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    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000238263_ClassMember" id="ixv-132">This semi-annual shareholder report contains information about Fidelity&#xae; California Municipal Money Market Fund for the period March 1, 2026 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000238263_ClassMember" id="ixv-134">semi-annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000238263_ClassMember" id="ixv-139">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="C000238263_ClassMember" id="ixv-154">&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 $10,000 investment &lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:1%; " valign="top"&gt;&lt;span style="line-height:12px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;&lt;td style="width:51%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="top"&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:12px;color:#000000;font-style:normal;font-weight:normal;"&gt;Fidelity&#xae; California Municipal Money Market Fund&lt;/span&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;&#160;&lt;/span&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:21%; border-bottom:1px solid #000000;padding:0px 0px 0px 0px;" valign="middle"&gt;&lt;div style="text-align:center;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;$&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>
    <oef:ExpensesPaidAmt
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    <oef:AddlFundStatisticsTextBlock contextRef="C000238263_ClassMember" id="ixv-195">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 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;6,917,673,857&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;436&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="C000238263_InstantMember"
      decimals="0"
      id="ixv-13984"
      unitRef="usd">6917673857</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000238263_InstantMember"
      decimals="INF"
      id="ixv-13985"
      unitRef="holding">436</oef:HoldingsCount>
    <oef:HoldingsTableTextBlock contextRef="C000238263_ClassMember" id="ixv-244">
&#160;
EFFECTIVE MATURITY DIVERSIFICATION
(% of Fund's net assets)


&#160;
Days
&#160;


1-7

43.1

&#160;


8-30

35.9

&#160;


31-60

9.4

&#160;


61-90

3.2

&#160;


91-180

4.9

&#160;


&gt;180

4.0

&#160;


&#160;
&#160;




&#160;
&#160;
&#160;
Tender Option Bond

36.6


Variable Rate Demand Notes (VRDNs)

23.9


Commercial Paper

18.1


Municipal Securities

8.1


Net Other Assets (Liabilities)

13.3




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

Tender Option Bond - 36.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Variable Rate Demand Notes (VRDNs) - 23.9


&#160;

Commercial Paper - 18.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Municipal Securities - 8.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Net Other Assets (Liabilities) - 13.3&#160;&#160;&#160;


&#160;






</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
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      decimals="INF"
      id="ixv-13986"
      unitRef="pure">0.431</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000238263_EMD_1_Member"
      decimals="INF"
      id="ixv-13987"
      unitRef="pure">0.359</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000238263_EMD_2_Member"
      decimals="INF"
      id="ixv-13988"
      unitRef="pure">0.094</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000238263_EMD_3_Member"
      decimals="INF"
      id="ixv-13989"
      unitRef="pure">0.032</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000238263_EMD_4_Member"
      decimals="INF"
      id="ixv-13990"
      unitRef="pure">0.049</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000238263_EMD_5_Member"
      decimals="INF"
      id="ixv-13991"
      unitRef="pure">0.040</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000238263_AA_TenderOptionBond_Member"
      decimals="INF"
      id="ixv-13992"
      unitRef="pure">0.366</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000238263_AA_VariableRateDemandNotesVRDNs_Member"
      decimals="INF"
      id="ixv-13993"
      unitRef="pure">0.239</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000238263_AA_CommercialPaper_Member"
      decimals="INF"
      id="ixv-13994"
      unitRef="pure">0.181</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000238263_AA_MunicipalSecurities_Member"
      decimals="INF"
      id="ixv-13995"
      unitRef="pure">0.081</oef:PctOfNav>
    <oef:PctOfNav
      contextRef="C000238263_AA_NetOtherAssetsLiabilities_Member"
      decimals="INF"
      id="ixv-13996"
      unitRef="pure">0.133</oef:PctOfNav>
    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-472">2026-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000014951_ClassMember" id="ixv-484">Fidelity&#xae; California Municipal Money Market Fund</oef:FundName>
    <oef:ClassName contextRef="C000014951_ClassMember" id="ixv-487">Fidelity&#xae; California Municipal Money Market Fund Premium Class</oef:ClassName>
    <dei:TradingSymbol contextRef="C000014951_ClassMember" id="ixv-491">FSPXX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000014951_ClassMember" id="ixv-510">This semi-annual shareholder report contains information about Fidelity&#xae; California Municipal Money Market Fund for the period March 1, 2026 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000014951_ClassMember" id="ixv-512">semi-annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000014951_ClassMember" id="ixv-517">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="C000014951_ClassMember" id="ixv-519">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000014951_ClassMember" id="ixv-522">1-800-544-8544</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000014951_ClassMember" id="ixv-525">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000014951_ClassMember" id="ixv-532">&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="C000014951_ClassMember"
      decimals="0"
      id="ixv-13997"
      unitRef="usd">15</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
      contextRef="C000014951_ClassMember"
      decimals="INF"
      id="ixv-13998"
      unitRef="pure">0.0030</oef:ExpenseRatioPct>
    <oef:AddlFundStatisticsTextBlock contextRef="C000014951_ClassMember" id="ixv-573">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 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;6,917,673,857&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;436&lt;/div&gt;
&lt;div style="text-align:right;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;td style="width:5%; " valign="top"&gt;&lt;span style="line-height:11px;"&gt;&#160;&lt;/span&gt;&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;</oef:AddlFundStatisticsTextBlock>
    <us-gaap:AssetsNet
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      decimals="0"
      id="ixv-13999"
      unitRef="usd">6917673857</us-gaap:AssetsNet>
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    <oef:HoldingsTableTextBlock contextRef="C000014951_ClassMember" id="ixv-622">
&#160;
EFFECTIVE MATURITY DIVERSIFICATION
(% of Fund's net assets)


&#160;
Days
&#160;


1-7

43.1

&#160;


8-30

35.9

&#160;


31-60

9.4

&#160;


61-90

3.2

&#160;


91-180

4.9

&#160;


&gt;180

4.0

&#160;


&#160;
&#160;




&#160;
&#160;
&#160;
Tender Option Bond

36.6


Variable Rate Demand Notes (VRDNs)

23.9


Commercial Paper

18.1


Municipal Securities

8.1


Net Other Assets (Liabilities)

13.3




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

Tender Option Bond - 36.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Variable Rate Demand Notes (VRDNs) - 23.9


&#160;

Commercial Paper - 18.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Municipal Securities - 8.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Net Other Assets (Liabilities) - 13.3&#160;&#160;&#160;


&#160;






</oef:HoldingsTableTextBlock>
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    <dei:DocumentPeriodEndDate contextRef="Trust" id="ixv-850">2026-08-31</dei:DocumentPeriodEndDate>
    <oef:FundName contextRef="C000047918_ClassMember" id="ixv-862">Fidelity&#xae; California Municipal Money Market Fund</oef:FundName>
    <oef:ClassName contextRef="C000047918_ClassMember" id="ixv-865">Fidelity&#xae; California Municipal Money Market Fund Institutional Class</oef:ClassName>
    <dei:TradingSymbol contextRef="C000047918_ClassMember" id="ixv-869">FSBXX</dei:TradingSymbol>
    <oef:AnnlOrSemiAnnlStatementTextBlock contextRef="C000047918_ClassMember" id="ixv-888">This semi-annual shareholder report contains information about Fidelity&#xae; California Municipal Money Market Fund for the period March 1, 2026 to August 31, 2026.</oef:AnnlOrSemiAnnlStatementTextBlock>
    <oef:ShareholderReportAnnualOrSemiAnnual contextRef="C000047918_ClassMember" id="ixv-890">semi-annual shareholder report</oef:ShareholderReportAnnualOrSemiAnnual>
    <oef:AddlInfoTextBlock contextRef="C000047918_ClassMember" id="ixv-895">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="C000047918_ClassMember" id="ixv-897">fundresearch.fidelity.com/prospectus/sec</oef:AddlInfoWebsite>
    <oef:AddlInfoPhoneNumber contextRef="C000047918_ClassMember" id="ixv-900">1-877-208-0098</oef:AddlInfoPhoneNumber>
    <oef:AddlInfoEmail contextRef="C000047918_ClassMember" id="ixv-903">fidfunddocuments@fidelity.com</oef:AddlInfoEmail>
    <oef:ExpensesTextBlock contextRef="C000047918_ClassMember" id="ixv-910">&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
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      decimals="0"
      id="ixv-14012"
      unitRef="usd">10</oef:ExpensesPaidAmt>
    <oef:ExpenseRatioPct
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      id="ixv-14013"
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    <oef:AddlFundStatisticsTextBlock contextRef="C000047918_ClassMember" id="ixv-951">&lt;span style="font-family:'Fidelity Sans';font-size:16px;color:#368627;font-style:normal;font-weight:bold;"&gt;Key Fund Statistics&lt;/span&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;/div&gt;
&lt;div style="text-align:left;text-align-last:auto;"&gt;&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;"&gt;(as of August 31, 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;6,917,673,857&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;436&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="C000047918_InstantMember"
      decimals="0"
      id="ixv-14014"
      unitRef="usd">6917673857</us-gaap:AssetsNet>
    <oef:HoldingsCount
      contextRef="C000047918_InstantMember"
      decimals="INF"
      id="ixv-14015"
      unitRef="holding">436</oef:HoldingsCount>
    <oef:HoldingsTableTextBlock contextRef="C000047918_ClassMember" id="ixv-1000">
&#160;
EFFECTIVE MATURITY DIVERSIFICATION
(% of Fund's net assets)


&#160;
Days
&#160;


1-7

43.1

&#160;


8-30

35.9

&#160;


31-60

9.4

&#160;


61-90

3.2

&#160;


91-180

4.9

&#160;


&gt;180

4.0

&#160;


&#160;
&#160;




&#160;
&#160;
&#160;
Tender Option Bond

36.6


Variable Rate Demand Notes (VRDNs)

23.9


Commercial Paper

18.1


Municipal Securities

8.1


Net Other Assets (Liabilities)

13.3




ASSET ALLOCATION (% of Fund's net assets)


&#160;



&#160;

Tender Option Bond - 36.6&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Variable Rate Demand Notes (VRDNs) - 23.9


&#160;

Commercial Paper - 18.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Municipal Securities - 8.1&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;


&#160;

Net Other Assets (Liabilities) - 13.3&#160;&#160;&#160;


&#160;






</oef:HoldingsTableTextBlock>
    <oef:PctOfNav
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      id="ixv-14016"
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    <oef:PctOfNav
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    <oef:PctOfNav
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      id="ixv-14018"
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      decimals="INF"
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      decimals="INF"
      id="ixv-14025"
      unitRef="pure">0.081</oef:PctOfNav>
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      id="ixv-14026"
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</xbrl>
