<?xml version='1.0' encoding='utf-8'?>
<FilingSummary>
  <Version>3.25.2</Version>
  <ProcessingTime/>
  <ReportFormat>html</ReportFormat>
  <ContextCount>287</ContextCount>
  <ElementCount>367</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>true</FootnotesReported>
  <SegmentCount>103</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>10</UnitCount>
  <MyReports>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>000 - Document - Document And Entity Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/DocumentAndEntityInformation</Role>
      <ShortName>Document And Entity Information</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>1</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>001 - Statement - CONDENSED CONSOLIDATED INTERIM STATEMENTS OF FINANCIAL POSITION</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/ConsolidatedBalanceSheet</Role>
      <ShortName>CONDENSED CONSOLIDATED INTERIM STATEMENTS OF FINANCIAL POSITION</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>2</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>002 - Statement - CONDENSED CONSOLIDATED INTERIM STATEMENTS OF LOSS AND COMPREHENSIVE LOSS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/ConsolidatedIncomeStatement</Role>
      <ShortName>CONDENSED CONSOLIDATED INTERIM STATEMENTS OF LOSS AND COMPREHENSIVE LOSS</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>3</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>003 - Statement - CONDENSED CONSOLIDATED INTERIM STATEMENTS OF CHANGES IN SHAREHOLDERS??? EQUITY</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/ShareholdersEquityType2or3</Role>
      <ShortName>CONDENSED CONSOLIDATED INTERIM STATEMENTS OF CHANGES IN SHAREHOLDERS??? EQUITY</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>4</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R5.htm</HtmlFileName>
      <LongName>004 - Statement - CONDENSED CONSOLIDATED INTERIM STATEMENTS OF CHANGES IN CASH FLOWS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/ConsolidatedCashFlow</Role>
      <ShortName>CONDENSED CONSOLIDATED INTERIM STATEMENTS OF CHANGES IN CASH FLOWS</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>5</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R6.htm</HtmlFileName>
      <LongName>005 - Disclosure - Nature of business</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/Natureofbusiness</Role>
      <ShortName>Nature of business</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>6</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>006 - Disclosure - Basis of presentation</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/Basisofpresentation</Role>
      <ShortName>Basis of presentation</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>7</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>007 - Disclosure - New standards, amendments and interpretations adopted by the Company</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/NewstandardsamendmentsandinterpretationsadoptedbytheCompany</Role>
      <ShortName>New standards, amendments and interpretations adopted by the Company</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>8</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.htm</HtmlFileName>
      <LongName>008 - Disclosure - Other receivables</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/Otherreceivables</Role>
      <ShortName>Other receivables</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>9</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R10.htm</HtmlFileName>
      <LongName>009 - Disclosure - Prepaid expenses and deposits</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/Prepaidexpensesanddeposits</Role>
      <ShortName>Prepaid expenses and deposits</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>10</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>010 - Disclosure - Finance receivables</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/Financereceivables</Role>
      <ShortName>Finance receivables</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>11</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>011 - Disclosure - Investments</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/Investments</Role>
      <ShortName>Investments</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>12</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>012 - Disclosure - Inventory</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/Inventory</Role>
      <ShortName>Inventory</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>13</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>013 - Disclosure - Digital assets</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/Digitalassets</Role>
      <ShortName>Digital assets</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>14</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R15.htm</HtmlFileName>
      <LongName>014 - Disclosure - Intangible assets</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/Intangibleassets</Role>
      <ShortName>Intangible assets</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>15</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>015 - Disclosure - Trade and other payables</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/Tradeandotherpayables</Role>
      <ShortName>Trade and other payables</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>16</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>016 - Disclosure - Warrants Liability</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/WarrantsLiability</Role>
      <ShortName>Warrants Liability</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>17</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R18.htm</HtmlFileName>
      <LongName>017 - Disclosure - Notes payable</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.quantumbiopharma.com/role/Notespayable</Role>
      <ShortName>Notes payable</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>18</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R19.htm</HtmlFileName>
      <LongName>018 - Disclosure - Convertible debentures</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/Convertibledebentures</Role>
      <ShortName>Convertible debentures</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>19</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R20.htm</HtmlFileName>
      <LongName>019 - Disclosure - Share capital</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/Sharecapital</Role>
      <ShortName>Share capital</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>20</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R21.htm</HtmlFileName>
      <LongName>020 - Disclosure - Share-based compensation</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/Sharebasedcompensation</Role>
      <ShortName>Share-based compensation</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>21</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R22.htm</HtmlFileName>
      <LongName>021 - Disclosure - Non-controlling interests</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/Noncontrollinginterests</Role>
      <ShortName>Non-controlling interests</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>22</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R23.htm</HtmlFileName>
      <LongName>022 - Disclosure - Loss per share</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/Losspershare</Role>
      <ShortName>Loss per share</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>23</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R24.htm</HtmlFileName>
      <LongName>023 - Disclosure - General and administrative</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/Generalandadministrative</Role>
      <ShortName>General and administrative</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>24</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>024 - Disclosure - Segment information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/Segmentinformation</Role>
      <ShortName>Segment information</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>25</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>025 - Disclosure - Commitments and contingencies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/Commitmentsandcontingencies</Role>
      <ShortName>Commitments and contingencies</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>26</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R27.htm</HtmlFileName>
      <LongName>026 - Disclosure - Related party transactions</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/Relatedpartytransactions</Role>
      <ShortName>Related party transactions</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>27</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R28.htm</HtmlFileName>
      <LongName>027 - Disclosure - Capital Management</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/CapitalManagement</Role>
      <ShortName>Capital Management</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>28</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R29.htm</HtmlFileName>
      <LongName>028 - Disclosure - Financial Instruments and Risk Management</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/FinancialInstrumentsandRiskManagement</Role>
      <ShortName>Financial Instruments and Risk Management</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>29</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R30.htm</HtmlFileName>
      <LongName>029 - Disclosure - Subsequent Events</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/SubsequentEvents</Role>
      <ShortName>Subsequent Events</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>30</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R31.htm</HtmlFileName>
      <LongName>996000 - Disclosure - Accounting Policies, by Policy (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/AccountingPoliciesByPolicy</Role>
      <ShortName>Accounting Policies, by Policy (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <Position>31</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R32.htm</HtmlFileName>
      <LongName>996001 - Disclosure - Nature of business (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/NatureofbusinessTables</Role>
      <ShortName>Nature of business (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.quantumbiopharma.com/role/Natureofbusiness</ParentRole>
      <Position>32</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R33.htm</HtmlFileName>
      <LongName>996002 - Disclosure - Other receivables (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/OtherreceivablesTables</Role>
      <ShortName>Other receivables (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.quantumbiopharma.com/role/Otherreceivables</ParentRole>
      <Position>33</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R34.htm</HtmlFileName>
      <LongName>996003 - Disclosure - Prepaid expenses and deposits (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/PrepaidexpensesanddepositsTables</Role>
      <ShortName>Prepaid expenses and deposits (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.quantumbiopharma.com/role/Prepaidexpensesanddeposits</ParentRole>
      <Position>34</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R35.htm</HtmlFileName>
      <LongName>996004 - Disclosure - Finance receivables (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/FinancereceivablesTables</Role>
      <ShortName>Finance receivables (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.quantumbiopharma.com/role/Financereceivables</ParentRole>
      <Position>35</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R36.htm</HtmlFileName>
      <LongName>996005 - Disclosure - Investments (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/InvestmentsTables</Role>
      <ShortName>Investments (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.quantumbiopharma.com/role/Investments</ParentRole>
      <Position>36</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R37.htm</HtmlFileName>
      <LongName>996006 - Disclosure - Inventory (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/InventoryTables</Role>
      <ShortName>Inventory (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.quantumbiopharma.com/role/Inventory</ParentRole>
      <Position>37</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R38.htm</HtmlFileName>
      <LongName>996007 - Disclosure - Digital assets (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/DigitalassetsTables</Role>
      <ShortName>Digital assets (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.quantumbiopharma.com/role/Digitalassets</ParentRole>
      <Position>38</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R39.htm</HtmlFileName>
      <LongName>996008 - Disclosure - Intangible assets (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/IntangibleassetsTables</Role>
      <ShortName>Intangible assets (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.quantumbiopharma.com/role/Intangibleassets</ParentRole>
      <Position>39</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R40.htm</HtmlFileName>
      <LongName>996009 - Disclosure - Trade and other payables (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/TradeandotherpayablesTables</Role>
      <ShortName>Trade and other payables (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.quantumbiopharma.com/role/Tradeandotherpayables</ParentRole>
      <Position>40</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R41.htm</HtmlFileName>
      <LongName>996010 - Disclosure - Warrants Liability (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/WarrantsLiabilityTables</Role>
      <ShortName>Warrants Liability (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.quantumbiopharma.com/role/WarrantsLiability</ParentRole>
      <Position>41</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R42.htm</HtmlFileName>
      <LongName>996011 - Disclosure - Convertible debentures (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/ConvertibledebenturesTables</Role>
      <ShortName>Convertible debentures (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.quantumbiopharma.com/role/Convertibledebentures</ParentRole>
      <Position>42</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R43.htm</HtmlFileName>
      <LongName>996012 - Disclosure - Share capital (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/SharecapitalTables</Role>
      <ShortName>Share capital (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.quantumbiopharma.com/role/Sharecapital</ParentRole>
      <Position>43</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R44.htm</HtmlFileName>
      <LongName>996013 - Disclosure - Share-based compensation (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/SharebasedcompensationTables</Role>
      <ShortName>Share-based compensation (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.quantumbiopharma.com/role/Sharebasedcompensation</ParentRole>
      <Position>44</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R45.htm</HtmlFileName>
      <LongName>996014 - Disclosure - Non-controlling interests (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/NoncontrollinginterestsTables</Role>
      <ShortName>Non-controlling interests (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.quantumbiopharma.com/role/Noncontrollinginterests</ParentRole>
      <Position>45</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R46.htm</HtmlFileName>
      <LongName>996015 - Disclosure - General and administrative (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/GeneralandadministrativeTables</Role>
      <ShortName>General and administrative (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.quantumbiopharma.com/role/Generalandadministrative</ParentRole>
      <Position>46</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R47.htm</HtmlFileName>
      <LongName>996016 - Disclosure - Segment information (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/SegmentinformationTables</Role>
      <ShortName>Segment information (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.quantumbiopharma.com/role/Segmentinformation</ParentRole>
      <Position>47</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R48.htm</HtmlFileName>
      <LongName>996017 - Disclosure - Related party transactions (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/RelatedpartytransactionsTables</Role>
      <ShortName>Related party transactions (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.quantumbiopharma.com/role/Relatedpartytransactions</ParentRole>
      <Position>48</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R49.htm</HtmlFileName>
      <LongName>996018 - Disclosure - Nature of business (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/NatureofbusinessDetails</Role>
      <ShortName>Nature of business (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.quantumbiopharma.com/role/NatureofbusinessTables</ParentRole>
      <Position>49</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R50.htm</HtmlFileName>
      <LongName>996019 - Disclosure - Nature of business - Schedule of subsidiaries percentage (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/ScheduleofsubsidiariespercentageTable</Role>
      <ShortName>Nature of business - Schedule of subsidiaries percentage (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>50</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R51.htm</HtmlFileName>
      <LongName>996020 - Disclosure - Other receivables - Schedule of other receivables (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/ScheduleofotherreceivablesTable</Role>
      <ShortName>Other receivables - Schedule of other receivables (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>51</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R52.htm</HtmlFileName>
      <LongName>996021 - Disclosure - Prepaid expenses and deposits - Schedule of Prepaid expenses and deposits (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/ScheduleofPrepaidexpensesanddepositsTable</Role>
      <ShortName>Prepaid expenses and deposits - Schedule of Prepaid expenses and deposits (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>52</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R53.htm</HtmlFileName>
      <LongName>996022 - Disclosure - Finance receivables (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/FinancereceivablesDetails</Role>
      <ShortName>Finance receivables (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.quantumbiopharma.com/role/FinancereceivablesTables</ParentRole>
      <Position>53</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R54.htm</HtmlFileName>
      <LongName>996023 - Disclosure - Finance receivables - Schedule of finance receivables measured at amortized cost, net of allowance (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/ScheduleoffinancereceivablesmeasuredatamortizedcostnetofallowanceTable</Role>
      <ShortName>Finance receivables - Schedule of finance receivables measured at amortized cost, net of allowance (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>54</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R55.htm</HtmlFileName>
      <LongName>996024 - Disclosure - Finance receivables - Schedule of finance receivables (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/ScheduleoffinancereceivablesTable</Role>
      <ShortName>Finance receivables - Schedule of finance receivables (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>55</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R56.htm</HtmlFileName>
      <LongName>996025 - Disclosure - Investments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/InvestmentsDetails</Role>
      <ShortName>Investments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.quantumbiopharma.com/role/InvestmentsTables</ParentRole>
      <Position>56</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R57.htm</HtmlFileName>
      <LongName>996026 - Disclosure - Investments - Disclosure of investments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/DisclosureofinvestmentsTable</Role>
      <ShortName>Investments - Disclosure of investments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>57</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R58.htm</HtmlFileName>
      <LongName>996027 - Disclosure - Inventory - Schedule of Inventory (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/ScheduleofInventoryTable</Role>
      <ShortName>Inventory - Schedule of Inventory (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>58</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R59.htm</HtmlFileName>
      <LongName>996028 - Disclosure - Digital assets (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/DigitalassetsDetails</Role>
      <ShortName>Digital assets (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.quantumbiopharma.com/role/DigitalassetsTables</ParentRole>
      <Position>59</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R60.htm</HtmlFileName>
      <LongName>996029 - Disclosure - Digital assets - Schedule of fair value and cost of digital assets (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/ScheduleoffairvalueandcostofdigitalassetsTable</Role>
      <ShortName>Digital assets - Schedule of fair value and cost of digital assets (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>60</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R61.htm</HtmlFileName>
      <LongName>996030 - Disclosure - Digital assets - Schedule of fair value hierarchy (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/ScheduleoffairvaluehierarchyTable</Role>
      <ShortName>Digital assets - Schedule of fair value hierarchy (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>61</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R62.htm</HtmlFileName>
      <LongName>996031 - Disclosure - Intangible assets - Schedule of intangible assets (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/ScheduleofintangibleassetsTable</Role>
      <ShortName>Intangible assets - Schedule of intangible assets (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>62</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R63.htm</HtmlFileName>
      <LongName>996032 - Disclosure - Trade and other payables - Schedule of trade and other payables (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/ScheduleoftradeandotherpayablesTable</Role>
      <ShortName>Trade and other payables - Schedule of trade and other payables (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>63</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R64.htm</HtmlFileName>
      <LongName>996033 - Disclosure - Trade and other payables - Schedule of accrued liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/ScheduleofaccruedliabilitiesTable</Role>
      <ShortName>Trade and other payables - Schedule of accrued liabilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>64</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R65.htm</HtmlFileName>
      <LongName>996034 - Disclosure - Warrants Liability (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/WarrantsLiabilityDetails</Role>
      <ShortName>Warrants Liability (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.quantumbiopharma.com/role/WarrantsLiabilityTables</ParentRole>
      <Position>65</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R66.htm</HtmlFileName>
      <LongName>996035 - Disclosure - Warrants Liability - Schedule of fair value determined using black-scholes option (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/ScheduleoffairvaluedeterminedusingblackscholesoptionTable</Role>
      <ShortName>Warrants Liability - Schedule of fair value determined using black-scholes option (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>66</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R67.htm</HtmlFileName>
      <LongName>996036 - Disclosure - Notes payable (Details)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.quantumbiopharma.com/role/NotespayableDetails</Role>
      <ShortName>Notes payable (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.quantumbiopharma.com/role/Notespayable</ParentRole>
      <Position>67</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R68.htm</HtmlFileName>
      <LongName>996037 - Disclosure - Convertible debentures (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/ConvertibledebenturesDetails</Role>
      <ShortName>Convertible debentures (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.quantumbiopharma.com/role/ConvertibledebenturesTables</ParentRole>
      <Position>68</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R69.htm</HtmlFileName>
      <LongName>996038 - Disclosure - Convertible debentures - Schedule of gain on change in fair value (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/ScheduleofgainonchangeinfairvalueTable</Role>
      <ShortName>Convertible debentures - Schedule of gain on change in fair value (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>69</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R70.htm</HtmlFileName>
      <LongName>996039 - Disclosure - Convertible debentures - Schedule of convertible debentures (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/ScheduleofconvertibledebenturesTable</Role>
      <ShortName>Convertible debentures - Schedule of convertible debentures (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>70</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R71.htm</HtmlFileName>
      <LongName>996040 - Disclosure - Share capital (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/SharecapitalDetails</Role>
      <ShortName>Share capital (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.quantumbiopharma.com/role/SharecapitalTables</ParentRole>
      <Position>71</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R72.htm</HtmlFileName>
      <LongName>996041 - Disclosure - Share capital - Schedule of changes in share capital (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/ScheduleofchangesinsharecapitalTable</Role>
      <ShortName>Share capital - Schedule of changes in share capital (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>72</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R73.htm</HtmlFileName>
      <LongName>996042 - Disclosure - Share capital - Schedule of changes in warrants outstanding and weighted average exercise price (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/ScheduleofchangesinwarrantsoutstandingandweightedaverageexercisepriceTable</Role>
      <ShortName>Share capital - Schedule of changes in warrants outstanding and weighted average exercise price (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>73</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R74.htm</HtmlFileName>
      <LongName>996043 - Disclosure - Share capital - Schedule of number of warrants outstanding and exercise price (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/ScheduleofnumberofwarrantsoutstandingandexercisepriceTable</Role>
      <ShortName>Share capital - Schedule of number of warrants outstanding and exercise price (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>74</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R75.htm</HtmlFileName>
      <LongName>996044 - Disclosure - Share-based compensation (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/SharebasedcompensationDetails</Role>
      <ShortName>Share-based compensation (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.quantumbiopharma.com/role/SharebasedcompensationTables</ParentRole>
      <Position>75</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R76.htm</HtmlFileName>
      <LongName>996045 - Disclosure - Share-based compensation - Schedule of number of share options outstanding (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/ScheduleofnumberofshareoptionsoutstandingTable</Role>
      <ShortName>Share-based compensation - Schedule of number of share options outstanding (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>76</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R77.htm</HtmlFileName>
      <LongName>996046 - Disclosure - Share-based compensation - Schedule of fair values of options granted using the Black-Scholes option pricing model (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/ScheduleoffairvaluesofoptionsgrantedusingtheBlackScholesoptionpricingmodelTable</Role>
      <ShortName>Share-based compensation - Schedule of fair values of options granted using the Black-Scholes option pricing model (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>77</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R78.htm</HtmlFileName>
      <LongName>996047 - Disclosure - Share-based compensation - Schedule of company???s share options outstanding (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/ScheduleofcompanysshareoptionsoutstandingTable</Role>
      <ShortName>Share-based compensation - Schedule of company???s share options outstanding (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>78</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R79.htm</HtmlFileName>
      <LongName>996048 - Disclosure - Share-based compensation - Schedule of fair values of PSUs granted using the Black-Scholes option pricing model (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/ScheduleoffairvaluesofPSUsgrantedusingtheBlackScholesoptionpricingmodelTable</Role>
      <ShortName>Share-based compensation - Schedule of fair values of PSUs granted using the Black-Scholes option pricing model (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>79</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R80.htm</HtmlFileName>
      <LongName>996049 - Disclosure - Share-based compensation - Schedule of share-based compensation (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/ScheduleofsharebasedcompensationTable</Role>
      <ShortName>Share-based compensation - Schedule of share-based compensation (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>80</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R81.htm</HtmlFileName>
      <LongName>996050 - Disclosure - Non-controlling interests (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/NoncontrollinginterestsDetails</Role>
      <ShortName>Non-controlling interests (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.quantumbiopharma.com/role/NoncontrollinginterestsTables</ParentRole>
      <Position>81</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R82.htm</HtmlFileName>
      <LongName>996051 - Disclosure - Non-controlling interests - Schedule of reconciliation of non controlling interest (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/ScheduleofreconciliationofnoncontrollinginterestTable</Role>
      <ShortName>Non-controlling interests - Schedule of reconciliation of non controlling interest (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>82</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R83.htm</HtmlFileName>
      <LongName>996052 - Disclosure - Loss per share - Schedule of loss per share (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/ScheduleoflosspershareTable</Role>
      <ShortName>Loss per share - Schedule of loss per share (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>83</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R84.htm</HtmlFileName>
      <LongName>996053 - Disclosure - General and administrative - Schedule of general and administrative expense (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/ScheduleofgeneralandadministrativeexpenseTable</Role>
      <ShortName>General and administrative - Schedule of general and administrative expense (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>84</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R85.htm</HtmlFileName>
      <LongName>996054 - Disclosure - Segment information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/SegmentinformationDetails</Role>
      <ShortName>Segment information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.quantumbiopharma.com/role/SegmentinformationTables</ParentRole>
      <Position>85</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R86.htm</HtmlFileName>
      <LongName>996055 - Disclosure - Segment information - Schedule of asset and income by segment (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/ScheduleofassetandincomebysegmentTable</Role>
      <ShortName>Segment information - Schedule of asset and income by segment (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>86</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R87.htm</HtmlFileName>
      <LongName>996056 - Disclosure - Commitments and contingencies (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/CommitmentsandcontingenciesDetails</Role>
      <ShortName>Commitments and contingencies (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.quantumbiopharma.com/role/Commitmentsandcontingencies</ParentRole>
      <Position>87</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R88.htm</HtmlFileName>
      <LongName>996057 - Disclosure - Related party transactions (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/RelatedpartytransactionsDetails</Role>
      <ShortName>Related party transactions (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.quantumbiopharma.com/role/RelatedpartytransactionsTables</ParentRole>
      <Position>88</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R89.htm</HtmlFileName>
      <LongName>996058 - Disclosure - Related party transactions - Schedule of key management personnel compensation (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/ScheduleofkeymanagementpersonnelcompensationTable</Role>
      <ShortName>Related party transactions - Schedule of key management personnel compensation (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>89</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R90.htm</HtmlFileName>
      <LongName>996059 - Disclosure - Capital Management (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/CapitalManagementDetails</Role>
      <ShortName>Capital Management (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.quantumbiopharma.com/role/CapitalManagement</ParentRole>
      <Position>90</Position>
    </Report>
    <Report instance="qntm6ka1061325.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R91.htm</HtmlFileName>
      <LongName>996060 - Disclosure - Subsequent Events (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.quantumbiopharma.com/role/SubsequentEventsDetails</Role>
      <ShortName>Subsequent Events (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.quantumbiopharma.com/role/SubsequentEvents</ParentRole>
      <Position>91</Position>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <LongName>All Reports</LongName>
      <ReportType>Book</ReportType>
      <ShortName>All Reports</ShortName>
    </Report>
  </MyReports>
  <InputFiles>
    <File>qntm-20250331.xsd</File>
    <File>qntm-20250331_cal.xml</File>
    <File>qntm-20250331_def.xml</File>
    <File>qntm-20250331_lab.xml</File>
    <File>qntm-20250331_pre.xml</File>
    <File doctype="6-K/A" isDefinitelyFs="true" isIfrs="true" isUsgaap="true" original="qntm6ka1061325.htm">qntm6ka1061325.htm</File>
    <File doctype="6-K/A" isDefinitelyFs="true" isIfrs="true" isUsgaap="true" original="qntmex99-1.htm">qntmex99-1.htm</File>
  </InputFiles>
  <SupplementalFiles/>
  <BaseTaxonomies>
    <BaseTaxonomy items="16">http://xbrl.sec.gov/dei/2024</BaseTaxonomy>
    <BaseTaxonomy items="485">https://xbrl.ifrs.org/taxonomy/2024-03-27/ifrs-full</BaseTaxonomy>
  </BaseTaxonomies>
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
