ixv-22327"
      unitRef="pure">0.072</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019443_QD_AAA_Member"
      decimals="INF"
      id="ixv-22328"
      unitRef="pure">0.095</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019443_QD_AA_Member"
      decimals="INF"
      id="ixv-22329"
      unitRef="pure">0.626</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019443_QD_A_Member"
      decimals="INF"
      id="ixv-22330"
      unitRef="pure">0.083</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019443_QD_BBB_Member"
      decimals="INF"
      id="ixv-22331"
      unitRef="pure">0.126</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019443_QD_BB_Member"
      decimals="INF"
      id="ixv-22332"
      unitRef="pure">0.018</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019443_QD_NotRated_Member"
      decimals="INF"
      id="ixv-22333"
      unitRef="pure">0.020</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000019443_QD_ShortTermInvestmentsandNetOtherAssetsLiabilities_Member"
      decimals="INF"
      id="ixv-22334"
      unitRef="pure">0.032</oef:PctOfNav>
</xbrl>
