<?xml version='1.0' encoding='utf-8'?>
<FilingSummary>
  <Version>3.22.2.2</Version>
  <ProcessingTime/>
  <ReportFormat>html</ReportFormat>
  <ContextCount>618</ContextCount>
  <ElementCount>408</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>true</FootnotesReported>
  <SegmentCount>175</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>10</UnitCount>
  <MyReports>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>0000001 - Document - Cover Page</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/CoverPage</Role>
      <ShortName>Cover Page</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>1</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>0000002 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF INCOME (UNAUDITED)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/CONDENSEDCONSOLIDATEDSTATEMENTSOFINCOMEUNAUDITED</Role>
      <ShortName>CONDENSED CONSOLIDATED STATEMENTS OF INCOME (UNAUDITED)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>2</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>0000003 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/CONDENSEDCONSOLIDATEDSTATEMENTSOFCOMPREHENSIVEINCOMEUNAUDITED</Role>
      <ShortName>CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>3</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>0000004 - Statement - CONDENSED CONSOLIDATED BALANCE SHEETS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/CONDENSEDCONSOLIDATEDBALANCESHEETS</Role>
      <ShortName>CONDENSED CONSOLIDATED BALANCE SHEETS</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>4</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R5.htm</HtmlFileName>
      <LongName>0000005 - Statement - CONDENSED CONSOLIDATED BALANCE SHEETS (PARENTHETICAL)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/CONDENSEDCONSOLIDATEDBALANCESHEETSPARENTHETICAL</Role>
      <ShortName>CONDENSED CONSOLIDATED BALANCE SHEETS (PARENTHETICAL)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>5</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R6.htm</HtmlFileName>
      <LongName>0000006 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF EQUITY (UNAUDITED)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/CONDENSEDCONSOLIDATEDSTATEMENTSOFEQUITYUNAUDITED</Role>
      <ShortName>CONDENSED CONSOLIDATED STATEMENTS OF EQUITY (UNAUDITED)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>6</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>0000007 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF EQUITY (UNAUDITED) (PARENTHETICAL)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/CONDENSEDCONSOLIDATEDSTATEMENTSOFEQUITYUNAUDITEDPARENTHETICAL</Role>
      <ShortName>CONDENSED CONSOLIDATED STATEMENTS OF EQUITY (UNAUDITED) (PARENTHETICAL)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>7</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>0000008 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/CONDENSEDCONSOLIDATEDSTATEMENTSOFCASHFLOWSUNAUDITED</Role>
      <ShortName>CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>8</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.htm</HtmlFileName>
      <LongName>0000009 - Disclosure - Basis of Presentation and Significant Accounting Policies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/BasisofPresentationandSignificantAccountingPolicies</Role>
      <ShortName>Basis of Presentation and Significant Accounting Policies</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>9</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R10.htm</HtmlFileName>
      <LongName>0000010 - Disclosure - Acquisition, Discontinued Operations, Equity-Method Investment and Collaborative Arrangement</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/AcquisitionDiscontinuedOperationsEquityMethodInvestmentandCollaborativeArrangement</Role>
      <ShortName>Acquisition, Discontinued Operations, Equity-Method Investment and Collaborative Arrangement</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>10</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>0000011 - Disclosure - Restructuring Charges and Other Costs Associated with Acquisitions and Cost-Reduction/Productivity Initiatives</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/RestructuringChargesandOtherCostsAssociatedwithAcquisitionsandCostReductionProductivityInitiatives</Role>
      <ShortName>Restructuring Charges and Other Costs Associated with Acquisitions and Cost-Reduction/Productivity Initiatives</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>11</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>0000012 - Disclosure - Other (Income)/Deductions - Net</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/OtherIncomeDeductionsNet</Role>
      <ShortName>Other (Income)/Deductions - Net</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>12</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>0000013 - Disclosure - Tax Matters</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/TaxMatters</Role>
      <ShortName>Tax Matters</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>13</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>0000014 - Disclosure - Accumulated Other Comprehensive Loss, Excluding Noncontrolling Interests</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/AccumulatedOtherComprehensiveLossExcludingNoncontrollingInterests</Role>
      <ShortName>Accumulated Other Comprehensive Loss, Excluding Noncontrolling Interests</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>14</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R15.htm</HtmlFileName>
      <LongName>0000015 - Disclosure - Financial Instruments</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/FinancialInstruments</Role>
      <ShortName>Financial Instruments</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>15</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>0000016 - Disclosure - Other Financial Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/OtherFinancialInformation</Role>
      <ShortName>Other Financial Information</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>16</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>0000017 - Disclosure - Identifiable Intangible Assets</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/IdentifiableIntangibleAssets</Role>
      <ShortName>Identifiable Intangible Assets</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>17</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R18.htm</HtmlFileName>
      <LongName>0000018 - Disclosure - Pension and Postretirement Benefit Plans</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/PensionandPostretirementBenefitPlans</Role>
      <ShortName>Pension and Postretirement Benefit Plans</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>18</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R19.htm</HtmlFileName>
      <LongName>0000019 - Disclosure - Earnings Per Common Share Attributable to Pfizer Inc. Common Shareholders</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/EarningsPerCommonShareAttributabletoPfizerIncCommonShareholders</Role>
      <ShortName>Earnings Per Common Share Attributable to Pfizer Inc. Common Shareholders</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>19</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R20.htm</HtmlFileName>
      <LongName>0000020 - Disclosure - Contingencies and Certain Commitments</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/ContingenciesandCertainCommitments</Role>
      <ShortName>Contingencies and Certain Commitments</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>20</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R21.htm</HtmlFileName>
      <LongName>0000021 - Disclosure - Segment, Geographic and Other Revenue Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/SegmentGeographicandOtherRevenueInformation</Role>
      <ShortName>Segment, Geographic and Other Revenue Information</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>21</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R22.htm</HtmlFileName>
      <LongName>0000022 - Disclosure - Basis of Presentation and Significant Accounting Policies (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/BasisofPresentationandSignificantAccountingPoliciesPolicies</Role>
      <ShortName>Basis of Presentation and Significant Accounting Policies (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <ParentRole>http://www.pfizer.com/role/BasisofPresentationandSignificantAccountingPolicies</ParentRole>
      <Position>22</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R23.htm</HtmlFileName>
      <LongName>0000023 - Disclosure - Basis of Presentation and Significant Accounting Policies (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/BasisofPresentationandSignificantAccountingPoliciesTables</Role>
      <ShortName>Basis of Presentation and Significant Accounting Policies (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.pfizer.com/role/BasisofPresentationandSignificantAccountingPolicies</ParentRole>
      <Position>23</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R24.htm</HtmlFileName>
      <LongName>0000024 - Disclosure - Acquisition, Discontinued Operations, Equity-Method Investment and Collaborative Arrangement (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/AcquisitionDiscontinuedOperationsEquityMethodInvestmentandCollaborativeArrangementTables</Role>
      <ShortName>Acquisition, Discontinued Operations, Equity-Method Investment and Collaborative Arrangement (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.pfizer.com/role/AcquisitionDiscontinuedOperationsEquityMethodInvestmentandCollaborativeArrangement</ParentRole>
      <Position>24</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>0000025 - Disclosure - Restructuring Charges and Other Costs Associated with Acquisitions and Cost-Reduction/Productivity Initiatives (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/RestructuringChargesandOtherCostsAssociatedwithAcquisitionsandCostReductionProductivityInitiativesTables</Role>
      <ShortName>Restructuring Charges and Other Costs Associated with Acquisitions and Cost-Reduction/Productivity Initiatives (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.pfizer.com/role/RestructuringChargesandOtherCostsAssociatedwithAcquisitionsandCostReductionProductivityInitiatives</ParentRole>
      <Position>25</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>0000026 - Disclosure - Other (Income)/Deductions - Net (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/OtherIncomeDeductionsNetTables</Role>
      <ShortName>Other (Income)/Deductions - Net (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.pfizer.com/role/OtherIncomeDeductionsNet</ParentRole>
      <Position>26</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R27.htm</HtmlFileName>
      <LongName>0000027 - Disclosure - Tax Matters (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/TaxMattersTables</Role>
      <ShortName>Tax Matters (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.pfizer.com/role/TaxMatters</ParentRole>
      <Position>27</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R28.htm</HtmlFileName>
      <LongName>0000028 - Disclosure - Accumulated Other Comprehensive Loss, Excluding Noncontrolling Interests (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/AccumulatedOtherComprehensiveLossExcludingNoncontrollingInterestsTables</Role>
      <ShortName>Accumulated Other Comprehensive Loss, Excluding Noncontrolling Interests (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.pfizer.com/role/AccumulatedOtherComprehensiveLossExcludingNoncontrollingInterests</ParentRole>
      <Position>28</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R29.htm</HtmlFileName>
      <LongName>0000029 - Disclosure - Financial Instruments (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/FinancialInstrumentsTables</Role>
      <ShortName>Financial Instruments (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.pfizer.com/role/FinancialInstruments</ParentRole>
      <Position>29</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R30.htm</HtmlFileName>
      <LongName>0000030 - Disclosure - Other Financial Information (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/OtherFinancialInformationTables</Role>
      <ShortName>Other Financial Information (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.pfizer.com/role/OtherFinancialInformation</ParentRole>
      <Position>30</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R31.htm</HtmlFileName>
      <LongName>0000031 - Disclosure - Identifiable Intangible Assets (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/IdentifiableIntangibleAssetsTables</Role>
      <ShortName>Identifiable Intangible Assets (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.pfizer.com/role/IdentifiableIntangibleAssets</ParentRole>
      <Position>31</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R32.htm</HtmlFileName>
      <LongName>0000032 - Disclosure - Pension and Postretirement Benefit Plans (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/PensionandPostretirementBenefitPlansTables</Role>
      <ShortName>Pension and Postretirement Benefit Plans (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.pfizer.com/role/PensionandPostretirementBenefitPlans</ParentRole>
      <Position>32</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R33.htm</HtmlFileName>
      <LongName>0000033 - Disclosure - Earnings Per Common Share Attributable to Pfizer Inc. Common Shareholders (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/EarningsPerCommonShareAttributabletoPfizerIncCommonShareholdersTables</Role>
      <ShortName>Earnings Per Common Share Attributable to Pfizer Inc. Common Shareholders (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.pfizer.com/role/EarningsPerCommonShareAttributabletoPfizerIncCommonShareholders</ParentRole>
      <Position>33</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R34.htm</HtmlFileName>
      <LongName>0000034 - Disclosure - Segment, Geographic and Other Revenue Information (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/SegmentGeographicandOtherRevenueInformationTables</Role>
      <ShortName>Segment, Geographic and Other Revenue Information (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.pfizer.com/role/SegmentGeographicandOtherRevenueInformation</ParentRole>
      <Position>34</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R35.htm</HtmlFileName>
      <LongName>0000035 - Disclosure - Basis of Presentation and Significant Accounting Policies - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/BasisofPresentationandSignificantAccountingPoliciesNarrativeDetails</Role>
      <ShortName>Basis of Presentation and Significant Accounting Policies - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.pfizer.com/role/BasisofPresentationandSignificantAccountingPoliciesTables</ParentRole>
      <Position>35</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R36.htm</HtmlFileName>
      <LongName>0000036 - Disclosure - Basis of Presentation and Significant Accounting Policies - Schedule of Balance Sheet Classification of Accruals (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/BasisofPresentationandSignificantAccountingPoliciesScheduleofBalanceSheetClassificationofAccrualsDetails</Role>
      <ShortName>Basis of Presentation and Significant Accounting Policies - Schedule of Balance Sheet Classification of Accruals (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>36</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R37.htm</HtmlFileName>
      <LongName>0000037 - Disclosure - Acquisition, Discontinued Operations, Equity-Method Investment and Collaborative Arrangement - Acquisitions Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/AcquisitionDiscontinuedOperationsEquityMethodInvestmentandCollaborativeArrangementAcquisitionsNarrativeDetails</Role>
      <ShortName>Acquisition, Discontinued Operations, Equity-Method Investment and Collaborative Arrangement - Acquisitions Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>37</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R38.htm</HtmlFileName>
      <LongName>0000038 - Disclosure - Acquisition, Discontinued Operations, Equity-Method Investment and Collaborative Arrangement - Discontinued Operations Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/AcquisitionDiscontinuedOperationsEquityMethodInvestmentandCollaborativeArrangementDiscontinuedOperationsNarrativeDetails</Role>
      <ShortName>Acquisition, Discontinued Operations, Equity-Method Investment and Collaborative Arrangement - Discontinued Operations Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>38</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R39.htm</HtmlFileName>
      <LongName>0000039 - Disclosure - Acquisition, Discontinued Operations, Equity-Method Investment and Collaborative Arrangement - Equity Method Investment Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/AcquisitionDiscontinuedOperationsEquityMethodInvestmentandCollaborativeArrangementEquityMethodInvestmentNarrativeDetails</Role>
      <ShortName>Acquisition, Discontinued Operations, Equity-Method Investment and Collaborative Arrangement - Equity Method Investment Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>39</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R40.htm</HtmlFileName>
      <LongName>0000040 - Disclosure - Acquisition, Discontinued Operations, Equity-Method Investment and Collaborative Arrangement - Schedule of Equity-Method Investment (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/AcquisitionDiscontinuedOperationsEquityMethodInvestmentandCollaborativeArrangementScheduleofEquityMethodInvestmentDetails</Role>
      <ShortName>Acquisition, Discontinued Operations, Equity-Method Investment and Collaborative Arrangement - Schedule of Equity-Method Investment (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>40</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R41.htm</HtmlFileName>
      <LongName>0000041 - Disclosure - Acquisition, Discontinued Operations, Equity-Method Investment and Collaborative Arrangement - Collaborative Arrangements (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/AcquisitionDiscontinuedOperationsEquityMethodInvestmentandCollaborativeArrangementCollaborativeArrangementsDetail</Role>
      <ShortName>Acquisition, Discontinued Operations, Equity-Method Investment and Collaborative Arrangement - Collaborative Arrangements (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>41</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R42.htm</HtmlFileName>
      <LongName>0000042 - Disclosure - Restructuring Charges and Other Costs Associated with Acquisitions and Cost-Reduction/Productivity Initiatives - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/RestructuringChargesandOtherCostsAssociatedwithAcquisitionsandCostReductionProductivityInitiativesNarrativeDetails</Role>
      <ShortName>Restructuring Charges and Other Costs Associated with Acquisitions and Cost-Reduction/Productivity Initiatives - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.pfizer.com/role/RestructuringChargesandOtherCostsAssociatedwithAcquisitionsandCostReductionProductivityInitiativesTables</ParentRole>
      <Position>42</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R43.htm</HtmlFileName>
      <LongName>0000043 - Disclosure - Restructuring Charges and Other Costs Associated with Acquisitions and Cost-Reduction/Productivity Initiatives - Schedule of Acquisitions and Cost-Reduction/Productivity Initiatives (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/RestructuringChargesandOtherCostsAssociatedwithAcquisitionsandCostReductionProductivityInitiativesScheduleofAcquisitionsandCostReductionProductivityInitiativesDetail</Role>
      <ShortName>Restructuring Charges and Other Costs Associated with Acquisitions and Cost-Reduction/Productivity Initiatives - Schedule of Acquisitions and Cost-Reduction/Productivity Initiatives (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>43</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R44.htm</HtmlFileName>
      <LongName>0000044 - Disclosure - Restructuring Charges and Other Costs Associated with Acquisitions and Cost-Reduction/Productivity Initiatives - Schedule of Components and Changes in Restructuring Accruals (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/RestructuringChargesandOtherCostsAssociatedwithAcquisitionsandCostReductionProductivityInitiativesScheduleofComponentsandChangesinRestructuringAccrualsDetail</Role>
      <ShortName>Restructuring Charges and Other Costs Associated with Acquisitions and Cost-Reduction/Productivity Initiatives - Schedule of Components and Changes in Restructuring Accruals (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>44</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R45.htm</HtmlFileName>
      <LongName>0000045 - Disclosure - Other (Income)/Deductions - Net - Schedule of Other (Income)/Deductions - Net (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/OtherIncomeDeductionsNetScheduleofOtherIncomeDeductionsNetDetail</Role>
      <ShortName>Other (Income)/Deductions - Net - Schedule of Other (Income)/Deductions - Net (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.pfizer.com/role/OtherIncomeDeductionsNetTables</ParentRole>
      <Position>45</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R46.htm</HtmlFileName>
      <LongName>0000046 - Disclosure - Other (Income)/Deductions - Net - Footnotes (Detail)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.pfizer.com/role/OtherIncomeDeductionsNetFootnotesDetail</Role>
      <ShortName>Other (Income)/Deductions - Net - Footnotes (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.pfizer.com/role/OtherIncomeDeductionsNetTables</ParentRole>
      <Position>46</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R47.htm</HtmlFileName>
      <LongName>0000047 - Disclosure - Other (Income)/Deductions - Net - Schedule of Impaired Intangible Assets (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/OtherIncomeDeductionsNetScheduleofImpairedIntangibleAssetsDetails</Role>
      <ShortName>Other (Income)/Deductions - Net - Schedule of Impaired Intangible Assets (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.pfizer.com/role/OtherIncomeDeductionsNetTables</ParentRole>
      <Position>47</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R48.htm</HtmlFileName>
      <LongName>0000048 - Disclosure - Tax Matters - Narrative (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/TaxMattersNarrativeDetail</Role>
      <ShortName>Tax Matters - Narrative (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>48</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R49.htm</HtmlFileName>
      <LongName>0000049 - Disclosure - Tax Matters - Schedule of Tax Provision/(Benefit) on Other Comprehensive Income (Loss) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/TaxMattersScheduleofTaxProvisionBenefitonOtherComprehensiveIncomeLossDetail</Role>
      <ShortName>Tax Matters - Schedule of Tax Provision/(Benefit) on Other Comprehensive Income (Loss) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>49</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R50.htm</HtmlFileName>
      <LongName>0000050 - Disclosure - Accumulated Other Comprehensive Loss, Excluding Noncontrolling Interests (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/AccumulatedOtherComprehensiveLossExcludingNoncontrollingInterestsDetail</Role>
      <ShortName>Accumulated Other Comprehensive Loss, Excluding Noncontrolling Interests (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.pfizer.com/role/AccumulatedOtherComprehensiveLossExcludingNoncontrollingInterestsTables</ParentRole>
      <Position>50</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R51.htm</HtmlFileName>
      <LongName>0000051 - Disclosure - Financial Instruments - Financial Assets and Liabilities Measured at Fair Value on a Recurring Basis (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/FinancialInstrumentsFinancialAssetsandLiabilitiesMeasuredatFairValueonaRecurringBasisDetail</Role>
      <ShortName>Financial Instruments - Financial Assets and Liabilities Measured at Fair Value on a Recurring Basis (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>51</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R52.htm</HtmlFileName>
      <LongName>0000052 - Disclosure - Financial Instruments - Financial Liabilities Not Measured at Fair Value on a Recurring Basis (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/FinancialInstrumentsFinancialLiabilitiesNotMeasuredatFairValueonaRecurringBasisDetails</Role>
      <ShortName>Financial Instruments - Financial Liabilities Not Measured at Fair Value on a Recurring Basis (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>52</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R53.htm</HtmlFileName>
      <LongName>0000053 - Disclosure - Financial Instruments - Investments by Classification Type (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/FinancialInstrumentsInvestmentsbyClassificationTypeDetails</Role>
      <ShortName>Financial Instruments - Investments by Classification Type (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>53</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R54.htm</HtmlFileName>
      <LongName>0000054 - Disclosure - Financial Instruments - Schedule of Investment Securities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/FinancialInstrumentsScheduleofInvestmentSecuritiesDetails</Role>
      <ShortName>Financial Instruments - Schedule of Investment Securities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>54</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R55.htm</HtmlFileName>
      <LongName>0000055 - Disclosure - Financial Instruments - Investments - Unrealized Gains and Losses Related to Equity Securities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/FinancialInstrumentsInvestmentsUnrealizedGainsandLossesRelatedtoEquitySecuritiesDetails</Role>
      <ShortName>Financial Instruments - Investments - Unrealized Gains and Losses Related to Equity Securities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>55</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R56.htm</HtmlFileName>
      <LongName>0000056 - Disclosure - Financial Instruments - Investments - Unrealized Gains and Losses Related to Equity Securities - Footnotes (Details)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.pfizer.com/role/FinancialInstrumentsInvestmentsUnrealizedGainsandLossesRelatedtoEquitySecuritiesFootnotesDetails</Role>
      <ShortName>Financial Instruments - Investments - Unrealized Gains and Losses Related to Equity Securities - Footnotes (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>56</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R57.htm</HtmlFileName>
      <LongName>0000057 - Disclosure - Financial Instruments - Short-term Borrowings (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/FinancialInstrumentsShorttermBorrowingsDetails</Role>
      <ShortName>Financial Instruments - Short-term Borrowings (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>57</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R58.htm</HtmlFileName>
      <LongName>0000058 - Disclosure - Financial Instruments - Long-Term Debt (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/FinancialInstrumentsLongTermDebtDetails</Role>
      <ShortName>Financial Instruments - Long-Term Debt (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>58</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R59.htm</HtmlFileName>
      <LongName>0000059 - Disclosure - Financial Instruments - Derivative Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/FinancialInstrumentsDerivativeNarrativeDetails</Role>
      <ShortName>Financial Instruments - Derivative Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>59</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R60.htm</HtmlFileName>
      <LongName>0000060 - Disclosure - Financial Instruments - Fair Value of Derivative Financial Instruments and Related Notional Amounts (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/FinancialInstrumentsFairValueofDerivativeFinancialInstrumentsandRelatedNotionalAmountsDetails</Role>
      <ShortName>Financial Instruments - Fair Value of Derivative Financial Instruments and Related Notional Amounts (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>60</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R61.htm</HtmlFileName>
      <LongName>0000061 - Disclosure - Financial Instruments - Derivative Financial Instruments and Hedging Activities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/FinancialInstrumentsDerivativeFinancialInstrumentsandHedgingActivitiesDetails</Role>
      <ShortName>Financial Instruments - Derivative Financial Instruments and Hedging Activities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>61</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R62.htm</HtmlFileName>
      <LongName>0000062 - Disclosure - Financial Instruments - Derivative Financial Instruments and Hedging Activities - Footnotes (Details)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.pfizer.com/role/FinancialInstrumentsDerivativeFinancialInstrumentsandHedgingActivitiesFootnotesDetails</Role>
      <ShortName>Financial Instruments - Derivative Financial Instruments and Hedging Activities - Footnotes (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>62</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R63.htm</HtmlFileName>
      <LongName>0000063 - Disclosure - Financial Instruments - Cumulative Basis Adjustments for Fair Value Hedges (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/FinancialInstrumentsCumulativeBasisAdjustmentsforFairValueHedgesDetails</Role>
      <ShortName>Financial Instruments - Cumulative Basis Adjustments for Fair Value Hedges (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>63</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R64.htm</HtmlFileName>
      <LongName>0000064 - Disclosure - Financial Instruments - Credit Risk (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/FinancialInstrumentsCreditRiskDetails</Role>
      <ShortName>Financial Instruments - Credit Risk (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>64</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R65.htm</HtmlFileName>
      <LongName>0000065 - Disclosure - Other Financial Information - Inventories (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/OtherFinancialInformationInventoriesDetails</Role>
      <ShortName>Other Financial Information - Inventories (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>65</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R66.htm</HtmlFileName>
      <LongName>0000066 - Disclosure - Other Financial Information - Other Current Liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/OtherFinancialInformationOtherCurrentLiabilitiesDetails</Role>
      <ShortName>Other Financial Information - Other Current Liabilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>66</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R67.htm</HtmlFileName>
      <LongName>0000067 - Disclosure - Identifiable Intangible Assets - Finite-lived and Indefinite-lived Intangible Assets (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/IdentifiableIntangibleAssetsFinitelivedandIndefinitelivedIntangibleAssetsDetail</Role>
      <ShortName>Identifiable Intangible Assets - Finite-lived and Indefinite-lived Intangible Assets (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>67</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R68.htm</HtmlFileName>
      <LongName>0000068 - Disclosure - Identifiable Intangible Assets - Goodwill (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/IdentifiableIntangibleAssetsGoodwillDetail</Role>
      <ShortName>Identifiable Intangible Assets - Goodwill (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>68</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R69.htm</HtmlFileName>
      <LongName>0000069 - Disclosure - Pension and Postretirement Benefit Plans - Net Periodic Benefit Cost (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/PensionandPostretirementBenefitPlansNetPeriodicBenefitCostDetail</Role>
      <ShortName>Pension and Postretirement Benefit Plans - Net Periodic Benefit Cost (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>69</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R70.htm</HtmlFileName>
      <LongName>0000070 - Disclosure - Pension and Postretirement Benefit Plans - Narrative (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/PensionandPostretirementBenefitPlansNarrativeDetail</Role>
      <ShortName>Pension and Postretirement Benefit Plans - Narrative (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>70</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R71.htm</HtmlFileName>
      <LongName>0000071 - Disclosure - Earnings Per Common Share Attributable to Pfizer Inc. Common Shareholders (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/EarningsPerCommonShareAttributabletoPfizerIncCommonShareholdersDetails</Role>
      <ShortName>Earnings Per Common Share Attributable to Pfizer Inc. Common Shareholders (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.pfizer.com/role/EarningsPerCommonShareAttributabletoPfizerIncCommonShareholdersTables</ParentRole>
      <Position>71</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R72.htm</HtmlFileName>
      <LongName>0000072 - Disclosure - Contingencies and Certain Commitments - Patent Litigation (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/ContingenciesandCertainCommitmentsPatentLitigationDetails</Role>
      <ShortName>Contingencies and Certain Commitments - Patent Litigation (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>72</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R73.htm</HtmlFileName>
      <LongName>0000073 - Disclosure - Contingencies and Certain Commitments - Product Litigation, Commercial and Other Matters, Legal Proceedings (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/ContingenciesandCertainCommitmentsProductLitigationCommercialandOtherMattersLegalProceedingsDetails</Role>
      <ShortName>Contingencies and Certain Commitments - Product Litigation, Commercial and Other Matters, Legal Proceedings (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>73</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R74.htm</HtmlFileName>
      <LongName>0000074 - Disclosure - Segment, Geographic and Other Revenue Information - Narrative (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/SegmentGeographicandOtherRevenueInformationNarrativeDetail</Role>
      <ShortName>Segment, Geographic and Other Revenue Information - Narrative (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.pfizer.com/role/SegmentGeographicandOtherRevenueInformationTables</ParentRole>
      <Position>74</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R75.htm</HtmlFileName>
      <LongName>0000075 - Disclosure - Segment, Geographic and Other Revenue Information - Schedule of Segment Reporting Information by Segment (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/SegmentGeographicandOtherRevenueInformationScheduleofSegmentReportingInformationbySegmentDetails</Role>
      <ShortName>Segment, Geographic and Other Revenue Information - Schedule of Segment Reporting Information by Segment (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>75</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R76.htm</HtmlFileName>
      <LongName>0000076 - Disclosure - Segment, Geographic and Other Revenue Information - Revenues By Geographic Area (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/SegmentGeographicandOtherRevenueInformationRevenuesByGeographicAreaDetail</Role>
      <ShortName>Segment, Geographic and Other Revenue Information - Revenues By Geographic Area (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>76</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R77.htm</HtmlFileName>
      <LongName>0000077 - Disclosure - Segment, Geographic and Other Revenue Information - Revenues By Products (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pfizer.com/role/SegmentGeographicandOtherRevenueInformationRevenuesByProductsDetail</Role>
      <ShortName>Segment, Geographic and Other Revenue Information - Revenues By Products (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>77</Position>
    </Report>
    <Report instance="pfe-20221002.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R78.htm</HtmlFileName>
      <LongName>0000078 - Disclosure - Segment, Geographic and Other Revenue Information - Revenues By Products - Footnotes (Details)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.pfizer.com/role/SegmentGeographicandOtherRevenueInformationRevenuesByProductsFootnotesDetails</Role>
      <ShortName>Segment, Geographic and Other Revenue Information - Revenues By Products - Footnotes (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>78</Position>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <LongName>All Reports</LongName>
      <ReportType>Book</ReportType>
      <ShortName>All Reports</ShortName>
    </Report>
  </MyReports>
  <Logs>
    <Log type="Warning">[ix-0514-Hidden-Fact-Eligible-For-Transform] WARN: 3 fact(s) appearing in ix:hidden were eligible for transformation: us-gaap:RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1 -  pfe-20221002.htm 4</Log>
  </Logs>
  <InputFiles>
    <File doctype="10-Q" original="pfe-20221002.htm">pfe-20221002.htm</File>
    <File>pfe-20221002.xsd</File>
    <File>pfe-20221002_cal.xml</File>
    <File>pfe-20221002_def.xml</File>
    <File>pfe-20221002_lab.xml</File>
    <File>pfe-20221002_pre.xml</File>
    <File>pfe-exh311x1002202210q.htm</File>
    <File>pfe-exh312x1002202210q.htm</File>
    <File>pfe-exh321x1002202210q.htm</File>
    <File>pfe-exh322x1002202210q.htm</File>
  </InputFiles>
  <SupplementalFiles/>
  <BaseTaxonomies>
    <BaseTaxonomy items="1651">http://fasb.org/us-gaap/2022</BaseTaxonomy>
    <BaseTaxonomy items="32">http://xbrl.sec.gov/dei/2022</BaseTaxonomy>
  </BaseTaxonomies>
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
