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        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0001211583</identifier>
        </entity>
        <period>
            <startDate>2026-06-11</startDate>
            <endDate>2026-06-11</endDate>
        </period>
    </context>
    <context id="offrl_1">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0001211583</identifier>
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                <xbrldi:typedMember dimension="ffd:OfferingAxis">
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        <period>
            <startDate>2026-06-11</startDate>
            <endDate>2026-06-11</endDate>
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    <unit id="USD">
        <measure>iso4217:USD</measure>
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    <unit id="pure">
        <measure>pure</measure>
    </unit>
    <unit id="Shares">
        <measure>shares</measure>
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    <ffd:FormTp contextRef="rc" id="ixv-168">S-8</ffd:FormTp>
    <ffd:SubmissnTp contextRef="rc" id="ixv-169">S-8</ffd:SubmissnTp>
    <ffd:FeeExhibitTp contextRef="rc" id="ixv-170">EX-FILING FEES</ffd:FeeExhibitTp>
    <dei:EntityCentralIndexKey contextRef="rc" id="ixv-171">0001211583</dei:EntityCentralIndexKey>
    <dei:EntityRegistrantName contextRef="rc" id="ixv-172">FENNEC PHARMACEUTICALS INC.</dei:EntityRegistrantName>
    <ffd:OfferingTableNa contextRef="rc" id="hiddenrcOfferingTableNa" xsi:nil="true"/>
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    <ffd:FormTp contextRef="rc" id="ixv-200">S-8</ffd:FormTp>
    <dei:EntityRegistrantName contextRef="rc" id="ixv-201">FENNEC PHARMACEUTICALS INC.</dei:EntityRegistrantName>
    <ffd:OfferingSctyTp contextRef="offrl_1" id="ixv-202">Equity</ffd:OfferingSctyTp>
    <ffd:OfferingSctyTitl contextRef="offrl_1" id="ixv-203">Common shares, no par value per share </ffd:OfferingSctyTitl>
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    <ffd:AmtSctiesRegd
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      contextRef="offrl_1"
      decimals="2"
      id="ixv-206"
      unitRef="USD">8.86</ffd:MaxOfferingPricPerScty>
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      contextRef="offrl_1"
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      contextRef="offrl_1"
      decimals="7"
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      contextRef="offrl_1"
      decimals="2"
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      unitRef="USD">1835.35</ffd:FeeAmt>
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    <ffd:TtlFeeAmt contextRef="rc" decimals="2" id="ixv-211" unitRef="USD">1835.35</ffd:TtlFeeAmt>
    <ffd:TtlOffsetAmt contextRef="rc" decimals="2" id="ixv-212" unitRef="USD">0.00</ffd:TtlOffsetAmt>
    <ffd:NetFeeAmt contextRef="rc" decimals="2" id="ixv-213" unitRef="USD">1835.35</ffd:NetFeeAmt>
    <ffd:OfferingNote contextRef="offrl_1" id="ixv-214">Consists of common shares, no par value per share ("Common Shares"), of Fennec Pharmaceuticals Inc. (the "Registrant") that are issuable under the Registrant's 2020 Equity Incentive Plan. Pursuant to Rule 416(a) promulgated under the Securities Act of 1933, as amended (the "Securities Act"), this Registration Statement shall also cover any additional shares of Registrant's Common Shares that become issuable under the 2020 Equity Incentive Plan by reason of any stock dividend, stock split, recapitalization, or other similar transaction.

Estimated in accordance with Rules 457(c) and (h) of the Securities Act solely for the purpose of calculating the registration fee on the basis of $8.86 per share, which is the average of the high and low prices of the Common Shares as reported on The Nasdaq Capital Market on June 5, 2026. </ffd:OfferingNote>
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