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Fees and Expenses of the Fund</oef:ExpenseHeading>
    <oef:ExpenseNarrativeTextBlock
      contextRef="Context_20260630_20260630_S000006859Member_S000006859Summary1Member"
      id="ixv-501">&lt;p style="margin-top:revert; margin-bottom:revert; font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; text-decoration:none;"&gt;These tables describe the fees and expenses 
that you may pay if you buy, hold and sell shares of the Fund. Please note that the tables and examples 
below do not reflect any transaction fees that may be charged by financial intermediaries, or commissions 
that a shareholder may be required to pay directly to its financial intermediary when buying or selling 
Class R6 or Class A shares. Information about sales charge discounts and waivers for purchases of shares 
through specific financial intermediaries is set forth in Appendix A &#x2013; &#x201c;Intermediary Sales Charge 
Discounts and Waivers&#x201d; to the Fund&#x2019;s prospectus.&lt;/p&gt;</oef:ExpenseNarrativeTextBlock>
    <oef:ShareholderFeesCaption
      contextRef="Context_20260630_20260630_S000006859Member_S000006859Summary1Member"
      id="ixv-11852">Shareholder Fees</oef:ShareholderFeesCaption>
    <oef:MaximumSalesChargeImposedOnPurchasesOverOfferingPrice
      contextRef="Context_20260630_20260630_C000018536Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11853"
      unitRef="pure">0</oef:MaximumSalesChargeImposedOnPurchasesOverOfferingPrice>
    <oef:MaximumSalesChargeImposedOnPurchasesOverOfferingPrice
      contextRef="Context_20260630_20260630_C000213872Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11854"
      unitRef="pure">0</oef:MaximumSalesChargeImposedOnPurchasesOverOfferingPrice>
    <oef:MaximumSalesChargeImposedOnPurchasesOverOfferingPrice
      contextRef="Context_20260630_20260630_C000213873Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11855"
      unitRef="pure">0</oef:MaximumSalesChargeImposedOnPurchasesOverOfferingPrice>
    <oef:MaximumSalesChargeImposedOnPurchasesOverOfferingPrice
      contextRef="Context_20260630_20260630_C000128781Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11856"
      unitRef="pure">0</oef:MaximumSalesChargeImposedOnPurchasesOverOfferingPrice>
    <oef:MaximumDeferredSalesChargeOverOfferingPrice
      contextRef="Context_20260630_20260630_C000018536Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11857"
      unitRef="pure">0</oef:MaximumDeferredSalesChargeOverOfferingPrice>
    <oef:MaximumDeferredSalesChargeOverOfferingPrice
      contextRef="Context_20260630_20260630_C000213872Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11858"
      unitRef="pure">0.0100</oef:MaximumDeferredSalesChargeOverOfferingPrice>
    <oef:MaximumDeferredSalesChargeOverOfferingPrice
      contextRef="Context_20260630_20260630_C000213873Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11859"
      unitRef="pure">0</oef:MaximumDeferredSalesChargeOverOfferingPrice>
    <oef:MaximumDeferredSalesChargeOverOfferingPrice
      contextRef="Context_20260630_20260630_C000128781Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11860"
      unitRef="pure">0</oef:MaximumDeferredSalesChargeOverOfferingPrice>
    <oef:OperatingExpensesCaption
      contextRef="Context_20260630_20260630_S000006859Member_S000006859Summary1Member"
      id="ixv-11861">Annual Fund Operating Expenses (expenses 
that you pay each year as a percentage of the value of your investment)</oef:OperatingExpensesCaption>
    <oef:ManagementFeesOverAssets
      contextRef="Context_20260630_20260630_C000018536Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11862"
      unitRef="pure">0.0015</oef:ManagementFeesOverAssets>
    <oef:ManagementFeesOverAssets
      contextRef="Context_20260630_20260630_C000213872Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11863"
      unitRef="pure">0.0015</oef:ManagementFeesOverAssets>
    <oef:ManagementFeesOverAssets
      contextRef="Context_20260630_20260630_C000213873Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11864"
      unitRef="pure">0.0015</oef:ManagementFeesOverAssets>
    <oef:ManagementFeesOverAssets
      contextRef="Context_20260630_20260630_C000128781Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11865"
      unitRef="pure">0.0015</oef:ManagementFeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Context_20260630_20260630_C000018536Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11866"
      unitRef="pure">0</oef:DistributionAndService12b1FeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Context_20260630_20260630_C000213872Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11867"
      unitRef="pure">0.0065</oef:DistributionAndService12b1FeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Context_20260630_20260630_C000213873Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11868"
      unitRef="pure">0.0050</oef:DistributionAndService12b1FeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Context_20260630_20260630_C000128781Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11869"
      unitRef="pure">0</oef:DistributionAndService12b1FeesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Context_20260630_20260630_C000018536Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11870"
      unitRef="pure">0.0035</oef:OtherExpensesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Context_20260630_20260630_C000213872Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11871"
      unitRef="pure">0.0035</oef:OtherExpensesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Context_20260630_20260630_C000213873Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11872"
      unitRef="pure">0.0036</oef:OtherExpensesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Context_20260630_20260630_C000128781Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11873"
      unitRef="pure">0.0034</oef:OtherExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Context_20260630_20260630_C000018536Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="_39_"
      unitRef="pure">0.0050</oef:ExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Context_20260630_20260630_C000213872Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="_40_"
      unitRef="pure">0.0115</oef:ExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Context_20260630_20260630_C000213873Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="_41_"
      unitRef="pure">0.0101</oef:ExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Context_20260630_20260630_C000128781Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="_42_"
      unitRef="pure">0.0049</oef:ExpensesOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssets
      contextRef="Context_20260630_20260630_C000018536Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="_43_"
      unitRef="pure">0</oef:FeeWaiverOrReimbursementOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssets
      contextRef="Context_20260630_20260630_C000213872Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="_44_"
      unitRef="pure">0</oef:FeeWaiverOrReimbursementOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssets
      contextRef="Context_20260630_20260630_C000213873Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="_45_"
      unitRef="pure">0</oef:FeeWaiverOrReimbursementOverAssets>
    <oef:FeeWaiverOrReimbursementOverAssets
      contextRef="Context_20260630_20260630_C000128781Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="_46_"
      unitRef="pure">-0.0002</oef:FeeWaiverOrReimbursementOverAssets>
    <oef:NetExpensesOverAssets
      contextRef="Context_20260630_20260630_C000018536Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="_47_"
      unitRef="pure">0.0050</oef:NetExpensesOverAssets>
    <oef:NetExpensesOverAssets
      contextRef="Context_20260630_20260630_C000213872Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="_48_"
      unitRef="pure">0.0115</oef:NetExpensesOverAssets>
    <oef:NetExpensesOverAssets
      contextRef="Context_20260630_20260630_C000213873Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="_49_"
      unitRef="pure">0.0101</oef:NetExpensesOverAssets>
    <oef:NetExpensesOverAssets
      contextRef="Context_20260630_20260630_C000128781Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="_50_"
      unitRef="pure">0.0047</oef:NetExpensesOverAssets>
    <oef:ExpenseExampleHeading
      contextRef="Context_20260630_20260630_S000006859Member_S000006859Summary1Member"
      id="ixv-11886">Example</oef:ExpenseExampleHeading>
    <oef:ExpenseExampleNarrativeTextBlock
      contextRef="Context_20260630_20260630_S000006859Member_S000006859Summary1Member"
      id="ixv-752">&lt;p style="margin-top:revert; margin-bottom:revert; font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; text-decoration:none;"&gt;This Example is intended 
to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. 
The Example assumes that you &lt;/p&gt;&lt;p style="margin-top:revert; margin-bottom:revert; font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; text-decoration:none;"&gt;invest 
$10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of the 
period. The Example also assumes that your investment has a 5% return each year and that the Fund's operating 
expenses remain the same. The Example reflects adjustments made to the Fund's operating expenses due 
to the fee waivers and/or expense reimbursements by management for the 1 Year numbers only. Although 
your actual costs may be higher or lower, based on these assumptions your costs would be:&lt;/p&gt;</oef:ExpenseExampleNarrativeTextBlock>
    <oef:ExpenseExampleYear01
      contextRef="Context_20260630_20260630_C000018536Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11887"
      unitRef="usd">51</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleYear03
      contextRef="Context_20260630_20260630_C000018536Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11888"
      unitRef="usd">160</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleYear05
      contextRef="Context_20260630_20260630_C000018536Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11889"
      unitRef="usd">279</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleYear10
      contextRef="Context_20260630_20260630_C000018536Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11890"
      unitRef="usd">629</oef:ExpenseExampleYear10>
    <oef:ExpenseExampleYear01
      contextRef="Context_20260630_20260630_C000213872Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11891"
      unitRef="usd">217</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleYear03
      contextRef="Context_20260630_20260630_C000213872Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11892"
      unitRef="usd">365</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleYear05
      contextRef="Context_20260630_20260630_C000213872Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11893"
      unitRef="usd">632</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleYear10
      contextRef="Context_20260630_20260630_C000213872Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11894"
      unitRef="usd">1215</oef:ExpenseExampleYear10>
    <oef:ExpenseExampleYear01
      contextRef="Context_20260630_20260630_C000213873Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11895"
      unitRef="usd">103</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleYear03
      contextRef="Context_20260630_20260630_C000213873Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11896"
      unitRef="usd">321</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleYear05
      contextRef="Context_20260630_20260630_C000213873Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11897"
      unitRef="usd">557</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleYear10
      contextRef="Context_20260630_20260630_C000213873Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11898"
      unitRef="usd">1234</oef:ExpenseExampleYear10>
    <oef:ExpenseExampleYear01
      contextRef="Context_20260630_20260630_C000128781Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11899"
      unitRef="usd">48</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleYear03
      contextRef="Context_20260630_20260630_C000128781Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11900"
      unitRef="usd">155</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleYear05
      contextRef="Context_20260630_20260630_C000128781Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11901"
      unitRef="usd">272</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleYear10
      contextRef="Context_20260630_20260630_C000128781Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11902"
      unitRef="usd">613</oef:ExpenseExampleYear10>
    <oef:ExpenseExampleNoRedemptionByYearCaption
      contextRef="Context_20260630_20260630_S000006859Member_S000006859Summary1Member"
      id="ixv-11903">If 
you do not sell your shares:</oef:ExpenseExampleNoRedemptionByYearCaption>
    <oef:ExpenseExampleNoRedemptionYear01
      contextRef="Context_20260630_20260630_C000213872Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11904"
      unitRef="usd">117</oef:ExpenseExampleNoRedemptionYear01>
    <oef:ExpenseExampleNoRedemptionYear03
      contextRef="Context_20260630_20260630_C000213872Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11905"
      unitRef="usd">365</oef:ExpenseExampleNoRedemptionYear03>
    <oef:ExpenseExampleNoRedemptionYear05
      contextRef="Context_20260630_20260630_C000213872Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11906"
      unitRef="usd">632</oef:ExpenseExampleNoRedemptionYear05>
    <oef:ExpenseExampleNoRedemptionYear10
      contextRef="Context_20260630_20260630_C000213872Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11907"
      unitRef="usd">1215</oef:ExpenseExampleNoRedemptionYear10>
    <oef:StrategyHeading
      contextRef="Context_20260630_20260630_S000006859Member_S000006859Summary1Member"
      id="ixv-11908">  
Principal Investment Strategies</oef:StrategyHeading>
    <oef:StrategyNarrativeTextBlock
      contextRef="Context_20260630_20260630_S000006859Member_S000006859Summary1Member"
      id="ixv-944">&lt;p style="margin-top:revert; margin-bottom:revert; font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; text-decoration:none;"&gt;The Fund is a &#x201c;feeder fund&#x201d; that invests, 
through the Master Portfolio, at least 99.5% of its total assets in Government securities, cash and repurchase 
agreements collateralized fully by Government securities or cash. In addition, under normal circumstances, 
the Fund invests, through the Master Portfolio, at least 80% of its net assets in Government securities 
and repurchase agreements collateralized fully by Government securities. In contrast to the Fund's 99.5% 
policy, the Fund's 80% policy does not include cash. For purposes of these policies, &#x201c;Government securities&#x201d; 
means any securities issued or guaranteed as to principal or interest by the United States, or by a person 
controlled or supervised by and acting as an instrumentality of the Government of the United States pursuant 
to authority granted by the Congress of the United States; or any certificate of deposit for any of the 
foregoing. Government securities include those issued by government agencies or instrumentalities, such 
as the Federal National Mortgage Association (Fannie Mae), Federal Home Loan Mortgage Corporation (Freddie 
Mac), Federal Home Loan Banks and Federal Farm Credit Banks, whose securities are neither issued nor 
guaranteed by the U.S. Government. The Fund intends to be a &#x201c;Government money market fund,&#x201d; as such 
term is defined in or interpreted under Rule 2a-7 under the Investment Company Act of 1940. Shareholders 
will be given at least 60 days&#x2019; advance notice of any change to the 99.5% and 80% policies.&lt;/p&gt;&lt;p style="margin-top:revert; margin-bottom:revert; font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; text-decoration:none;"&gt;The Fund uses the amortized 
cost method of valuation to seek to maintain a stable $1.00 share price.&lt;/p&gt;&lt;p style="margin-top:revert; margin-bottom:revert; font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; text-decoration:none;"&gt;Unless 
the context otherwise requires, references to the Fund&#x2019;s investments refer to those investments of 
the Master Portfolio to which the Fund is exposed and references to the investment manager or the Fund&#x2019;s 
investment manager refer to the Master Portfolio&#x2019;s investment manager.&lt;/p&gt;&lt;p style="margin-top:revert; margin-bottom:revert; font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; text-decoration:none;"&gt;The Fund invests in:&lt;/p&gt;&lt;p style="margin-top:revert; margin-bottom:revert; font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; font-style:normal;"&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:bold; text-decoration:none;"&gt;U.S. 
government securities&lt;/span&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:normal; text-decoration:none;"&gt; which may include fixed, floating and variable rate securities.&lt;/span&gt;&lt;/p&gt;&lt;p style="margin-top:revert; margin-bottom:revert; font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; font-style:normal;"&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:bold; text-decoration:none;"&gt;Repurchase 
agreements&lt;/span&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:normal; text-decoration:none;"&gt; which are agreements by the Fund to buy Government securities from a broker-dealer 
or other counterparty and then to sell the securities back to such counterparty on an agreed upon date 
(generally, less than seven days) at a higher price, which reflects prevailing short-term interest rates.&lt;/span&gt;&lt;/p&gt;&lt;p style="margin-top:revert; margin-bottom:revert; font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; font-style:normal;"&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:bold; text-decoration:none;"&gt;Portfolio 
maturity and quality&lt;/span&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:normal; text-decoration:none;"&gt; The Fund only buys securities that the investment manager determines present 
minimal credit risks. The Fund maintains a dollar-weighted average portfolio maturity of 60 calendar 
days or less, maintains a dollar-weighted average life for its portfolio of 120 calendar days or less, 
and only buys securities that mature or are deemed to mature in 397 calendar days or less.&lt;/span&gt;&lt;/p&gt;</oef:StrategyNarrativeTextBlock>
    <fnd:NmRule35d1EightyPctInvstmntPlcyTextBlock
      contextRef="Context_20260630_20260630_S000006859Member_S000006859Summary1Member"
      id="ixv-11910">In addition, under normal circumstances, 
the Fund invests, through the Master Portfolio, at least 80% of its net assets in Government securities 
and repurchase agreements collateralized fully by Government securities</fnd:NmRule35d1EightyPctInvstmntPlcyTextBlock>
    <fnd:NmRule35d1TermDfnSmryTextBlock
      contextRef="Context_20260630_20260630_S000006859Member_S000006859Summary1Member"
      id="ixv-11911"> In contrast to the Fund's 99.5% 
policy, the Fund's 80% policy does not include cash. For purposes of these policies, &#x201c;Government securities&#x201d; 
means any securities issued or guaranteed as to principal or interest by the United States, or by a person 
controlled or supervised by and acting as an instrumentality of the Government of the United States pursuant 
to authority granted by the Congress of the United States; or any certificate of deposit for any of the 
foregoing. Government securities include those issued by government agencies or instrumentalities, such 
as the Federal National Mortgage Association (Fannie Mae), Federal Home Loan Mortgage Corporation (Freddie 
Mac), Federal Home Loan Banks and Federal Farm Credit Banks, whose securities are neither issued nor 
guaranteed by the U.S. Government. The Fund intends to be a &#x201c;Government money market fund,&#x201d; as such 
term is defined in or interpreted under Rule 2a-7 under the Investment Company Act of 1940. Shareholders 
will be given at least 60 days&#x2019; advance notice of any change to the 99.5% and 80% policies.</fnd:NmRule35d1TermDfnSmryTextBlock>
    <oef:RiskTextBlock
      contextRef="Context_20260630_20260630_S000006859Member_PrincipalRisks2_S000006859Summary1Member"
      id="ixv-977">&lt;p style="margin-top:revert; margin-bottom:revert; font-size:13.0pt; font-family:Arial; text-align:left; color:#004C97; font-weight:normal; font-style:normal;"&gt;&lt;span style="font-size:4.0pt; font-family:Arial; font-style:normal; color:#004C97; font-weight:normal; text-decoration:none;"&gt; 
&lt;/span&gt;&lt;a href="" id="x4x2"&gt;&lt;/a&gt;&lt;span style="font-size:13.0pt; font-family:Arial; font-style:normal; color:#004C97; font-weight:normal; text-decoration:none;"&gt; &lt;/span&gt;&lt;span style="font-size:13.0pt; font-family:Arial; font-style:normal; color:#004C97; font-weight:normal; text-decoration:none;"&gt;Principal Risks&lt;/span&gt;&lt;/p&gt;&lt;p style="margin-top:revert; margin-bottom:revert; font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; text-decoration:none;"&gt;You 
could lose money by investing in the Fund. Although the Fund seeks to preserve the value of your investment 
at $1.00 per share, it cannot guarantee it will do so. An investment in the Fund is not a bank account 
and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government 
agency. The Fund&#x2019;s sponsor is not required to reimburse the Fund for losses, and you should not expect 
that the sponsor will provide financial support to the Fund at any time, including during periods of 
market stress.&lt;/p&gt;</oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Context_20260630_20260630_S000006859Member_RiskLoseMoneyMember_S000006859Summary1Member"
      id="ixv-11912">You 
could lose money by investing in the Fund.</oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Context_20260630_20260630_S000006859Member_RiskMoneyMarketFundMayNotPreserveDollarMember_S000006859Summary1Member"
      id="ixv-11913">Although the Fund seeks to preserve the value of your investment 
at $1.00 per share, it cannot guarantee it will do so.</oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Context_20260630_20260630_S000006859Member_RiskNotInsuredMember_S000006859Summary1Member"
      id="ixv-11914">An investment in the Fund is not a bank account 
and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government 
agency.</oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Context_20260630_20260630_S000006859Member_InterestRate2_S000006859Summary1Member"
      id="ixv-984">&lt;p style="margin-top:revert; margin-bottom:revert; font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; font-style:normal;"&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; color:#004C97; font-weight:bold; text-decoration:none;"&gt;Interest Rate:&lt;/span&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:normal; text-decoration:none;"&gt;  When interest rates rise, debt security 
prices generally fall. The opposite is also generally true: debt security prices rise when interest rates 
fall. Interest rate changes are influenced by a number of factors, including government policy, monetary 
policy, inflation expectations, perceptions of risk, and supply of and demand for debt securities. The 
Fund's yield will vary. A low interest or negative rate environment may prevent the Fund from providing 
a positive yield or paying Fund expenses out of current income and could impair the Fund's ability to 
maintain a stable net asset value. A sharp and unexpected rise in interest rates could cause the Fund's 
share price to drop below a dollar. In general, securities with longer maturities or durations are more 
sensitive to these interest rate changes. &lt;/span&gt;&lt;/p&gt;</oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Context_20260630_20260630_S000006859Member_Credit2_S000006859Summary1Member"
      id="ixv-1006">&lt;p style="margin-top:revert; margin-bottom:revert; font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; font-style:normal;"&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; color:#004C97; font-weight:bold; text-decoration:none;"&gt;Credit:&lt;/span&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:normal; text-decoration:none;"&gt; 
 U.S. government investments generally have the least credit risk but are not completely free of credit 
risk. The Fund may incur losses on debt securities that are inaccurately perceived to present a different 
amount of credit risk by the market, the investment manager or the rating agencies than such securities 
actually do. Any downgrade of securities issued by the U.S. government may result in a downgrade of securities 
issued by its agencies or instrumentalities.&lt;/span&gt;&lt;/p&gt;</oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Context_20260630_20260630_S000006859Member_Income2_S000006859Summary1Member"
      id="ixv-1010">&lt;p style="margin-top:revert; margin-bottom:revert; font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; font-style:normal;"&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; color:#004C97; font-weight:bold; text-decoration:none;"&gt;Income:&lt;/span&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:normal; text-decoration:none;"&gt;  The Fund's distributions 
to shareholders may decline when prevailing interest rates fall, when the Fund experiences defaults on 
debt securities it holds or when the Fund realizes a loss upon the sale of a debt security. Because the 
Fund limits its investments to high-quality, short-term securities, its portfolio generally will earn 
lower yields than a portfolio with lower-quality, longer-term securities subject to more risk.&lt;/span&gt;&lt;/p&gt;</oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Context_20260630_20260630_S000006859Member_USGovernmentSecurities2_S000006859Summary1Member"
      id="ixv-1014">&lt;p style="margin-top:revert; margin-bottom:revert; font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; font-style:normal;"&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; color:#004C97; font-weight:bold; text-decoration:none;"&gt;U.S. 
Government Securities:&lt;/span&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:normal; text-decoration:none;"&gt;  Not all obligations of the U.S. Government, its agencies and instrumentalities 
are backed by the full faith and credit of the United States. Some obligations are backed only by the 
credit of the issuing agency or instrumentality, and in some cases there may be some risk of default 
by the issuer. Government agency or instrumentality issues have different levels of credit support. &lt;/span&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:bold; text-decoration:none;"&gt;U.S. 
government-sponsored entities ("GSEs"), such as Fannie Mae and Freddie Mac, may be chartered by Acts 
of Congress, but their securities are neither issued nor guaranteed by the U.S. government. Although 
the U.S. government has provided financial support to Fannie Mae, Freddie Mac and certain other GSEs 
in the past, no assurance can be given that the U.S. government will continue to do so.&lt;/span&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:normal; text-decoration:none;"&gt; Accordingly, securities 
issued by Fannie Mae and Freddie Mac may involve a risk of non-payment of principal and interest. Investors 
should remember that guarantees of timely repayment of principal and interest do not apply to the market 
prices and yields of the securities or to the net asset value or performance of the Fund, which will 
vary with changes in interest rates and other market conditions.&lt;/span&gt;&lt;/p&gt;</oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Context_20260630_20260630_S000006859Member_RepurchaseAgreements2_S000006859Summary1Member"
      id="ixv-1020">&lt;p style="margin-top:revert; margin-bottom:revert; font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; font-style:normal;"&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; color:#004C97; font-weight:bold; text-decoration:none;"&gt;Repurchase 
Agreements:&lt;/span&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:normal; text-decoration:none;"&gt;  A repurchase agreement exposes the Fund to the risk that the party that sells 
the securities to the Fund may default on its obligation to repurchase such securities.&lt;/span&gt;&lt;/p&gt;</oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Context_20260630_20260630_S000006859Member_Market2_S000006859Summary1Member"
      id="ixv-1024">&lt;p style="margin-top:revert; margin-bottom:revert; font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; font-style:normal;"&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; color:#004C97; font-weight:bold; text-decoration:none;"&gt;Market: 
 &lt;/span&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:normal; text-decoration:none;"&gt;The 
market values of securities or other investments owned by the Fund will go up or down, sometimes rapidly 
or unpredictably. The market value of a security or other investment may be reduced by market activity 
or other results of supply and demand unrelated to the issuer. This is a basic risk associated with all 
investments. When there are more sellers than buyers, prices tend to fall. Likewise, when there are more 
buyers than sellers, prices tend to rise. In addition, the value of the Fund&#x2019;s investments may go up 
or down due to general market or other conditions that are not specifically related to a particular issuer, 
such as: real or perceived adverse economic changes, including widespread liquidity issues and defaults 
in one or more industries; changes in interest, inflation or exchange rates; &lt;/span&gt;&lt;/p&gt;&lt;p style="margin-top:revert; margin-bottom:revert; font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; text-decoration:none;"&gt;unexpected 
natural and man-made world events, such as diseases or disasters; financial, political or social disruptions, 
including terrorism and war; and U.S. trade disputes or other disputes with specific countries that could 
result in additional tariffs, trade barriers and/or investment restrictions in certain securities in 
those countries. Any of these conditions can adversely affect the economic prospects of many companies, 
sectors, nations, regions and the market in general, in ways that cannot necessarily be foreseen.&lt;/p&gt;&lt;p style="margin-top:revert; margin-bottom:revert;font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; text-decoration:none;"&gt;Ongoing 
or threatened armed conflicts throughout the world have caused and could continue to cause significant 
market disruptions and volatility. The hostilities and sanctions resulting from those hostilities could 
have a significant adverse impact on certain investments of the Fund as well as the Fund&#x2019;s performance 
and liquidity.&lt;/p&gt;</oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Context_20260630_20260630_S000006859Member_MasterFeederStructure2_S000006859Summary1Member"
      id="ixv-1049">&lt;p style="margin-top:revert; margin-bottom:revert; font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; font-style:normal;"&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; color:#004C97; font-weight:bold; text-decoration:none;"&gt;Master/Feeder Structure:&lt;/span&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:normal; text-decoration:none;"&gt;  The Fund seeks to 
achieve its investment goal by investing all of its assets in shares of the Master Portfolio. The Master 
Portfolio has the same investment goal and policies as the Fund. The Fund buys shares of the Master Portfolio 
at net asset value. An investment in the Fund is an indirect investment in the Master Portfolio. It is 
possible that the Fund may have to withdraw its investment in the Master Portfolio if the Master Portfolio 
changes its investment goal or if the Fund&#x2019;s board of trustees, at any time, considers it to be in 
the Fund&#x2019;s best interest.&lt;/span&gt;&lt;/p&gt;</oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Context_20260630_20260630_S000006859Member_Management2_S000006859Summary1Member"
      id="ixv-1053">&lt;p style="margin-top:revert; margin-bottom:revert; font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; font-style:normal;"&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; color:#004C97; font-weight:bold; text-decoration:none;"&gt;Management:&lt;/span&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:normal; text-decoration:none;"&gt;  The Fund is subject 
to management risk because it is an actively managed investment portfolio. The investment manager applies 
investment techniques and risk analyses in making investment decisions for the Master Portfolio, but 
there can be no guarantee that these decisions will produce the desired results.&lt;/span&gt;&lt;/p&gt;</oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Context_20260630_20260630_S000006859Member_Cybersecurity2_S000006859Summary1Member"
      id="ixv-1057">&lt;p style="margin-top:revert; margin-bottom:revert; font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; font-style:normal;"&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; color:#004C97; font-weight:bold; text-decoration:none;"&gt;Cybersecurity:&lt;/span&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:normal; text-decoration:none;"&gt; 
 Cybersecurity incidents, both intentional and unintentional, may allow an unauthorized party to gain 
access to Fund assets, Fund or customer data (including private shareholder information), or proprietary 
information, cause the Fund, the investment manager, authorized participants, or index providers (as 
applicable) and listing exchanges, and/or their service providers (including, but not limited to, Fund 
accountants, custodians, sub-custodians, transfer agents and financial intermediaries) to suffer data 
breaches, data corruption or loss of operational functionality or prevent Fund investors from purchasing, 
redeeming shares or receiving distributions. The investment manager has limited ability to prevent or 
mitigate cybersecurity incidents affecting third party service providers, and such third party service 
providers may have limited indemnification obligations to the Fund or the investment manager. Cybersecurity 
incidents may result in financial losses to the Fund and its shareholders, and substantial costs may 
be incurred in an effort to prevent or mitigate future cybersecurity incidents. Issuers of securities 
in which the Fund invests are also subject to cybersecurity risks, and the &lt;/span&gt;&lt;/p&gt;&lt;p style="margin-top:revert; margin-bottom:revert; font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; text-decoration:none;"&gt;value 
of these securities could decline if the issuers experience cybersecurity incidents.&lt;/p&gt;&lt;p style="margin-top:revert; margin-bottom:revert;font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; text-decoration:none;"&gt;Because technology is 
frequently changing (including the development of artificial intelligence and machine learning), new 
ways to carry out cyber attacks are always developing. Therefore, there is a chance that some risks have 
not been identified or prepared for, or that an attack may not be detected, which puts limitations on 
the Fund's ability to plan for or respond to a cyber attack. Like other funds and business enterprises, 
the Fund, the investment manager, and their service providers are subject to the risk of cyber incidents 
occurring from time to time. The rapid development and increasingly widespread use of artificial intelligence 
technologies could increase the effectiveness of cyber attacks and exacerbate the risks.&lt;/p&gt;</oef:RiskTextBlock>
    <oef:BarChartAndPerformanceTableHeading
      contextRef="Context_20260630_20260630_S000006859Member_S000006859Summary1Member"
      id="ixv-11915"> 
 Performance</oef:BarChartAndPerformanceTableHeading>
    <oef:PerformanceNarrativeTextBlock
      contextRef="Context_20260630_20260630_S000006859Member_S000006859Summary1Member"
      id="ixv-1088">&lt;p style="margin-top:revert; margin-bottom:revert; font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; text-decoration:none;"&gt;The 
following bar chart and table provide some indication of the risks of investing in the Fund. The bar 
chart shows changes in the Fund's performance from year to year for Class A shares. The table shows the 
Fund's average annual returns for 1 year, 5 years, 10 years or since inception, as applicable. The Fund's 
past performance is not necessarily an indication of how the Fund will perform in the future. You can 
obtain updated performance information at www.franklintempleton.com or by calling (800) DIAL BEN/342-5236.&lt;/p&gt;</oef:PerformanceNarrativeTextBlock>
    <oef:PerformancePastDoesNotIndicateFuture
      contextRef="Context_20260630_20260630_S000006859Member_S000006859Summary1Member"
      id="ixv-11917">The Fund's 
past performance is not necessarily an indication of how the Fund will perform in the future.</oef:PerformancePastDoesNotIndicateFuture>
    <oef:PerformanceAvailabilityWebSiteAddress
      contextRef="Context_20260630_20260630_S000006859Member_S000006859Summary1Member"
      id="ixv-11918">franklintempleton.com</oef:PerformanceAvailabilityWebSiteAddress>
    <oef:PerformanceAvailabilityPhone
      contextRef="Context_20260630_20260630_S000006859Member_S000006859Summary1Member"
      id="ixv-11919">(800) DIAL BEN/342-5236</oef:PerformanceAvailabilityPhone>
    <oef:BarChartHeading
      contextRef="Context_20260630_20260630_S000006859Member_S000006859Summary1Member"
      id="ixv-11920">Class A Annual Total Returns</oef:BarChartHeading>
    <oef:BarChartClosingTextBlock
      contextRef="Context_20260630_20260630_S000006859Member_S000006859Summary1Member"
      id="ixv-1093">&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse" width="100%"&gt;&lt;tr style="font-size:1pt;"&gt;&lt;td style="width:17.33%;"&gt;&#160;&lt;/td&gt;&lt;td style="width:68%;"&gt;&#160;&lt;/td&gt;&lt;td style="width:14.67%;"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td style="vertical-align:top; border-bottom:0.5pt; border-bottom-style:solid; border-bottom-color:#A7A7A7; border-top:0.5pt; border-top-style:solid; border-top-color:#A7A7A7;"&gt;&lt;p style="font-size:8.5pt; font-family:Sans-Serif; font-style:normal; text-align:left; font-weight:normal; text-decoration:none;"&gt;Best Quarter: &lt;/p&gt;&lt;/td&gt;&lt;td style="vertical-align:top; border-bottom:0.5pt; border-bottom-style:solid; border-bottom-color:#A7A7A7; border-top:0.5pt; border-top-style:solid; border-top-color:#A7A7A7;"&gt;&lt;p style="font-size:8.5pt; font-family:Sans-Serif; font-style:normal; text-align:right; font-weight:normal; text-decoration:none;"&gt;2023, Q4&lt;/p&gt;&lt;/td&gt;&lt;td style="vertical-align:top; border-bottom:0.5pt; border-bottom-style:solid; border-bottom-color:#A7A7A7; border-top:0.5pt; border-top-style:solid; border-top-color:#A7A7A7;"&gt;&lt;p style="font-size:8.5pt; font-family:Sans-Serif; font-style:normal; text-align:right; font-weight:normal; text-decoration:none;"&gt;1.24%&lt;/p&gt;&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td style="vertical-align:top; border-bottom:0.5pt; border-bottom-style:solid; border-bottom-color:#A7A7A7; border-top:0.5pt; border-top-style:solid; border-top-color:#A7A7A7;"&gt;&lt;p style="font-size:8.5pt; font-family:Sans-Serif; font-style:normal; text-align:left; font-weight:normal; text-decoration:none;"&gt;Worst Quarter: &lt;/p&gt;&lt;/td&gt;&lt;td style="vertical-align:top; border-bottom:0.5pt; border-bottom-style:solid; border-bottom-color:#A7A7A7; border-top:0.5pt; border-top-style:solid; border-top-color:#A7A7A7;"&gt;&lt;p style="font-size:8.5pt; font-family:Sans-Serif; font-style:normal; text-align:right; font-weight:normal; text-decoration:none;"&gt;2021, Q3&lt;/p&gt;&lt;/td&gt;&lt;td style="vertical-align:top; border-bottom:0.5pt; border-bottom-style:solid; border-bottom-color:#A7A7A7; border-top:0.5pt; border-top-style:solid; border-top-color:#A7A7A7;"&gt;&lt;p style="font-size:8.5pt; font-family:Sans-Serif; font-style:normal; text-align:right; font-weight:normal; text-decoration:none;"&gt;0.00%&lt;/p&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;
&lt;table cellpadding="2" cellspacing="0" style="border-collapse:collapse" width="100%"&gt;&lt;tr style="font-size:1pt;"&gt;&lt;td style="width:100%;"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td style="vertical-align:top; border-bottom:0.5pt; border-bottom-style:solid; border-bottom-color:#A7A7A7; font-size:1pt;"&gt;&lt;p style="font-size:8.5pt; font-family:Sans-Serif; font-style:normal; text-align:left; font-weight:normal; text-decoration:none;"&gt;As of September 30, 2026, 
the Fund&#x2019;s year-to-date return was 2.41%.&lt;/p&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;</oef:BarChartClosingTextBlock>
    <oef:HighestQuarterlyReturnLabel
      contextRef="Context_20260630_20260630_C000018536Member_S000006859Member_S000006859Summary1Member"
      id="ixv-11921">Best Quarter</oef:HighestQuarterlyReturnLabel>
    <oef:BarChartHighestQuarterlyReturnDate
      contextRef="Context_20260630_20260630_C000018536Member_S000006859Member_S000006859Summary1Member"
      id="ixv-11922">2023-12-31</oef:BarChartHighestQuarterlyReturnDate>
    <oef:BarChartHighestQuarterlyReturn
      contextRef="Context_20260630_20260630_C000018536Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11923"
      unitRef="pure">0.0124</oef:BarChartHighestQuarterlyReturn>
    <oef:LowestQuarterlyReturnLabel
      contextRef="Context_20260630_20260630_C000018536Member_S000006859Member_S000006859Summary1Member"
      id="ixv-11924">Worst Quarter</oef:LowestQuarterlyReturnLabel>
    <oef:BarChartLowestQuarterlyReturnDate
      contextRef="Context_20260630_20260630_C000018536Member_S000006859Member_S000006859Summary1Member"
      id="ixv-11925">2021-09-30</oef:BarChartLowestQuarterlyReturnDate>
    <oef:BarChartLowestQuarterlyReturn
      contextRef="Context_20260630_20260630_C000018536Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11926"
      unitRef="pure">0.0000</oef:BarChartLowestQuarterlyReturn>
    <oef:YearToDateReturnLabel
      contextRef="Context_20260630_20260630_C000018536Member_S000006859Member_S000006859Summary1Member"
      id="ixv-11927">As of September 30, 2026, 
the Fund&#x2019;s year-to-date return was 2.41%.</oef:YearToDateReturnLabel>
    <oef:BarChartYearToDateReturnDate
      contextRef="Context_20260630_20260630_C000018536Member_S000006859Member_S000006859Summary1Member"
      id="ixv-11928">2026-09-30</oef:BarChartYearToDateReturnDate>
    <oef:BarChartYearToDateReturn
      contextRef="Context_20260630_20260630_C000018536Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11929"
      unitRef="pure">0.0241</oef:BarChartYearToDateReturn>
    <oef:PerformanceTableHeading
      contextRef="Context_20260630_20260630_S000006859Member_S000006859Summary1Member"
      id="ixv-11930">Average Annual Total Returns For periods ended December 
31, 2025</oef:PerformanceTableHeading>
    <oef:AvgAnnlRtrPct
      contextRef="Context_20250101_20251231_C000018536Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11931"
      unitRef="pure">0.0381</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Context_20210101_20251231_C000018536Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11932"
      unitRef="pure">0.0287</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Context_20160101_20251231_C000018536Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11933"
      unitRef="pure">0.0177</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Context_20250101_20251231_C000213872Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11934"
      unitRef="pure">0.0314</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Context_20210101_20251231_C000213872Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11935"
      unitRef="pure">0.0239</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Context_20191015_20251231_C000213872Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="_129_"
      unitRef="pure">0.0195</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Context_20250101_20251231_C000213873Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11937"
      unitRef="pure">0.0329</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Context_20210101_20251231_C000213873Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11938"
      unitRef="pure">0.0250</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Context_20191015_20251231_C000213873Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="_132_"
      unitRef="pure">0.0205</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Context_20250101_20251231_C000128781Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11940"
      unitRef="pure">0.0382</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Context_20210101_20251231_C000128781Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11941"
      unitRef="pure">0.0289</oef:AvgAnnlRtrPct>
    <oef:AvgAnnlRtrPct
      contextRef="Context_20160101_20251231_C000128781Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-11942"
      unitRef="pure">0.0181</oef:AvgAnnlRtrPct>
    <oef:RiskReturnHeading
      contextRef="Context_20260630_20260630_S000006859Member_S000006859Summary2Member"
      id="ixv-11943">FRANKLIN U.S. GOVERNMENT 
MONEY FUND</oef:RiskReturnHeading>
    <oef:ProspectusDate contextRef="Context_20260630_20260630" id="ixv-11944">2026-11-01</oef:ProspectusDate>
    <oef:ObjectiveHeading
      contextRef="Context_20260630_20260630_S000006859Member_S000006859Summary2Member"
      id="ixv-11945"> 
 Investment Goal</oef:ObjectiveHeading>
    <oef:ObjectivePrimaryTextBlock
      contextRef="Context_20260630_20260630_S000006859Member_S000006859Summary2Member"
      id="ixv-4488">&lt;p style="margin-top:revert; margin-bottom:revert; font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; text-decoration:none;"&gt;To 
provide investors with as high a level of current income as is consistent with the preservation of shareholders&#x2019; 
capital and liquidity. The Fund also tries to maintain a stable $1.00 share price. &lt;/p&gt;</oef:ObjectivePrimaryTextBlock>
    <oef:ExpenseHeading
      contextRef="Context_20260630_20260630_S000006859Member_S000006859Summary2Member"
      id="ixv-11947">  
Fees and Expenses of the Fund</oef:ExpenseHeading>
    <oef:ExpenseNarrativeTextBlock
      contextRef="Context_20260630_20260630_S000006859Member_S000006859Summary2Member"
      id="ixv-4496">&lt;p style="margin-top:revert; margin-bottom:revert; font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; text-decoration:none;"&gt;These tables describe the fees and expenses 
that you may pay if you buy, hold and sell Class P1 shares of the Fund. Please note that the tables and 
examples below do not reflect any transaction fees that may be charged by financial intermediaries, or 
commissions that a shareholder may be required to pay directly to its financial intermediary. Information 
about sales charge discounts and waivers for purchases of shares through specific financial intermediaries 
is set forth in Appendix A &#x2013; &#x201c;Intermediary Sales Charge Discounts and Waivers&#x201d; to the Fund&#x2019;s 
prospectus.&lt;/p&gt;</oef:ExpenseNarrativeTextBlock>
    <oef:ShareholderFeesCaption
      contextRef="Context_20260630_20260630_S000006859Member_S000006859Summary2Member"
      id="ixv-11949">Shareholder Fees</oef:ShareholderFeesCaption>
    <oef:MaximumSalesChargeImposedOnPurchasesOverOfferingPrice
      contextRef="Context_20260630_20260630_C000253579Member_S000006859Member_S000006859Summary2Member"
      decimals="INF"
      id="ixv-11950"
      unitRef="pure">0</oef:MaximumSalesChargeImposedOnPurchasesOverOfferingPrice>
    <oef:MaximumDeferredSalesChargeOverOfferingPrice
      contextRef="Context_20260630_20260630_C000253579Member_S000006859Member_S000006859Summary2Member"
      decimals="INF"
      id="ixv-11951"
      unitRef="pure">0</oef:MaximumDeferredSalesChargeOverOfferingPrice>
    <oef:OperatingExpensesCaption
      contextRef="Context_20260630_20260630_S000006859Member_S000006859Summary2Member"
      id="ixv-11952">Annual Fund 
Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)</oef:OperatingExpensesCaption>
    <oef:ManagementFeesOverAssets
      contextRef="Context_20260630_20260630_C000253579Member_S000006859Member_S000006859Summary2Member"
      decimals="INF"
      id="ixv-11953"
      unitRef="pure">0.0015</oef:ManagementFeesOverAssets>
    <oef:DistributionAndService12b1FeesOverAssets
      contextRef="Context_20260630_20260630_C000253579Member_S000006859Member_S000006859Summary2Member"
      decimals="INF"
      id="ixv-11954"
      unitRef="pure">0.0010</oef:DistributionAndService12b1FeesOverAssets>
    <oef:OtherExpensesOverAssets
      contextRef="Context_20260630_20260630_C000253579Member_S000006859Member_S000006859Summary2Member"
      decimals="INF"
      id="ixv-11955"
      unitRef="pure">0.0036</oef:OtherExpensesOverAssets>
    <oef:ExpensesOverAssets
      contextRef="Context_20260630_20260630_C000253579Member_S000006859Member_S000006859Summary2Member"
      decimals="INF"
      id="_151_"
      unitRef="pure">0.0061</oef:ExpensesOverAssets>
    <oef:ExpenseExampleHeading
      contextRef="Context_20260630_20260630_S000006859Member_S000006859Summary2Member"
      id="ixv-11957">Example</oef:ExpenseExampleHeading>
    <oef:ExpenseExampleNarrativeTextBlock
      contextRef="Context_20260630_20260630_S000006859Member_S000006859Summary2Member"
      id="ixv-4587">&lt;p style="margin-top:revert; margin-bottom:revert; font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; text-decoration:none;"&gt;This 
Example is intended to help you compare the cost of investing in the Fund with the cost of investing 
in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated 
and then redeem all of your shares at the end of the period. The Example also assumes that your investment 
has a 5% return each year and that the Fund's operating expenses remain the same. Although your actual 
costs may be higher or lower, based on these assumptions your costs would be:&lt;/p&gt;
</oef:ExpenseExampleNarrativeTextBlock>
    <oef:ExpenseExampleYear01
      contextRef="Context_20260630_20260630_C000253579Member_S000006859Member_S000006859Summary2Member"
      decimals="INF"
      id="ixv-11958"
      unitRef="usd">62</oef:ExpenseExampleYear01>
    <oef:ExpenseExampleYear03
      contextRef="Context_20260630_20260630_C000253579Member_S000006859Member_S000006859Summary2Member"
      decimals="INF"
      id="ixv-11959"
      unitRef="usd">195</oef:ExpenseExampleYear03>
    <oef:ExpenseExampleYear05
      contextRef="Context_20260630_20260630_C000253579Member_S000006859Member_S000006859Summary2Member"
      decimals="INF"
      id="ixv-11960"
      unitRef="usd">340</oef:ExpenseExampleYear05>
    <oef:ExpenseExampleYear10
      contextRef="Context_20260630_20260630_C000253579Member_S000006859Member_S000006859Summary2Member"
      decimals="INF"
      id="ixv-11961"
      unitRef="usd">762</oef:ExpenseExampleYear10>
    <oef:StrategyHeading
      contextRef="Context_20260630_20260630_S000006859Member_S000006859Summary2Member"
      id="ixv-11962">  
Principal Investment Strategies</oef:StrategyHeading>
    <oef:StrategyNarrativeTextBlock
      contextRef="Context_20260630_20260630_S000006859Member_S000006859Summary2Member"
      id="ixv-4685">&lt;p style="margin-top:revert; margin-bottom:revert; font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; text-decoration:none;"&gt;The Fund is a &#x201c;feeder fund&#x201d; that invests, 
through the Master Portfolio, at least 99.5% of its total assets in Government securities, cash and repurchase 
agreements collateralized fully by Government securities or cash. In addition, under normal circumstances, 
the Fund invests, through the Master Portfolio, at least 80% of its net assets in Government securities 
and repurchase agreements collateralized fully by Government securities. In contrast to the Fund's 99.5% 
policy, the Fund's 80% policy does not include cash. For purposes of these policies, &#x201c;Government securities&#x201d; 
means any securities issued or guaranteed as to principal or interest by the United States, or by a person 
controlled or supervised by and acting as an instrumentality of the Government of the United States pursuant 
to authority granted by the Congress of the United States; or any certificate of deposit for any of the 
foregoing. Government securities include those issued by government agencies or instrumentalities, such 
as the Federal National Mortgage Association (Fannie Mae), Federal Home Loan Mortgage Corporation (Freddie 
Mac), Federal Home Loan Banks and Federal Farm Credit Banks, whose securities are neither issued nor 
guaranteed by the U.S. Government. The Fund intends to be a &#x201c;Government money market fund,&#x201d; as such 
term is defined in or interpreted under Rule 2a-7 under the Investment Company Act of 1940. Shareholders 
will be given at least 60 days&#x2019; advance notice of any change to the 99.5% and 80% policies.&lt;/p&gt;&lt;p style="margin-top:revert; margin-bottom:revert; font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; text-decoration:none;"&gt;The Fund uses the amortized 
cost method of valuation to seek to maintain a stable $1.00 share price.&lt;/p&gt;&lt;p style="margin-top:revert; margin-bottom:revert; font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; text-decoration:none;"&gt;Unless the context otherwise 
requires, references to the Fund&#x2019;s investments refer to those investments of the Master Portfolio to 
which the Fund is exposed and references to the investment manager or the Fund&#x2019;s investment manager 
refer to the Master Portfolio&#x2019;s investment manager.&lt;/p&gt;&lt;p style="margin-top:revert; margin-bottom:revert; font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; text-decoration:none;"&gt;The Fund invests in:&lt;/p&gt;&lt;p style="margin-top:revert; margin-bottom:revert; font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; font-style:normal;"&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:bold; text-decoration:none;"&gt;U.S. government securities&lt;/span&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:normal; text-decoration:none;"&gt; 
which may include fixed, floating and variable rate securities.&lt;/span&gt;&lt;/p&gt;&lt;p style="margin-top:revert; margin-bottom:revert; font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; font-style:normal;"&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:bold; text-decoration:none;"&gt;Repurchase agreements&lt;/span&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:normal; text-decoration:none;"&gt; 
which are agreements by the Fund to buy Government securities from a broker-dealer or other counterparty 
and then to sell the securities back to such counterparty on an agreed upon date (generally, less than 
seven days) at a higher price, which reflects prevailing short-term interest rates.&lt;/span&gt;&lt;/p&gt;&lt;p style="margin-top:revert; margin-bottom:revert; font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; font-style:normal;"&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:bold; text-decoration:none;"&gt;Portfolio 
maturity and quality&lt;/span&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:normal; text-decoration:none;"&gt; The Fund only buys securities that the investment manager determines present 
minimal credit risks. The Fund maintains a dollar-weighted average portfolio maturity of 60 calendar 
days or less, maintains a dollar-weighted average life for its portfolio of 120 calendar days or less, 
and only buys securities that mature or are deemed to mature in 397 calendar days or less.&lt;/span&gt;&lt;/p&gt;</oef:StrategyNarrativeTextBlock>
    <fnd:NmRule35d1EightyPctInvstmntPlcyTextBlock
      contextRef="Context_20260630_20260630_S000006859Member_S000006859Summary2Member"
      id="ixv-11964">In addition, under normal circumstances, 
the Fund invests, through the Master Portfolio, at least 80% of its net assets in Government securities 
and repurchase agreements collateralized fully by Government securities</fnd:NmRule35d1EightyPctInvstmntPlcyTextBlock>
    <fnd:NmRule35d1TermDfnSmryTextBlock
      contextRef="Context_20260630_20260630_S000006859Member_S000006859Summary2Member"
      id="ixv-11965"> In contrast to the Fund's 99.5% 
policy, the Fund's 80% policy does not include cash. For purposes of these policies, &#x201c;Government securities&#x201d; 
means any securities issued or guaranteed as to principal or interest by the United States, or by a person 
controlled or supervised by and acting as an instrumentality of the Government of the United States pursuant 
to authority granted by the Congress of the United States; or any certificate of deposit for any of the 
foregoing. Government securities include those issued by government agencies or instrumentalities, such 
as the Federal National Mortgage Association (Fannie Mae), Federal Home Loan Mortgage Corporation (Freddie 
Mac), Federal Home Loan Banks and Federal Farm Credit Banks, whose securities are neither issued nor 
guaranteed by the U.S. Government. The Fund intends to be a &#x201c;Government money market fund,&#x201d; as such 
term is defined in or interpreted under Rule 2a-7 under the Investment Company Act of 1940. Shareholders 
will be given at least 60 days&#x2019; advance notice of any change to the 99.5% and 80% policies.</fnd:NmRule35d1TermDfnSmryTextBlock>
    <oef:RiskTextBlock
      contextRef="Context_20260630_20260630_S000006859Member_PrincipalRisks2_S000006859Summary2Member"
      id="ixv-4718">&lt;p style="margin-top:revert; margin-bottom:revert; font-size:13.0pt; font-family:Arial; text-align:left; color:#004C97; font-weight:normal; font-style:normal;"&gt;&lt;span style="font-size:4.0pt; font-family:Arial; font-style:normal; color:#004C97; font-weight:normal; text-decoration:none;"&gt; 
&lt;/span&gt;&lt;a href="" id="x4x3"&gt;&lt;/a&gt;&lt;span style="font-size:13.0pt; font-family:Arial; font-style:normal; color:#004C97; font-weight:normal; text-decoration:none;"&gt; &lt;/span&gt;&lt;span style="font-size:13.0pt; font-family:Arial; font-style:normal; color:#004C97; font-weight:normal; text-decoration:none;"&gt;Principal Risks&lt;/span&gt;&lt;/p&gt;&lt;p style="margin-top:revert; margin-bottom:revert; font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; text-decoration:none;"&gt;You 
could lose money by investing in the Fund. Although the Fund seeks to preserve the value of your investment 
at $1.00 per share, it cannot guarantee it will do so. An investment in the Fund is not a bank account 
and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government 
agency. The Fund&#x2019;s sponsor is not required to reimburse the Fund for losses, and you should not expect 
that the sponsor will provide financial support to the Fund at any time, including during periods of 
market stress.&lt;/p&gt;</oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Context_20260630_20260630_S000006859Member_RiskLoseMoneyMember_S000006859Summary2Member"
      id="ixv-11966">You 
could lose money by investing in the Fund.</oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Context_20260630_20260630_S000006859Member_RiskMoneyMarketFundMayNotPreserveDollarMember_S000006859Summary2Member"
      id="ixv-11967">Although the Fund seeks to preserve the value of your investment 
at $1.00 per share, it cannot guarantee it will do so.</oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Context_20260630_20260630_S000006859Member_RiskNotInsuredMember_S000006859Summary2Member"
      id="ixv-11968">An investment in the Fund is not a bank account 
and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government 
agency.</oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Context_20260630_20260630_S000006859Member_InterestRate2_S000006859Summary2Member"
      id="ixv-4725">&lt;p style="margin-top:revert; margin-bottom:revert; font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; font-style:normal;"&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; color:#004C97; font-weight:bold; text-decoration:none;"&gt;Interest Rate:&lt;/span&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:normal; text-decoration:none;"&gt;  When interest rates rise, debt security 
prices generally fall. The opposite is also generally true: debt security prices rise when interest rates 
fall. Interest rate changes are influenced by a number of factors, including government policy, monetary 
policy, inflation expectations, perceptions of risk, and supply of and demand for debt securities. The 
Fund's yield will vary. A low interest or negative rate environment may prevent the Fund from providing 
a positive yield or paying Fund expenses out of current income and could impair the Fund's ability to 
maintain a stable net asset value. A sharp and unexpected rise in interest rates could cause the Fund's 
share price to drop below a dollar. In general, securities with longer maturities or durations are more 
sensitive to these interest rate changes. &lt;/span&gt;&lt;/p&gt;</oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Context_20260630_20260630_S000006859Member_Credit2_S000006859Summary2Member"
      id="ixv-4729">&lt;p style="margin-top:revert; margin-bottom:revert; font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; font-style:normal;"&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; color:#004C97; font-weight:bold; text-decoration:none;"&gt;Credit:&lt;/span&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:normal; text-decoration:none;"&gt;  U.S. government investments generally 
have the least credit risk but are not completely free of credit risk. The Fund may incur losses on debt 
securities that are inaccurately perceived to present a different amount of credit risk by the market, 
the investment manager or the rating agencies than such securities actually do. Any downgrade of securities 
issued by the U.S. government may result in a downgrade of securities issued by its agencies or instrumentalities.&lt;/span&gt;&lt;/p&gt;</oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Context_20260630_20260630_S000006859Member_Income2_S000006859Summary2Member"
      id="ixv-4733">&lt;p style="margin-top:revert; margin-bottom:revert; font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; font-style:normal;"&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; color:#004C97; font-weight:bold; text-decoration:none;"&gt;Income:&lt;/span&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:normal; text-decoration:none;"&gt; 
 The Fund's distributions to shareholders may decline when prevailing interest rates fall, when the Fund 
experiences defaults on debt securities it holds or when the Fund realizes a loss upon the sale of a 
debt security. Because the Fund limits its investments to high-quality, short-term securities, its portfolio 
generally will earn lower yields than a portfolio with lower-quality, longer-term securities subject 
to more risk.&lt;/span&gt;&lt;/p&gt;</oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Context_20260630_20260630_S000006859Member_USGovernmentSecurities2_S000006859Summary2Member"
      id="ixv-4737">&lt;p style="margin-top:revert; margin-bottom:revert; font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; font-style:normal;"&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; color:#004C97; font-weight:bold; text-decoration:none;"&gt;U.S. Government Securities:&lt;/span&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:normal; text-decoration:none;"&gt;  Not all obligations 
of the U.S. Government, its agencies and instrumentalities are backed by the full faith and credit of 
the United &lt;/span&gt;&lt;/p&gt;&lt;p style="margin-top:revert; margin-bottom:revert; font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; font-style:normal;"&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:normal; text-decoration:none;"&gt;States. 
Some obligations are backed only by the credit of the issuing agency or instrumentality, and in some 
cases there may be some risk of default by the issuer. Government agency or instrumentality issues have 
different levels of credit support. &lt;/span&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:bold; text-decoration:none;"&gt;U.S. government-sponsored entities ("GSEs"), such as Fannie 
Mae and Freddie Mac, may be chartered by Acts of Congress, but their securities are neither issued nor 
guaranteed by the U.S. government. Although the U.S. government has provided financial support to Fannie 
Mae, Freddie Mac and certain other GSEs in the past, no assurance can be given that the U.S. government 
will continue to do so.&lt;/span&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:normal; text-decoration:none;"&gt; Accordingly, securities issued by Fannie Mae and Freddie Mac may involve a risk 
of non-payment of principal and interest. Investors should remember that guarantees of timely repayment 
of principal and interest do not apply to the market prices and yields of the securities or to the net 
asset value or performance of the Fund, which will vary with changes in interest rates and other market 
conditions.&lt;/span&gt;&lt;/p&gt;</oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Context_20260630_20260630_S000006859Member_RepurchaseAgreements2_S000006859Summary2Member"
      id="ixv-4764">&lt;p style="margin-top:revert; margin-bottom:revert; font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; font-style:normal;"&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; color:#004C97; font-weight:bold; text-decoration:none;"&gt;Repurchase Agreements:&lt;/span&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:normal; text-decoration:none;"&gt;  A repurchase agreement exposes the Fund 
to the risk that the party that sells the securities to the Fund may default on its obligation to repurchase 
such securities.&lt;/span&gt;&lt;/p&gt;</oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Context_20260630_20260630_S000006859Member_Market2_S000006859Summary2Member"
      id="ixv-4768">&lt;p style="margin-top:revert; margin-bottom:revert; font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; font-style:normal;"&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; color:#004C97; font-weight:bold; text-decoration:none;"&gt;Market:  &lt;/span&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:normal; text-decoration:none;"&gt;The market values of securities or other 
investments owned by the Fund will go up or down, sometimes rapidly or unpredictably. The market value 
of a security or other investment may be reduced by market activity or other results of supply and demand 
unrelated to the issuer. This is a basic risk associated with all investments. When there are more sellers 
than buyers, prices tend to fall. Likewise, when there are more buyers than sellers, prices tend to rise. 
In addition, the value of the Fund&#x2019;s investments may go up or down due to general market or other conditions 
that are not specifically related to a particular issuer, such as: real or perceived adverse economic 
changes, including widespread liquidity issues and defaults in one or more industries; changes in interest, 
inflation or exchange rates; unexpected natural and man-made world events, such as diseases or disasters; 
financial, political or social disruptions, including terrorism and war; and U.S. trade disputes or other 
disputes with specific countries that could result in additional tariffs, trade barriers and/or investment 
restrictions in certain securities in those countries. Any of these conditions can adversely affect the 
economic prospects of many companies, sectors, nations, regions and the market in general, in ways that 
cannot necessarily be foreseen.&lt;/span&gt;&lt;/p&gt;&lt;p style="margin-top:revert; margin-bottom:revert;font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; text-decoration:none;"&gt;Ongoing or threatened armed conflicts throughout the world 
have caused and could continue to cause significant market disruptions and volatility. The hostilities 
and sanctions resulting from those hostilities could have a significant adverse impact on certain investments 
of the Fund as well as the Fund&#x2019;s performance and liquidity.&lt;/p&gt;</oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Context_20260630_20260630_S000006859Member_MasterFeederStructure2_S000006859Summary2Member"
      id="ixv-4773">&lt;p style="margin-top:revert; margin-bottom:revert; font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; font-style:normal;"&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; color:#004C97; font-weight:bold; text-decoration:none;"&gt;Master/Feeder 
Structure:&lt;/span&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:normal; text-decoration:none;"&gt;  The Fund seeks to achieve its investment goal by investing all of its assets 
in shares of the Master Portfolio. The Master Portfolio has &lt;/span&gt;&lt;/p&gt;&lt;p style="margin-top:revert; margin-bottom:revert; font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; text-decoration:none;"&gt;the 
same investment goal and policies as the Fund. The Fund buys shares of the Master Portfolio at net asset 
value. An investment in the Fund is an indirect investment in the Master Portfolio. It is possible that 
the Fund may have to withdraw its investment in the Master Portfolio if the Master Portfolio changes 
its investment goal or if the Fund&#x2019;s board of trustees, at any time, considers it to be in the Fund&#x2019;s 
best interest.&lt;/p&gt;</oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Context_20260630_20260630_S000006859Member_Management2_S000006859Summary2Member"
      id="ixv-4797">&lt;p style="margin-top:revert; margin-bottom:revert; font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; font-style:normal;"&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; color:#004C97; font-weight:bold; text-decoration:none;"&gt;Management:&lt;/span&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:normal; text-decoration:none;"&gt;  The Fund is subject to management risk 
because it is an actively managed investment portfolio. The investment manager applies investment techniques 
and risk analyses in making investment decisions for the Master Portfolio, but there can be no guarantee 
that these decisions will produce the desired results.&lt;/span&gt;&lt;/p&gt;</oef:RiskTextBlock>
    <oef:RiskTextBlock
      contextRef="Context_20260630_20260630_S000006859Member_Cybersecurity2_S000006859Summary2Member"
      id="ixv-4801">&lt;p style="margin-top:revert; margin-bottom:revert; font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; font-style:normal;"&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; color:#004C97; font-weight:bold; text-decoration:none;"&gt;Cybersecurity:&lt;/span&gt;&lt;span style="font-size:9.0pt; font-family:Arial; font-style:normal; font-weight:normal; text-decoration:none;"&gt; 
 Cybersecurity incidents, both intentional and unintentional, may allow an unauthorized party to gain 
access to Fund assets, Fund or customer data (including private shareholder information), or proprietary 
information, cause the Fund, the investment manager, authorized participants, or index providers (as 
applicable) and listing exchanges, and/or their service providers (including, but not limited to, Fund 
accountants, custodians, sub-custodians, transfer agents and financial intermediaries) to suffer data 
breaches, data corruption or loss of operational functionality or prevent Fund investors from purchasing, 
redeeming shares or receiving distributions. The investment manager has limited ability to prevent or 
mitigate cybersecurity incidents affecting third party service providers, and such third party service 
providers may have limited indemnification obligations to the Fund or the investment manager. Cybersecurity 
incidents may result in financial losses to the Fund and its shareholders, and substantial costs may 
be incurred in an effort to prevent or mitigate future cybersecurity incidents. Issuers of securities 
in which the Fund invests are also subject to cybersecurity risks, and the value of these securities 
could decline if the issuers experience cybersecurity incidents.&lt;/span&gt;&lt;/p&gt;&lt;p style="margin-top:revert; margin-bottom:revert;font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; text-decoration:none;"&gt;Because technology is 
frequently changing (including the development of artificial intelligence and machine learning), new 
ways to carry out cyber attacks are always developing. Therefore, there is a chance that some risks have 
not been identified or prepared for, or that an attack may not be detected, which puts limitations on 
the Fund's ability to plan for or respond to a cyber attack. Like other funds and business enterprises, 
the Fund, the investment manager, and their service providers are subject to the risk of cyber incidents 
occurring from time to time. The rapid development and increasingly widespread use of artificial intelligence 
technologies could increase the effectiveness of cyber attacks and exacerbate the risks.&lt;/p&gt;
</oef:RiskTextBlock>
    <oef:BarChartAndPerformanceTableHeading
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      id="ixv-11969"> 
 Performance</oef:BarChartAndPerformanceTableHeading>
    <oef:PerformanceNarrativeTextBlock
      contextRef="Context_20260630_20260630_S000006859Member_S000006859Summary2Member"
      id="ixv-4830">&lt;p style="margin-top:revert; margin-bottom:revert;font-size:9.0pt; font-family:Arial; text-align:left; font-weight:normal; text-decoration:none;"&gt;The 
following bar chart and table provide some indication of the risks of investing in the Fund. The bar 
chart shows changes in the Fund's performance from year to year for Class P1 shares. The table shows 
the Fund's average annual returns for 1 year, 5 years, 10 years or since inception, as applicable. The 
Fund's past performance is not necessarily an indication of how the Fund will perform in the future. 
You can obtain updated performance information at www.franklintempleton.com or by calling (800) DIAL 
BEN/342-5236.&lt;/p&gt;</oef:PerformanceNarrativeTextBlock>
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Fund's past performance is not necessarily an indication of how the Fund will perform in the future.</oef:PerformancePastDoesNotIndicateFuture>
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      contextRef="Context_20260630_20260630_S000006859Member_S000006859Summary2Member"
      id="ixv-11972">franklintempleton.com</oef:PerformanceAvailabilityWebSiteAddress>
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      contextRef="Context_20260630_20260630_S000006859Member_S000006859Summary2Member"
      id="ixv-11973">Class P1 Annual Total Returns</oef:BarChartHeading>
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      contextRef="Context_20260630_20260630_S000006859Member_S000006859Summary2Member"
      id="ixv-4835">&lt;table cellpadding="0" cellspacing="0" style="border-collapse:collapse" width="100%"&gt;&lt;tr style="font-size:1pt;"&gt;&lt;td style="width:17.33%;"&gt;&#160;&lt;/td&gt;&lt;td style="width:68%;"&gt;&#160;&lt;/td&gt;&lt;td style="width:14.67%;"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td style="vertical-align:top; border-bottom:0.5pt; border-bottom-style:solid; border-bottom-color:#A7A7A7; border-top:0.5pt; border-top-style:solid; border-top-color:#A7A7A7;"&gt;&lt;p style="font-size:8.5pt; font-family:Sans-Serif; font-style:normal; text-align:left; font-weight:normal; text-decoration:none;"&gt;Best Quarter: &lt;/p&gt;&lt;/td&gt;&lt;td style="vertical-align:top; border-bottom:0.5pt; border-bottom-style:solid; border-bottom-color:#A7A7A7; border-top:0.5pt; border-top-style:solid; border-top-color:#A7A7A7;"&gt;&lt;p style="font-size:8.5pt; font-family:Sans-Serif; font-style:normal; text-align:right; font-weight:normal; text-decoration:none;"&gt;2025, Q3&lt;/p&gt;&lt;/td&gt;&lt;td style="vertical-align:top; border-bottom:0.5pt; border-bottom-style:solid; border-bottom-color:#A7A7A7; border-top:0.5pt; border-top-style:solid; border-top-color:#A7A7A7;"&gt;&lt;p style="font-size:8.5pt; font-family:Sans-Serif; font-style:normal; text-align:right; font-weight:normal; text-decoration:none;"&gt;0.94%&lt;/p&gt;&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td style="vertical-align:top; border-bottom:0.5pt; border-bottom-style:solid; border-bottom-color:#A7A7A7; border-top:0.5pt; border-top-style:solid; border-top-color:#A7A7A7;"&gt;&lt;p style="font-size:8.5pt; font-family:Sans-Serif; font-style:normal; text-align:left; font-weight:normal; text-decoration:none;"&gt;Worst Quarter: &lt;/p&gt;&lt;/td&gt;&lt;td style="vertical-align:top; border-bottom:0.5pt; border-bottom-style:solid; border-bottom-color:#A7A7A7; border-top:0.5pt; border-top-style:solid; border-top-color:#A7A7A7;"&gt;&lt;p style="font-size:8.5pt; font-family:Sans-Serif; font-style:normal; text-align:right; font-weight:normal; text-decoration:none;"&gt;2025, Q4&lt;/p&gt;&lt;/td&gt;&lt;td style="vertical-align:top; border-bottom:0.5pt; border-bottom-style:solid; border-bottom-color:#A7A7A7; border-top:0.5pt; border-top-style:solid; border-top-color:#A7A7A7;"&gt;&lt;p style="font-size:8.5pt; font-family:Sans-Serif; font-style:normal; text-align:right; font-weight:normal; text-decoration:none;"&gt;0.86%&lt;/p&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;&lt;table cellpadding="2" cellspacing="0" style="border-collapse:collapse" width="100%"&gt;&lt;tr style="font-size:1pt;"&gt;&lt;td style="width:100%;"&gt;&#160;&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td style="vertical-align:top; border-bottom:0.5pt; border-bottom-style:solid; border-bottom-color:#A7A7A7; font-size:1pt;"&gt;&lt;p style="font-size:8.5pt; font-family:Sans-Serif; font-style:normal; text-align:left; font-weight:normal; text-decoration:none;"&gt;As of September 30, 2026, 
the Fund&#x2019;s year-to-date return was 2.33%.&lt;/p&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;</oef:BarChartClosingTextBlock>
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      contextRef="Context_20260630_20260630_C000253579Member_S000006859Member_S000006859Summary2Member"
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      unitRef="pure">0.0094</oef:BarChartHighestQuarterlyReturn>
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    <oef:BarChartLowestQuarterlyReturnDate
      contextRef="Context_20260630_20260630_C000253579Member_S000006859Member_S000006859Summary2Member"
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      contextRef="Context_20260630_20260630_C000253579Member_S000006859Member_S000006859Summary2Member"
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      unitRef="pure">0.0086</oef:BarChartLowestQuarterlyReturn>
    <oef:YearToDateReturnLabel
      contextRef="Context_20260630_20260630_C000253579Member_S000006859Member_S000006859Summary2Member"
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the Fund&#x2019;s year-to-date return was 2.33%.</oef:YearToDateReturnLabel>
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      contextRef="Context_20260630_20260630_C000253579Member_S000006859Member_S000006859Summary2Member"
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      unitRef="pure">0.0233</oef:BarChartYearToDateReturn>
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      id="ixv-11983">Average Annual Total Returns For periods ended December 
31, 2025</oef:PerformanceTableHeading>
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      contextRef="Context_20250101_20251231_C000253579Member_S000006859Member_S000006859Summary2Member"
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      id="ixv-11984"
      unitRef="pure">0.0370</oef:AvgAnnlRtrPct>
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      contextRef="Context_20240904_20251231_C000253579Member_S000006859Member_S000006859Summary2Member"
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      id="_200_"
      unitRef="pure">0.0386</oef:AvgAnnlRtrPct>
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    <dei:DocumentPeriodEndDate contextRef="Context_20260630_20260630" id="ixv-11989">2026-06-30</dei:DocumentPeriodEndDate>
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    <oef:AnnlRtrPct
      contextRef="Context_20171231_20171231_C000018536Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
      id="ixv-12602"
      unitRef="pure">0.0032</oef:AnnlRtrPct>
    <oef:AnnlRtrPct
      contextRef="Context_20181231_20181231_C000018536Member_S000006859Member_S000006859Summary1Member"
      decimals="INF"
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    <oef:AnnlRtrPct
      contextRef="Context_20191231_20191231_C000018536Member_S000006859Member_S000006859Summary1Member"
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      contextRef="Context_20201231_20201231_C000018536Member_S000006859Member_S000006859Summary1Member"
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      contextRef="Context_20260630_20260630_C000018536Member_S000006859Member_S000006859Summary1Member"
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      contextRef="Context_20260630_20260630_C000213873Member_S000006859Member_S000006859Summary1Member"
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      contextRef="Context_20260630_20260630_C000128781Member_S000006859Member_S000006859Summary1Member"
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    <oef:PerfInceptionDate
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      id="ixv-12616">2019-10-15</oef:PerfInceptionDate>
    <oef:PerfInceptionDate
      contextRef="Context_20191015_20251231_C000213873Member_S000006859Member_S000006859Summary1Member"
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    <oef:PerfInceptionDate
      contextRef="Context_20240904_20251231_C000253579Member_S000006859Member_S000006859Summary2Member"
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    <link:footnoteLink
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        <link:loc xlink:href="#_40_" xlink:label="_40_" xlink:type="locator"/>
        <link:loc xlink:href="#_41_" xlink:label="_41_" xlink:type="locator"/>
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The fees and expenses shown in the table and included in the example below reflect the fees and expenses 
of both the Fund and The U.S. Government Money Market Portfolio (Master Portfolio), in which the Fund 
seeks to invest all of its assets in order to pursue its investment goal.</xhtml:span></link:footnote>
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        <link:loc xlink:href="#_43_" xlink:label="_43_" xlink:type="locator"/>
        <link:footnote id="fn2_" xlink:label="fn2_" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:span style="font-size:7.0pt; font-family:Sans-Serif; font-style:normal; font-weight:normal; text-decoration:none;"> 
Transfer agency fees on Class R6 shares of the Fund have been capped so that transfer agency fees for 
that class do not exceed 0.02% until October 31, 2027. During its term, this fee agreement may not be 
terminated or amended without approval of the board of trustees except to add series and classes, to 
reflect the extension of termination dates or to lower the waiver and expense limitation (which would 
result in lower fees for shareholders).</xhtml:span></link:footnote>
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          xlink:from="_44_"
          xlink:to="fn2_"
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          xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"
          xlink:from="_46_"
          xlink:to="fn2_"
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        <link:loc
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        <link:loc
          xlink:href="#_129_"
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        <link:footnote id="fn3_" xlink:label="fn3_" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:p style="font-size:7.0pt; font-family:Sans-Serif; font-style:normal; text-align:left; font-weight:normal; text-decoration:none;">Since inception October 15, 2019.</xhtml:p></link:footnote>
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        <link:loc
          xlink:href="#_151_"
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        <link:footnote id="fn4_" xlink:label="fn4_" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:span style="font-size:7.0pt; font-family:Sans-Serif; font-style:normal; font-weight:normal; text-decoration:none;"> 
The fees and expenses shown in the table and included in the example below reflect the fees and expenses 
of both the Fund and The U.S. Government Money Market Portfolio (Master Portfolio), in which the Fund 
seeks to invest all of its assets in order to pursue its investment goal.</xhtml:span></link:footnote>
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          xlink:to="fn4_"
          xlink:type="arc"/>
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        <link:footnote id="fn5_" xlink:label="fn5_" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US"><xhtml:p style="font-size:7.0pt; font-family:Sans-Serif; font-style:normal; text-align:left; font-weight:normal; text-decoration:none;">Since inception September 4, 2024.</xhtml:p></link:footnote>
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