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    <dei:EntityRegistrantName contextRef="AsOf2022-05-27">Putnam Tax Exempt Income Fund</dei:EntityRegistrantName>
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    <dei:DocumentPeriodEndDate contextRef="AsOf2022-05-27">2022-01-30</dei:DocumentPeriodEndDate>
    <rr:ShareholderFeesTableTextBlock contextRef="AsOf2022-05-27_custom_S000006568Member">~ http://putnam.com/role/ShareholderFeesData column period compact * column dei_LegalEntityAxis compact PTAEX_S000006568Member column rr_ProspectusShareClassAxis compact * row primary compact * ~</rr:ShareholderFeesTableTextBlock>
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    <rr:ExpenseNarrativeTextBlock contextRef="AsOf2022-05-27_custom_S000006568Member">&lt;p id="xdx_A87_err--ExpenseNarrativeTextBlock_zHeHKknctdT1" style="font: 12pt Times New Roman, Times, Serif; margin: 0"&gt;&lt;span style="font-size: 11pt"&gt;The following tables describe the fees and
expenses you may pay if you buy, hold and sell shares of the fund. You may pay other fees, such as brokerage commissions and other fees
to financial intermediaries, which are not reflected in the tables and examples below. &lt;span id="xdx_90A_err--ExpenseBreakpointDiscounts_dU_c20220527__20220527__dei--LegalEntityAxis__custom--S000006568Member_z66CkMrngcy4"&gt;You may qualify for sales charge discounts if you
and your family invest, or agree to invest in the future, at least &lt;span id="xdx_907_err--ExpenseBreakpointMinimumInvestmentRequiredAmount_dU_c20220527__20220527__dei--LegalEntityAxis__custom--S000006568Member_zXKZXhKBwHYc"&gt;$50,000&lt;/span&gt; in class A shares of Putnam funds.&lt;/span&gt; More information about these
and other discounts is available from your financial professional and in &lt;i&gt;How do I buy fund shares?&lt;/i&gt; beginning on page &lt;/span&gt;15
&lt;span style="font-size: 11pt"&gt;of the fund&#x2019;s prospectus, in the Appendix to the fund&#x2019;s prospectus, and in How to buy shares
beginning on page II-1 of the fund&#x2019;s statement of additional information (SAI).&lt;/span&gt;&lt;/p&gt;

&lt;p style="font: 12pt Times New Roman, Times, Serif; margin: 0"&gt;&lt;b&gt;&#160;&lt;/b&gt;&lt;/p&gt;

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    <rr:ExpenseBreakpointDiscounts contextRef="AsOf2022-05-27_custom_S000006568Member">You may qualify for sales charge discounts if you
and your family invest, or agree to invest in the future, at least $50,000 in class A shares of Putnam funds.</rr:ExpenseBreakpointDiscounts>
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      contextRef="AsOf2022-05-27_custom_S000006568Member"
      decimals="0"
      unitRef="USD">50000</rr:ExpenseBreakpointMinimumInvestmentRequiredAmount>
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      contextRef="AsOf2022-05-27_custom_S000006568Member_custom_C000017918Member"
      decimals="INF"
      unitRef="Ratio">0.0400</rr:MaximumSalesChargeImposedOnPurchasesOverOfferingPrice>
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      id="Fact000020"
      unitRef="Ratio">0.0100</rr:MaximumDeferredSalesChargeOverOther>
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      decimals="INF"
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      contextRef="AsOf2022-05-27_custom_S000006568Member_custom_C000017917Member"
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    <rr:MaximumDeferredSalesChargeOverOther
      contextRef="AsOf2022-05-27_custom_S000006568Member_custom_C000202806Member"
      decimals="INF"
      unitRef="Ratio">0</rr:MaximumDeferredSalesChargeOverOther>
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      contextRef="AsOf2022-05-27_custom_S000006568Member_custom_C000060417Member"
      decimals="INF"
      unitRef="Ratio">0</rr:MaximumSalesChargeImposedOnPurchasesOverOfferingPrice>
    <rr:MaximumDeferredSalesChargeOverOther
      contextRef="AsOf2022-05-27_custom_S000006568Member_custom_C000060417Member"
      decimals="INF"
      unitRef="Ratio">0</rr:MaximumDeferredSalesChargeOverOther>
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          xlink:href="#Fact000020"
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        <link:footnote id="Footnote000029" xlink:label="Footnote000029" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US">
Applies only to certain redemptions of shares bought with no initial sales
charge.</link:footnote>
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        <link:footnote id="Footnote000030" xlink:label="Footnote000030" xlink:role="http://www.xbrl.org/2003/role/footnote" xlink:type="resource" xml:lang="en-US">
This charge is phased out over six years.</link:footnote>
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This charge is eliminated after one year.</link:footnote>
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