<?xml version='1.0' encoding='utf-8'?>
<FilingSummary>
  <Version>3.25.4</Version>
  <ProcessingTime/>
  <ReportFormat>html</ReportFormat>
  <ContextCount>731</ContextCount>
  <ElementCount>566</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>false</FootnotesReported>
  <SegmentCount>181</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>17</UnitCount>
  <MyReports>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>0000001 - Document - Cover Page</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/CoverPage</Role>
      <ShortName>Cover Page</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>1</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>0000002 - Document - Audit information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/Auditinformation</Role>
      <ShortName>Audit information</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>2</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>9952151 - Statement - CONSOLIDATED STATEMENTS OF INCOME</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/CONSOLIDATEDSTATEMENTSOFINCOME</Role>
      <ShortName>CONSOLIDATED STATEMENTS OF INCOME</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>3</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>9952152 - Statement - CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/CONSOLIDATEDSTATEMENTSOFCOMPREHENSIVEINCOME</Role>
      <ShortName>CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>4</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R5.htm</HtmlFileName>
      <LongName>9952153 - Statement - CONSOLIDATED BALANCE SHEETS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/CONSOLIDATEDBALANCESHEETS</Role>
      <ShortName>CONSOLIDATED BALANCE SHEETS</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>5</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R6.htm</HtmlFileName>
      <LongName>9952154 - Statement - CONSOLIDATED BALANCE SHEETS (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/CONSOLIDATEDBALANCESHEETSParenthetical</Role>
      <ShortName>CONSOLIDATED BALANCE SHEETS (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>6</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>9952155 - Statement - CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/CONSOLIDATEDSTATEMENTSOFSTOCKHOLDERSEQUITY</Role>
      <ShortName>CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>7</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>9952156 - Statement - CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/CONSOLIDATEDSTATEMENTSOFSTOCKHOLDERSEQUITYParenthetical</Role>
      <ShortName>CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>8</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.htm</HtmlFileName>
      <LongName>9952157 - Statement - CONSOLIDATED STATEMENTS OF CASH FLOWS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/CONSOLIDATEDSTATEMENTSOFCASHFLOWS</Role>
      <ShortName>CONSOLIDATED STATEMENTS OF CASH FLOWS</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>9</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R10.htm</HtmlFileName>
      <LongName>9952158 - Disclosure - Summary of significant accounting policies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/Summaryofsignificantaccountingpolicies</Role>
      <ShortName>Summary of significant accounting policies</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>10</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>9952159 - Disclosure - Segment and other information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/Segmentandotherinformation</Role>
      <ShortName>Segment and other information</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>11</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>9952160 - Disclosure - Revenues</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/Revenues</Role>
      <ShortName>Revenues</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>12</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>9952161 - Disclosure - Acquisitions</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/Acquisitions</Role>
      <ShortName>Acquisitions</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>13</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>9952162 - Disclosure - Stock-based compensation</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/Stockbasedcompensation</Role>
      <ShortName>Stock-based compensation</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>14</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R15.htm</HtmlFileName>
      <LongName>9952163 - Disclosure - Defined contribution plan</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/Definedcontributionplan</Role>
      <ShortName>Defined contribution plan</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>15</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>9952164 - Disclosure - Income taxes</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/Incometaxes</Role>
      <ShortName>Income taxes</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>16</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>9952165 - Disclosure - Earnings per share</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/Earningspershare</Role>
      <ShortName>Earnings per share</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>17</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R18.htm</HtmlFileName>
      <LongName>9952166 - Disclosure - Collaborations</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/Collaborations</Role>
      <ShortName>Collaborations</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>18</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R19.htm</HtmlFileName>
      <LongName>9952167 - Disclosure - Investments</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/Investments</Role>
      <ShortName>Investments</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>19</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R20.htm</HtmlFileName>
      <LongName>9952168 - Disclosure - Inventories</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/Inventories</Role>
      <ShortName>Inventories</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>20</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R21.htm</HtmlFileName>
      <LongName>9952169 - Disclosure - Property, plant and equipment</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/Propertyplantandequipment</Role>
      <ShortName>Property, plant and equipment</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>21</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R22.htm</HtmlFileName>
      <LongName>9952170 - Disclosure - Goodwill and other intangible assets</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/Goodwillandotherintangibleassets</Role>
      <ShortName>Goodwill and other intangible assets</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>22</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R23.htm</HtmlFileName>
      <LongName>9952171 - Disclosure - Leases</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/Leases</Role>
      <ShortName>Leases</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>23</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R24.htm</HtmlFileName>
      <LongName>9952172 - Disclosure - Other current assets and accrued liabilities</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/Othercurrentassetsandaccruedliabilities</Role>
      <ShortName>Other current assets and accrued liabilities</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>24</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>9952173 - Disclosure - Financing arrangements</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/Financingarrangements</Role>
      <ShortName>Financing arrangements</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>25</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>9952174 - Disclosure - Stockholders' equity</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/Stockholdersequity</Role>
      <ShortName>Stockholders' equity</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>26</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R27.htm</HtmlFileName>
      <LongName>9952175 - Disclosure - Fair value measurement</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/Fairvaluemeasurement</Role>
      <ShortName>Fair value measurement</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>27</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R28.htm</HtmlFileName>
      <LongName>9952176 - Disclosure - Derivative instruments</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/Derivativeinstruments</Role>
      <ShortName>Derivative instruments</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>28</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R29.htm</HtmlFileName>
      <LongName>9952177 - Disclosure - Contingencies and commitments</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/Contingenciesandcommitments</Role>
      <ShortName>Contingencies and commitments</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>29</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R30.htm</HtmlFileName>
      <LongName>9952178 - Disclosure - SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/SCHEDULEIIVALUATIONANDQUALIFYINGACCOUNTS</Role>
      <ShortName>SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>30</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R31.htm</HtmlFileName>
      <LongName>995445 - Disclosure - Insider Trading Arrangements</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://xbrl.sec.gov/ecd/role/InsiderTradingArrangements</Role>
      <ShortName>Insider Trading Arrangements</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>31</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R32.htm</HtmlFileName>
      <LongName>995447 - Disclosure - Insider Trading Policies and Procedures</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://xbrl.sec.gov/ecd/role/InsiderTradingPoliciesProc</Role>
      <ShortName>Insider Trading Policies and Procedures</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>32</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R33.htm</HtmlFileName>
      <LongName>995550 - Disclosure - Cybersecurity Risk Management and Strategy Disclosure</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://xbrl.sec.gov/cyd/role/CybersecurityRiskManagementAndStrategyDisclosure</Role>
      <ShortName>Cybersecurity Risk Management and Strategy Disclosure</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>33</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R34.htm</HtmlFileName>
      <LongName>9955511 - Disclosure - Summary of significant accounting policies (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/SummaryofsignificantaccountingpoliciesPolicies</Role>
      <ShortName>Summary of significant accounting policies (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <Position>34</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R35.htm</HtmlFileName>
      <LongName>9955512 - Disclosure - Segment and other information (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/SegmentandotherinformationTables</Role>
      <ShortName>Segment and other information (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.amgen.com/role/Segmentandotherinformation</ParentRole>
      <Position>35</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R36.htm</HtmlFileName>
      <LongName>9955513 - Disclosure - Revenues (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/RevenuesTables</Role>
      <ShortName>Revenues (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.amgen.com/role/Revenues</ParentRole>
      <Position>36</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R37.htm</HtmlFileName>
      <LongName>9955514 - Disclosure - Acquisitions (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/AcquisitionsTables</Role>
      <ShortName>Acquisitions (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.amgen.com/role/Acquisitions</ParentRole>
      <Position>37</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R38.htm</HtmlFileName>
      <LongName>9955515 - Disclosure - Stock-based compensation (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/StockbasedcompensationTables</Role>
      <ShortName>Stock-based compensation (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.amgen.com/role/Stockbasedcompensation</ParentRole>
      <Position>38</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R39.htm</HtmlFileName>
      <LongName>9955516 - Disclosure - Income taxes (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/IncometaxesTables</Role>
      <ShortName>Income taxes (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.amgen.com/role/Incometaxes</ParentRole>
      <Position>39</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R40.htm</HtmlFileName>
      <LongName>9955517 - Disclosure - Earnings per share (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/EarningspershareTables</Role>
      <ShortName>Earnings per share (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.amgen.com/role/Earningspershare</ParentRole>
      <Position>40</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R41.htm</HtmlFileName>
      <LongName>9955518 - Disclosure - Investments (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/InvestmentsTables</Role>
      <ShortName>Investments (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.amgen.com/role/Investments</ParentRole>
      <Position>41</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R42.htm</HtmlFileName>
      <LongName>9955519 - Disclosure - Inventories (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/InventoriesTables</Role>
      <ShortName>Inventories (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.amgen.com/role/Inventories</ParentRole>
      <Position>42</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R43.htm</HtmlFileName>
      <LongName>9955520 - Disclosure - Property, plant and equipment (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/PropertyplantandequipmentTables</Role>
      <ShortName>Property, plant and equipment (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.amgen.com/role/Propertyplantandequipment</ParentRole>
      <Position>43</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R44.htm</HtmlFileName>
      <LongName>9955521 - Disclosure - Goodwill and other intangible assets (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/GoodwillandotherintangibleassetsTables</Role>
      <ShortName>Goodwill and other intangible assets (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.amgen.com/role/Goodwillandotherintangibleassets</ParentRole>
      <Position>44</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R45.htm</HtmlFileName>
      <LongName>9955522 - Disclosure - Leases (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/LeasesTables</Role>
      <ShortName>Leases (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.amgen.com/role/Leases</ParentRole>
      <Position>45</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R46.htm</HtmlFileName>
      <LongName>9955523 - Disclosure - Other current assets and accrued liabilities (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/OthercurrentassetsandaccruedliabilitiesTables</Role>
      <ShortName>Other current assets and accrued liabilities (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.amgen.com/role/Othercurrentassetsandaccruedliabilities</ParentRole>
      <Position>46</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R47.htm</HtmlFileName>
      <LongName>9955524 - Disclosure - Financing arrangements (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/FinancingarrangementsTables</Role>
      <ShortName>Financing arrangements (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.amgen.com/role/Financingarrangements</ParentRole>
      <Position>47</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R48.htm</HtmlFileName>
      <LongName>9955525 - Disclosure - Stockholders' equity (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/StockholdersequityTables</Role>
      <ShortName>Stockholders' equity (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.amgen.com/role/Stockholdersequity</ParentRole>
      <Position>48</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R49.htm</HtmlFileName>
      <LongName>9955526 - Disclosure - Fair value measurement (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/FairvaluemeasurementTables</Role>
      <ShortName>Fair value measurement (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.amgen.com/role/Fairvaluemeasurement</ParentRole>
      <Position>49</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R50.htm</HtmlFileName>
      <LongName>9955527 - Disclosure - Derivative instruments (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/DerivativeinstrumentsTables</Role>
      <ShortName>Derivative instruments (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.amgen.com/role/Derivativeinstruments</ParentRole>
      <Position>50</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R51.htm</HtmlFileName>
      <LongName>9955528 - Disclosure - Summary of significant accounting policies - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/SummaryofsignificantaccountingpoliciesNarrativeDetails</Role>
      <ShortName>Summary of significant accounting policies - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>51</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R52.htm</HtmlFileName>
      <LongName>9955529 - Disclosure - Segment and other information - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/SegmentandotherinformationNarrativeDetails</Role>
      <ShortName>Segment and other information - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>52</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R53.htm</HtmlFileName>
      <LongName>9955530 - Disclosure - Segment and other information - Schedule of Reconciliation of Segment Net Income to Consolidated Net Income (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/SegmentandotherinformationScheduleofReconciliationofSegmentNetIncometoConsolidatedNetIncomeDetails</Role>
      <ShortName>Segment and other information - Schedule of Reconciliation of Segment Net Income to Consolidated Net Income (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>53</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R54.htm</HtmlFileName>
      <LongName>9955531 - Disclosure - Revenues - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/RevenuesNarrativeDetails</Role>
      <ShortName>Revenues - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>54</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R55.htm</HtmlFileName>
      <LongName>9955532 - Disclosure - Revenues - Schedule of Disaggregation of Revenue by Product and by Geographic Area (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/RevenuesScheduleofDisaggregationofRevenuebyProductandbyGeographicAreaDetails</Role>
      <ShortName>Revenues - Schedule of Disaggregation of Revenue by Product and by Geographic Area (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>55</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R56.htm</HtmlFileName>
      <LongName>9955533 - Disclosure - Revenues - Schedule of Revenues Earned from Major Customers (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/RevenuesScheduleofRevenuesEarnedfromMajorCustomersDetails</Role>
      <ShortName>Revenues - Schedule of Revenues Earned from Major Customers (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>56</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R57.htm</HtmlFileName>
      <LongName>9955534 - Disclosure - Acquisitions - Acquisition of Horizon Therapeutics plc (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/AcquisitionsAcquisitionofHorizonTherapeuticsplcDetails</Role>
      <ShortName>Acquisitions - Acquisition of Horizon Therapeutics plc (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>57</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R58.htm</HtmlFileName>
      <LongName>9955535 - Disclosure - Acquisitions - Schedule of Business Acquisitions, by Acquisition (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/AcquisitionsScheduleofBusinessAcquisitionsbyAcquisitionDetails</Role>
      <ShortName>Acquisitions - Schedule of Business Acquisitions, by Acquisition (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>58</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R59.htm</HtmlFileName>
      <LongName>9955536 - Disclosure - Acquisitions - Schedule of Supplemental Pro Forma Financial Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/AcquisitionsScheduleofSupplementalProFormaFinancialInformationDetails</Role>
      <ShortName>Acquisitions - Schedule of Supplemental Pro Forma Financial Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>59</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R60.htm</HtmlFileName>
      <LongName>9955537 - Disclosure - Stock-based compensation - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/StockbasedcompensationNarrativeDetails</Role>
      <ShortName>Stock-based compensation - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>60</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R61.htm</HtmlFileName>
      <LongName>9955538 - Disclosure - Stock-based compensation - Schedule of Components of Stock-based Compensation Expense (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/StockbasedcompensationScheduleofComponentsofStockbasedCompensationExpenseDetails</Role>
      <ShortName>Stock-based compensation - Schedule of Components of Stock-based Compensation Expense (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>61</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R62.htm</HtmlFileName>
      <LongName>9955539 - Disclosure - Stock-based compensation - Schedule of RSUs (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/StockbasedcompensationScheduleofRSUsDetails</Role>
      <ShortName>Stock-based compensation - Schedule of RSUs (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>62</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R63.htm</HtmlFileName>
      <LongName>9955540 - Disclosure - Stock-based compensation - Schedule of Stock Option Assumptions (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/StockbasedcompensationScheduleofStockOptionAssumptionsDetails</Role>
      <ShortName>Stock-based compensation - Schedule of Stock Option Assumptions (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>63</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R64.htm</HtmlFileName>
      <LongName>9955541 - Disclosure - Stock-based compensation - Schedule of Stock Options (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/StockbasedcompensationScheduleofStockOptionsDetails</Role>
      <ShortName>Stock-based compensation - Schedule of Stock Options (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>64</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R65.htm</HtmlFileName>
      <LongName>9955542 - Disclosure - Stock-based compensation - Schedule of Weighted-Average Assumptions (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/StockbasedcompensationScheduleofWeightedAverageAssumptionsDetails</Role>
      <ShortName>Stock-based compensation - Schedule of Weighted-Average Assumptions (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>65</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R66.htm</HtmlFileName>
      <LongName>9955543 - Disclosure - Defined contribution plan - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/DefinedcontributionplanNarrativeDetails</Role>
      <ShortName>Defined contribution plan - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>66</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R67.htm</HtmlFileName>
      <LongName>9955544 - Disclosure - Income taxes - Schedule of Income before Income Tax, Domestic and Foreign (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/IncometaxesScheduleofIncomebeforeIncomeTaxDomesticandForeignDetails</Role>
      <ShortName>Income taxes - Schedule of Income before Income Tax, Domestic and Foreign (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>67</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R68.htm</HtmlFileName>
      <LongName>9955545 - Disclosure - Income taxes - Schedule of Provision for Income Taxes (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/IncometaxesScheduleofProvisionforIncomeTaxesDetails</Role>
      <ShortName>Income taxes - Schedule of Provision for Income Taxes (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>68</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R69.htm</HtmlFileName>
      <LongName>9955546 - Disclosure - Income taxes - Schedule of Deferred Tax Assets and Liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/IncometaxesScheduleofDeferredTaxAssetsandLiabilitiesDetails</Role>
      <ShortName>Income taxes - Schedule of Deferred Tax Assets and Liabilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>69</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R70.htm</HtmlFileName>
      <LongName>9955547 - Disclosure - Income taxes - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/IncometaxesNarrativeDetails</Role>
      <ShortName>Income taxes - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>70</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R71.htm</HtmlFileName>
      <LongName>9955548 - Disclosure - Income taxes - Schedule of Reconciliation of Total Gross Amounts of UTBs (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/IncometaxesScheduleofReconciliationofTotalGrossAmountsofUTBsDetails</Role>
      <ShortName>Income taxes - Schedule of Reconciliation of Total Gross Amounts of UTBs (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>71</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R72.htm</HtmlFileName>
      <LongName>9955549 - Disclosure - Income taxes - Tax Rate Reconciliation (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/IncometaxesTaxRateReconciliationDetails</Role>
      <ShortName>Income taxes - Tax Rate Reconciliation (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>72</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R73.htm</HtmlFileName>
      <LongName>9955550 - Disclosure - Income taxes - Schedule of Reconciliation of Federal Statutory Tax Rate (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/IncometaxesScheduleofReconciliationofFederalStatutoryTaxRateDetails</Role>
      <ShortName>Income taxes - Schedule of Reconciliation of Federal Statutory Tax Rate (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>73</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R74.htm</HtmlFileName>
      <LongName>9955551 - Disclosure - Income taxes - Schedule of Income Taxes Paid (Net of Refunds Received (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/IncometaxesScheduleofIncomeTaxesPaidNetofRefundsReceivedDetails</Role>
      <ShortName>Income taxes - Schedule of Income Taxes Paid (Net of Refunds Received (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>74</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R75.htm</HtmlFileName>
      <LongName>9955552 - Disclosure - Earnings per share - Schedule of Computation for Basic and Diluted Earnings per Share (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/EarningspershareScheduleofComputationforBasicandDilutedEarningsperShareDetails</Role>
      <ShortName>Earnings per share - Schedule of Computation for Basic and Diluted Earnings per Share (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>75</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R76.htm</HtmlFileName>
      <LongName>9955553 - Disclosure - Collaborations - AstraZeneca PLC (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/CollaborationsAstraZenecaPLCDetails</Role>
      <ShortName>Collaborations - AstraZeneca PLC (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>76</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R77.htm</HtmlFileName>
      <LongName>9955554 - Disclosure - Collaborations - UCB (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/CollaborationsUCBDetails</Role>
      <ShortName>Collaborations - UCB (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>77</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R78.htm</HtmlFileName>
      <LongName>9955555 - Disclosure - Collaborations - BeOne (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/CollaborationsBeOneDetails</Role>
      <ShortName>Collaborations - BeOne (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>78</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R79.htm</HtmlFileName>
      <LongName>9955556 - Disclosure - Collaborations - Kyowa Kirin (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/CollaborationsKyowaKirinDetails</Role>
      <ShortName>Collaborations - Kyowa Kirin (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>79</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R80.htm</HtmlFileName>
      <LongName>9955557 - Disclosure - Investments - Schedule of Available-For-Sale Investments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/InvestmentsScheduleofAvailableForSaleInvestmentsDetails</Role>
      <ShortName>Investments - Schedule of Available-For-Sale Investments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>80</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R81.htm</HtmlFileName>
      <LongName>9955558 - Disclosure - Investments - Schedule of Fair Values by Classification (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/InvestmentsScheduleofFairValuesbyClassificationDetails</Role>
      <ShortName>Investments - Schedule of Fair Values by Classification (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>81</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R82.htm</HtmlFileName>
      <LongName>9955559 - Disclosure - Investments - Available-For-Sale (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/InvestmentsAvailableForSaleDetails</Role>
      <ShortName>Investments - Available-For-Sale (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>82</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R83.htm</HtmlFileName>
      <LongName>9955560 - Disclosure - Investments - BeOne (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/InvestmentsBeOneDetails</Role>
      <ShortName>Investments - BeOne (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>83</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R84.htm</HtmlFileName>
      <LongName>9955561 - Disclosure - Investments - Other Equity Securities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/InvestmentsOtherEquitySecuritiesDetails</Role>
      <ShortName>Investments - Other Equity Securities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>84</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R85.htm</HtmlFileName>
      <LongName>9955562 - Disclosure - Investments - Neumora Therapeutics, Inc. (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/InvestmentsNeumoraTherapeuticsIncDetails</Role>
      <ShortName>Investments - Neumora Therapeutics, Inc. (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>85</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R86.htm</HtmlFileName>
      <LongName>9955563 - Disclosure - Investments - Limited Partnership Investments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/InvestmentsLimitedPartnershipInvestmentsDetails</Role>
      <ShortName>Investments - Limited Partnership Investments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>86</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R87.htm</HtmlFileName>
      <LongName>9955564 - Disclosure - Inventories (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/InventoriesDetails</Role>
      <ShortName>Inventories (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.amgen.com/role/InventoriesTables</ParentRole>
      <Position>87</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R88.htm</HtmlFileName>
      <LongName>9955565 - Disclosure - Property, plant and equipment - Schedule of Property, Plant and Equipment (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/PropertyplantandequipmentScheduleofPropertyPlantandEquipmentDetails</Role>
      <ShortName>Property, plant and equipment - Schedule of Property, Plant and Equipment (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>88</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R89.htm</HtmlFileName>
      <LongName>9955566 - Disclosure - Property, plant and equipment - Schedule of Property, Plant and Equipment by Geographic Area (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/PropertyplantandequipmentScheduleofPropertyPlantandEquipmentbyGeographicAreaDetails</Role>
      <ShortName>Property, plant and equipment - Schedule of Property, Plant and Equipment by Geographic Area (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>89</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R90.htm</HtmlFileName>
      <LongName>9955567 - Disclosure - Goodwill and other intangible assets - Schedule of Goodwill (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/GoodwillandotherintangibleassetsScheduleofGoodwillDetails</Role>
      <ShortName>Goodwill and other intangible assets - Schedule of Goodwill (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>90</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R91.htm</HtmlFileName>
      <LongName>9955568 - Disclosure - Goodwill and other intangible assets - Schedule of Other Intangible Assets (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/GoodwillandotherintangibleassetsScheduleofOtherIntangibleAssetsDetails</Role>
      <ShortName>Goodwill and other intangible assets - Schedule of Other Intangible Assets (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>91</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R92.htm</HtmlFileName>
      <LongName>9955569 - Disclosure - Goodwill and other intangible assets - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/GoodwillandotherintangibleassetsNarrativeDetails</Role>
      <ShortName>Goodwill and other intangible assets - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>92</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R93.htm</HtmlFileName>
      <LongName>9955570 - Disclosure - Leases - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/LeasesNarrativeDetails</Role>
      <ShortName>Leases - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>93</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R94.htm</HtmlFileName>
      <LongName>9955571 - Disclosure - Leases - Schedule of Operating Leases (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/LeasesScheduleofOperatingLeasesDetails</Role>
      <ShortName>Leases - Schedule of Operating Leases (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>94</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R95.htm</HtmlFileName>
      <LongName>9955572 - Disclosure - Leases - Schedule of Components of Lease Costs (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/LeasesScheduleofComponentsofLeaseCostsDetails</Role>
      <ShortName>Leases - Schedule of Components of Lease Costs (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>95</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R96.htm</HtmlFileName>
      <LongName>9955573 - Disclosure - Leases - Schedule of Maturities of Lease Liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/LeasesScheduleofMaturitiesofLeaseLiabilitiesDetails</Role>
      <ShortName>Leases - Schedule of Maturities of Lease Liabilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>96</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R97.htm</HtmlFileName>
      <LongName>9955574 - Disclosure - Leases - Schedule of Weighted Average Remaining Lease Terms &amp; Discount Rates (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/LeasesScheduleofWeightedAverageRemainingLeaseTermsDiscountRatesDetails</Role>
      <ShortName>Leases - Schedule of Weighted Average Remaining Lease Terms &amp; Discount Rates (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>97</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R98.htm</HtmlFileName>
      <LongName>9955575 - Disclosure - Leases - Schedule of Cash and Noncash Information of Leases (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/LeasesScheduleofCashandNoncashInformationofLeasesDetails</Role>
      <ShortName>Leases - Schedule of Cash and Noncash Information of Leases (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>98</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R99.htm</HtmlFileName>
      <LongName>9955576 - Disclosure - Other current assets and accrued liabilities - Schedule of Other Current Assets (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/OthercurrentassetsandaccruedliabilitiesScheduleofOtherCurrentAssetsDetails</Role>
      <ShortName>Other current assets and accrued liabilities - Schedule of Other Current Assets (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>99</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R100.htm</HtmlFileName>
      <LongName>9955577 - Disclosure - Other current assets and accrued liabilities - Schedule of Accrued Liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/OthercurrentassetsandaccruedliabilitiesScheduleofAccruedLiabilitiesDetails</Role>
      <ShortName>Other current assets and accrued liabilities - Schedule of Accrued Liabilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>100</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R101.htm</HtmlFileName>
      <LongName>9955578 - Disclosure - Financing arrangements - Schedule of Borrowings (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/FinancingarrangementsScheduleofBorrowingsDetails</Role>
      <ShortName>Financing arrangements - Schedule of Borrowings (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>101</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R102.htm</HtmlFileName>
      <LongName>9955579 - Disclosure - Financing arrangements - Miscellaneous (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/FinancingarrangementsMiscellaneousDetails</Role>
      <ShortName>Financing arrangements - Miscellaneous (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>102</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R103.htm</HtmlFileName>
      <LongName>9955580 - Disclosure - Financing arrangements - Schedule of Debt Issuances (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/FinancingarrangementsScheduleofDebtIssuancesDetails</Role>
      <ShortName>Financing arrangements - Schedule of Debt Issuances (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>103</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R104.htm</HtmlFileName>
      <LongName>9955581 - Disclosure - Financing arrangements - Debt Issuances and Acquisition-Related Financing (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/FinancingarrangementsDebtIssuancesandAcquisitionRelatedFinancingDetails</Role>
      <ShortName>Financing arrangements - Debt Issuances and Acquisition-Related Financing (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>104</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R105.htm</HtmlFileName>
      <LongName>9955582 - Disclosure - Financing arrangements - Debt Extinguishment (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/FinancingarrangementsDebtExtinguishmentDetails</Role>
      <ShortName>Financing arrangements - Debt Extinguishment (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>105</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R106.htm</HtmlFileName>
      <LongName>9955583 - Disclosure - Financing arrangements - Debt Repayments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/FinancingarrangementsDebtRepaymentsDetails</Role>
      <ShortName>Financing arrangements - Debt Repayments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>106</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R107.htm</HtmlFileName>
      <LongName>9955584 - Disclosure - Financing arrangements - Cross-Currency Swaps (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/FinancingarrangementsCrossCurrencySwapsDetails</Role>
      <ShortName>Financing arrangements - Cross-Currency Swaps (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>107</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R108.htm</HtmlFileName>
      <LongName>9955585 - Disclosure - Financing arrangements - Shelf Registration Statement and Other Facilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/FinancingarrangementsShelfRegistrationStatementandOtherFacilitiesDetails</Role>
      <ShortName>Financing arrangements - Shelf Registration Statement and Other Facilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>108</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R109.htm</HtmlFileName>
      <LongName>9955586 - Disclosure - Financing arrangements - Schedule of Contractual Maturities of Long-term Debt (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/FinancingarrangementsScheduleofContractualMaturitiesofLongtermDebtDetails</Role>
      <ShortName>Financing arrangements - Schedule of Contractual Maturities of Long-term Debt (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>109</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R110.htm</HtmlFileName>
      <LongName>9955587 - Disclosure - Financing arrangements - Interest Costs (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/FinancingarrangementsInterestCostsDetails</Role>
      <ShortName>Financing arrangements - Interest Costs (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>110</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R111.htm</HtmlFileName>
      <LongName>9955588 - Disclosure - Stockholders' equity - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/StockholdersequityNarrativeDetails</Role>
      <ShortName>Stockholders' equity - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>111</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R112.htm</HtmlFileName>
      <LongName>9955589 - Disclosure - Stockholders' equity - Schedule of Components of AOCI (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/StockholdersequityScheduleofComponentsofAOCIDetails</Role>
      <ShortName>Stockholders' equity - Schedule of Components of AOCI (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>112</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R113.htm</HtmlFileName>
      <LongName>9955590 - Disclosure - Stockholders' equity - Schedule of Reclassifications Out of AOCI (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/StockholdersequityScheduleofReclassificationsOutofAOCIDetails</Role>
      <ShortName>Stockholders' equity - Schedule of Reclassifications Out of AOCI (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>113</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R114.htm</HtmlFileName>
      <LongName>9955591 - Disclosure - Fair value measurement - Fair Value of Financial Assets and Liabilities on Recurring Basis (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/FairvaluemeasurementFairValueofFinancialAssetsandLiabilitiesonRecurringBasisDetails</Role>
      <ShortName>Fair value measurement - Fair Value of Financial Assets and Liabilities on Recurring Basis (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>114</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R115.htm</HtmlFileName>
      <LongName>9955592 - Disclosure - Fair value measurement - Schedule of Contingent Consideration Obligations (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/FairvaluemeasurementScheduleofContingentConsiderationObligationsDetails</Role>
      <ShortName>Fair value measurement - Schedule of Contingent Consideration Obligations (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>115</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R116.htm</HtmlFileName>
      <LongName>9955593 - Disclosure - Fair value measurement - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/FairvaluemeasurementNarrativeDetails</Role>
      <ShortName>Fair value measurement - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>116</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R117.htm</HtmlFileName>
      <LongName>9955594 - Disclosure - Derivative instruments - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/DerivativeinstrumentsNarrativeDetails</Role>
      <ShortName>Derivative instruments - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>117</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R118.htm</HtmlFileName>
      <LongName>9955595 - Disclosure - Derivative instruments - Schedule of Cross-Currency Swaps (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/DerivativeinstrumentsScheduleofCrossCurrencySwapsDetails</Role>
      <ShortName>Derivative instruments - Schedule of Cross-Currency Swaps (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>118</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R119.htm</HtmlFileName>
      <LongName>9955596 - Disclosure - Derivative instruments - Schedule of Effective Portion of Unrealized Gain (Loss) Recognized in AOCI (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/DerivativeinstrumentsScheduleofEffectivePortionofUnrealizedGainLossRecognizedinAOCIDetails</Role>
      <ShortName>Derivative instruments - Schedule of Effective Portion of Unrealized Gain (Loss) Recognized in AOCI (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>119</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R120.htm</HtmlFileName>
      <LongName>9955597 - Disclosure - Derivative instruments - Schedule of Interest Rate Derivatives (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/DerivativeinstrumentsScheduleofInterestRateDerivativesDetails</Role>
      <ShortName>Derivative instruments - Schedule of Interest Rate Derivatives (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>120</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R121.htm</HtmlFileName>
      <LongName>9955598 - Disclosure - Derivative instruments - Schedule of Hedged Liabilities and Cumulative Amount (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/DerivativeinstrumentsScheduleofHedgedLiabilitiesandCumulativeAmountDetails</Role>
      <ShortName>Derivative instruments - Schedule of Hedged Liabilities and Cumulative Amount (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>121</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R122.htm</HtmlFileName>
      <LongName>9955599 - Disclosure - Derivative instruments - Schedule of Income and Expense Line Items (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/DerivativeinstrumentsScheduleofIncomeandExpenseLineItemsDetails</Role>
      <ShortName>Derivative instruments - Schedule of Income and Expense Line Items (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>122</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R123.htm</HtmlFileName>
      <LongName>9955600 - Disclosure - Derivative instruments - Schedule of Fair Value of Derivatives (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/DerivativeinstrumentsScheduleofFairValueofDerivativesDetails</Role>
      <ShortName>Derivative instruments - Schedule of Fair Value of Derivatives (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>123</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R124.htm</HtmlFileName>
      <LongName>9955601 - Disclosure - Contingencies and commitments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/ContingenciesandcommitmentsDetails</Role>
      <ShortName>Contingencies and commitments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.amgen.com/role/Contingenciesandcommitments</ParentRole>
      <Position>124</Position>
    </Report>
    <Report instance="amgn-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R125.htm</HtmlFileName>
      <LongName>9955602 - Disclosure - SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amgen.com/role/SCHEDULEIIVALUATIONANDQUALIFYINGACCOUNTSDetails</Role>
      <ShortName>SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.amgen.com/role/SCHEDULEIIVALUATIONANDQUALIFYINGACCOUNTS</ParentRole>
      <Position>125</Position>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <LongName>All Reports</LongName>
      <ReportType>Book</ReportType>
      <ShortName>All Reports</ShortName>
    </Report>
  </MyReports>
  <InputFiles>
    <File doctype="10-K" isDefinitelyFs="true" isUsgaap="true" original="amgn-20251231.htm">amgn-20251231.htm</File>
    <File>amgn-20251231.xsd</File>
    <File>amgn-20251231_cal.xml</File>
    <File>amgn-20251231_def.xml</File>
    <File>amgn-20251231_lab.xml</File>
    <File>amgn-20251231_pre.xml</File>
  </InputFiles>
  <SupplementalFiles>
    <File>amgn-20251231_g1.jpg</File>
    <File>amgn-20251231_g2.jpg</File>
  </SupplementalFiles>
  <BaseTaxonomies>
    <BaseTaxonomy items="1">http://fasb.org/srt/2025</BaseTaxonomy>
    <BaseTaxonomy items="1811">http://fasb.org/us-gaap/2025</BaseTaxonomy>
    <BaseTaxonomy items="15">http://xbrl.sec.gov/cyd/2025</BaseTaxonomy>
    <BaseTaxonomy items="43">http://xbrl.sec.gov/dei/2025</BaseTaxonomy>
    <BaseTaxonomy items="5">http://xbrl.sec.gov/ecd/2025</BaseTaxonomy>
  </BaseTaxonomies>
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
