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            <startDate>2026-09-16</startDate>
            <endDate>2026-09-16</endDate>
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        <measure>iso4217:USD</measure>
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    <unit id="Shares">
        <measure>shares</measure>
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    <ffd:FormTp contextRef="rc" id="ixv-365">S-3</ffd:FormTp>
    <ffd:SubmissnTp contextRef="rc" id="ixv-366">424B2</ffd:SubmissnTp>
    <ffd:FeeExhibitTp contextRef="rc" id="ixv-367">EX-FILING FEES</ffd:FeeExhibitTp>
    <ffd:RegnFileNb contextRef="rc" id="ixv-368">333-296741</ffd:RegnFileNb>
    <dei:EntityCentralIndexKey contextRef="rc" id="ixv-369">0001734342</dei:EntityCentralIndexKey>
    <dei:EntityRegistrantName contextRef="rc" id="ixv-370">Amerant Bancorp Inc.</dei:EntityRegistrantName>
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      decimals="2"
      id="ixv-425"
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      contextRef="offrl_1"
      decimals="2"
      id="ixv-426"
      unitRef="USD">6869.23</ffd:FeeAmt>
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    <ffd:OfferingNote contextRef="offrl_1" id="ixv-432">The registration fee for the securities was previously paid in connection with the Registrant's Registration Statement on Form S-3ASR (File No. 333-296741), initially filed with the Securities and Exchange Commission on June 12, 2026, in accordance with Rule 457(o) under the Securities Act of 1933, as amended (the "Securities Act"). This "Calculation of Filing Fee Tables" shall be deemed to update the "Calculation of Filing Fee Tables" in the Registration Statement.</ffd:OfferingNote>
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    <ffd:OffsetPrrFilerNm contextRef="ofst_1" id="ixv-434">Amerant Bancorp, Inc.</ffd:OffsetPrrFilerNm>
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    <ffd:OffsetPrrFilerNm contextRef="ofst_2" id="ixv-443">Amerant Bancorp, Inc.</ffd:OffsetPrrFilerNm>
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    <ffd:OffsetPrrFileNb contextRef="ofst_2" id="ixv-445">333-238958</ffd:OffsetPrrFileNb>
    <ffd:OffsetSrcFilgDt contextRef="ofst_2" id="ixv-446">2020-06-05</ffd:OffsetSrcFilgDt>
    <ffd:OffsetPrrFeeAmt contextRef="ofst_2" decimals="2" id="ixv-447" unitRef="USD">12980.00</ffd:OffsetPrrFeeAmt>
    <ffd:TermntnCmpltnWdrwl contextRef="ofst_1" id="ixv-448">The Registrant previously filed a Registration Statement on Form S-3 (File No. 333-272886) on June 23, 2023, as amended (the "Prior Registration Statement"). In connection with the Prior Registration Statement, securities were registered for a maximum aggregate offering price of $300,000,000. Pursuant to Rule 415(a)(6) under the Securities Act, the offering of unsold securities under the Prior Registration Statement was deemed terminated upon the filing of the Registrant's Registration Statement on Form S-3ASR (File No. 333-296741) (the "Current Registration Statement"), initially filed on June 12, 2026. The Prior Registration Statement carried forward $135,000,010 of unsold securities and associated filing fees previously paid. The fee offset of $6,869.23 claimed herein was originally paid in connection with registration fees under the Registrant's earlier Registration Statement on Form S-3 (File No. 333-238958), filed on June 5, 2020, pursuant to which $12,980.00 in filing fees were paid. In accordance with Rule 457(p) under the Securities Act, $6,869.23 of such previously paid and unused filing fees is being used to offset the registration fee payable in connection with the offering of $49,741,000.00 in aggregate maximum offering price of the 7.00% Senior Notes due 2031 registered pursuant to the Current Registration Statement. Accordingly, no additional registration fee is due at this time.</ffd:TermntnCmpltnWdrwl>
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