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        <measure>iso4217:USD</measure>
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        <measure>pure</measure>
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        <measure>shares</measure>
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    <ffd:FormTp contextRef="rc" id="ixv-383">N-2</ffd:FormTp>
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    <ffd:FeeExhibitTp contextRef="rc" id="ixv-385">EX-FILING FEES</ffd:FeeExhibitTp>
    <ffd:RegnFileNb contextRef="rc" id="ixv-386">333-293856</ffd:RegnFileNb>
    <dei:EntityCentralIndexKey contextRef="rc" id="ixv-387">0001513363</dei:EntityCentralIndexKey>
    <dei:EntityRegistrantName contextRef="rc" id="ixv-388">FIDUS INVESTMENT Corp</dei:EntityRegistrantName>
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    <ffd:FormTp contextRef="rc" id="ixv-436">N-2</ffd:FormTp>
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    <ffd:MaxAggtOfferingPric
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      id="ixv-442"
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      contextRef="offrl_1"
      decimals="7"
      id="ixv-443"
      unitRef="pure">0.0001381</ffd:FeeRate>
    <ffd:FeeAmt
      contextRef="offrl_1"
      decimals="2"
      id="ixv-444"
      unitRef="USD">13810.00</ffd:FeeAmt>
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    <ffd:TtlFeeAmt contextRef="rc" decimals="2" id="ixv-446" unitRef="USD">13810.00</ffd:TtlFeeAmt>
    <ffd:TtlPrevslyPdAmt contextRef="rc" decimals="2" id="ixv-447" unitRef="USD">0.00</ffd:TtlPrevslyPdAmt>
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    <ffd:OfferingNote contextRef="offrl_1" id="ixv-450">Unsold Securities includes $100,000,000 of Unsold Securities of the Registrant previously registered on the Registration Statement in Table 2. Pursuant to Rule 457(p) under the Securities Act, the $13,810 fee paid to register the Unsold Securities is offset against the filing fees to be paid pursuant to Table 1.</ffd:OfferingNote>
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    <ffd:OffsetClmInitlFilgDt contextRef="ofst_1" id="ixv-455">2024-02-29</ffd:OffsetClmInitlFilgDt>
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    <ffd:OffsetPrrSctyTitl contextRef="ofst_1" id="ixv-458">Common Stock, $0.01 par value</ffd:OffsetPrrSctyTitl>
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      decimals="0"
      id="ixv-459"
      unitRef="Shares">0</ffd:OffsetPrrNbOfUnsoldScties>
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    <ffd:OffsetPrrFilerNm contextRef="ofst_2" id="ixv-462">Fidus Investment Corporation</ffd:OffsetPrrFilerNm>
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    <ffd:TermntnCmpltnWdrwl contextRef="ofst_1" id="ixv-467">The registrant has terminated any offering that included the unsold securities under the Registration Statement on Form N-2 (File No. 333-277540), which was initially filed on February 29, 2024.</ffd:TermntnCmpltnWdrwl>
    <ffd:OffsetNote contextRef="ofst_1" id="ixv-468">Certain of the securities being offered under this prospectus supplement represent unsold securities previously registered on the prospectus supplement filed pursuant to Rule 424(b)(2) on May 8, 2024 (the "Prior Prospectus Supplement"), which had a balance of $34,774,520 of unsold securities in respect of which the registrant paid a registration fee of $4,802.36, and the Registration Statement on Form N-2 (File No. 333-277540), which was initially filed with the Securities and Exchange Commission on February 29, 2024 (the "Prior Registration Statement), which had $100,000,000 of unsold securities in respect of which the registrant paid a registration fee of $13,810.00. Accordingly, as of the date hereof, the maximum aggregate offering amount of the unsold securities registered pursuant to the Prior Prospectus Supplement and the Prior Registration Statement (the "Unsold Securities") is $134,774,520. In connection with the registration of the Unsold Securities, the registrant paid a registration fee of $18,612.36, which will be applied to the Unsold Securities that are being offered pursuant to this prospectus supplement.</ffd:OffsetNote>
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    <ffd:FnlPrspctsFlg contextRef="rc" id="ixv-470">true</ffd:FnlPrspctsFlg>
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