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        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0000017313</identifier>
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        <period>
            <startDate>2026-09-11</startDate>
            <endDate>2026-09-11</endDate>
        </period>
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                <xbrldi:typedMember dimension="ffd:OfferingAxis">
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        <period>
            <startDate>2026-09-11</startDate>
            <endDate>2026-09-11</endDate>
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    <unit id="shares">
        <measure>shares</measure>
    </unit>
    <unit id="number">
        <measure>pure</measure>
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    <unit id="usd">
        <measure>iso4217:USD</measure>
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    <dei:EntityCentralIndexKey contextRef="c-41" id="f-120">0000017313</dei:EntityCentralIndexKey>
    <ffd:RegnFileNb contextRef="c-41" id="f-121">333-282873</ffd:RegnFileNb>
    <ffd:FormTp contextRef="c-41" id="f-122">N-2</ffd:FormTp>
    <ffd:SubmissnTp contextRef="c-41" id="f-123">424B2</ffd:SubmissnTp>
    <ffd:FeeExhibitTp contextRef="c-41" id="f-124">EX-FILING FEES</ffd:FeeExhibitTp>
    <ffd:OffsetTableNa contextRef="c-41" id="f-125">N/A</ffd:OffsetTableNa>
    <ffd:CombinedProspectusTableNa contextRef="c-41" id="f-126">N/A</ffd:CombinedProspectusTableNa>
    <dei:EntityRegistrantName contextRef="c-41" id="f-105">Capital Southwest Corporation</dei:EntityRegistrantName>
    <ffd:PrevslyPdFlg contextRef="c-42" id="f-106">false</ffd:PrevslyPdFlg>
    <ffd:OfferingSctyTp contextRef="c-42" id="f-107">Debt</ffd:OfferingSctyTp>
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    <ffd:OfferingNote contextRef="c-42" id="f-119">The registration fee is calculated in accordance with Rule 457(o) under the Securities Act of 1933, as amended (the &#x201c;Securities Act&#x201d;), based on the proposed maximum aggregate offering price, and Rule 456(b) and 457(r) under the Securities Act. In accordance with Rules 456(b) and 457(r) under the Securities Act, Capital Southwest Corporation (the &#x201c;Registrant&#x201d;) initially deferred payment of all of the registration fees relating to the Registrant&#x2019;s Registration Statement on Form N-2 (File No.&#160;333-282873), which was filed with the Securities and Exchange Commission (the &#x201c;SEC&#x201d;) on October 29, 2024 and automatically became effective upon filing with the SEC (the &#x201c;Registration Statement&#x201d;).&#160;This&#160;&#x201c;Calculation of Filing Fee Table&#x201d; shall be deemed to update the &#x201c;Calculation of Filing Fee Table&#x201d; in the Registration&#160;Statement.</ffd:OfferingNote>
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