| **Contingencies and Certain Commitments - Patent Litigation (Details) $ in Millions**                                                                                                      | 1 Months Ended |        |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|----------------|--------|
||
| **Gain Contingencies [Line Items]**                                                                                                                                                        |           |   |   |   |   |   |   |   |   |
| Threshold for disclosure of proceedings under environmental laws | $                                                                                                                       |           |   |   |   |   |   |   |   | $ 1 |
| Loss contingency, patents allegedly infringed and subsequently revoked | Patent                                                                                                            | 1              |   |   |   |   |   |   |   |   |
| Mektovi [Member] | Pfizer Versus Several Generic Manufacturers [Member] | Patent Infringement [Member] | Pending Litigation [Member]                                                       |           |   |   |   |   |   |   |   |   |
| **Gain Contingencies [Line Items]**                                                                                                                                                        |           |   |   |   |   |   |   |   |   |
| Number of patents allegedly infringed upon                                                                                                                                                 |           |   |   |   |   | 6 |   |   |   |
| Mektovi [Member] | Pfizer Versus Several Generic Manufacturers [Member] | Patent Infringement [Member] | Pending Litigation [Member] | Expiring 2030 [Member]                              |           |   |   |   |   |   |   |   |   |
| **Gain Contingencies [Line Items]**                                                                                                                                                        |           |   |   |   |   |   |   |   |   |
| Number of patents allegedly infringed upon                                                                                                                                                 |           |   |   |   |   |   | 2 |   |   |
| Mektovi [Member] | Pfizer Versus Several Generic Manufacturers [Member] | Patent Infringement [Member] | Pending Litigation [Member] | Expiring 2033 [Member]                              |           |   |   |   |   |   |   |   |   |
| **Gain Contingencies [Line Items]**                                                                                                                                                        |           |   |   |   |   |   |   |   |   |
| Number of patents allegedly infringed upon                                                                                                                                                 |           |   |   |   |   |   | 2 |   |   |
| Mektovi [Member] | Pfizer Versus Teva Pharmaceuticals, Inc. [Member] | Patent Invalidity And Non Infringement [Member] | Pending Litigation [Member]                                       |           |   |   |   |   |   |   |   |   |
| **Gain Contingencies [Line Items]**                                                                                                                                                        |           |   |   |   |   |   |   |   |   |
| Number of patents allegedly infringed upon                                                                                                                                                 |           |   | 3 |   |   |   |   |   |   |
| Mektovi [Member] | Pfizer Versus Teva Pharmaceuticals, Inc. [Member] | Patent Invalidity And Non Infringement [Member] | Pending Litigation [Member] | Teva Pharmaceuticals, Inc. [Member] |           |   |   |   |   |   |   |   |   |
| **Gain Contingencies [Line Items]**                                                                                                                                                        |           |   |   |   |   |   |   |   |   |
| Number of patents allegedly infringed upon                                                                                                                                                 |           |   |   |   |   |   | 2 |   |   |
| Comirnaty [Member] | ModernaTX U.S. Patent Infringement Case [Member]                                                                                                                      |           |   |   |   |   |   |   |   |   |
| **Gain Contingencies [Line Items]**                                                                                                                                                        |           |   |   |   |   |   |   |   |   |
| Number of patents allegedly infringed                                                                                                                                                      |           |   |   |   |   |   | 3 |   |   |
| Comirnaty [Member] | Alnylam Patent Infringement Case [Member]                                                                                                                             |           |   |   |   |   |   |   |   |   |
| **Gain Contingencies [Line Items]**                                                                                                                                                        |           |   |   |   |   |   |   |   |   |
| Number of patents allegedly infringed | Patent                                                                                                                                             |           |   |   | 4 |   |   |   |   |   |
| Comirnaty [Member] | ModernaTX European Patent Infringement Case [Member]                                                                                                                  |           |   |   |   |   |   |   |   |   |
| **Gain Contingencies [Line Items]**                                                                                                                                                        |           |   |   |   |   |   |   |   |   |
| Number of patents allegedly infringed                                                                                                                                                      |           |   |   |   |   | 2 | 2 |   |   |
| Comirnaty [Member] | Arbutus and Genevant U.S. Patent Infringement Case [Member]                                                                                                           |           |   |   |   |   |   |   |   |   |
| **Gain Contingencies [Line Items]**                                                                                                                                                        |           |   |   |   |   |   |   |   |   |
| Number of patents allegedly infringed                                                                                                                                                      |           |   |   |   | 5 |   |   |   |   |
| Comirnaty [Member] | Pfizer, BioNTech and BioNTech Manufacturing GmbH Versus CureVac, Judgment of Non-Infringement [Member]                                                                |           |   |   |   |   |   |   |   |   |
| **Gain Contingencies [Line Items]**                                                                                                                                                        |           |   |   |   |   |   |   |   |   |
| Number of patents found not infringed                                                                                                                                                      |           |   |   |   |   |   |   | 3 |   |
| Number of patents found infringed                                                                                                                                                          |           |   |   | 3 |   |   |   |   |   |
| Abrysvo [Member] | GlaxoSmithKline Biologics SA and GlaxoSmithKline LLC US Patent Infringement Case [Member]                                                                               |           |   |   |   |   |   |   |   |   |
| **Gain Contingencies [Line Items]**                                                                                                                                                        |           |   |   |   |   |   |   |   |   |
| Number of patents allegedly infringed                                                                                                                                                      | 2              | 4      |   |   |   |   |   |   |   |

| X                                                                                                                                                                                                                                                                                                                                   |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Loss Contingency, Patents Allegedly Infringed And Subsequently Revoked, Number
+ References
No definition available.
+ Details**Name:**pfe_LossContingencyPatentsAllegedlyInfringedAndSubsequentlyRevokedNumber**Namespace Prefix:**pfe_**Data Type:**xbrli:integerItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                          |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Site Contingency, Regulatory Proceedings, Disclosure Threshold
+ References
No definition available.
+ Details**Name:**pfe_SiteContingencyRegulatoryProceedingsDisclosureThreshold**Namespace Prefix:**pfe_**Data Type:**xbrli:monetaryItemType**Balance Type:**credit**Period Type:**instant |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.
+ References
Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 450 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org//1943274/2147483049/450-30-50-1
+ Details**Name:**us-gaap_GainContingenciesLineItems**Namespace Prefix:**us-gaap_**Data Type:**xbrli:stringItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Number of entity's patents that another entity has allegedly infringed.
+ References
Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 450 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org//1943274/2147483049/450-30-50-1
+ Details**Name:**us-gaap_GainContingencyPatentsAllegedlyInfringedUponNumber**Namespace Prefix:**us-gaap_**Data Type:**xbrli:integerItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Number of another entity's patents that the entity has allegedly infringed.
+ References
Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 450 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483076/450-20-50-4Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 450 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 9 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483076/450-20-50-9
+ Details**Name:**us-gaap_LossContingencyPatentsAllegedlyInfringedNumber**Namespace Prefix:**us-gaap_**Data Type:**xbrli:integerItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Number of another entity's patents that the entity was found to have infringed.
+ References
Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 450 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483076/450-20-50-4Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 450 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 9 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483076/450-20-50-9
+ Details**Name:**us-gaap_LossContingencyPatentsFoundInfringedNumber**Namespace Prefix:**us-gaap_**Data Type:**xbrli:integerItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Number of another entity's patents that the entity was found not to have infringed.
+ References
Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 450 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483076/450-20-50-4Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 450 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 9 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483076/450-20-50-9
+ Details**Name:**us-gaap_LossContingencyPatentsFoundNotInfringedNumber**Namespace Prefix:**us-gaap_**Data Type:**xbrli:integerItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                  |
|------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**srt_ProductOrServiceAxis=pfe_MektoviMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |
| X                                                                                                                                                                   |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**srt_LitigationCaseAxis=pfe_PfizerAndVersusSeveralGenericManufacturersMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |
| X                                                                                                                                                          |
|------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**us-gaap_GainContingenciesByNatureAxis=pfe_PatentInfringementMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |
| X                                                                                                                                                    |
|------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**us-gaap_LitigationStatusAxis=us-gaap_PendingLitigationMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |
| X                                                                                                                                       |
|-----------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**pfe_ExpirationPeriodAxis=pfe_Expiring2030Member**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |
| X                                                                                                                                       |
|-----------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**pfe_ExpirationPeriodAxis=pfe_Expiring2033Member**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |
| X                                                                                                                                                           |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**srt_LitigationCaseAxis=pfe_PfizerVersusTevaPharmaceuticalsIncMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |
| X                                                                                                                                                                          |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**us-gaap_GainContingenciesByNatureAxis=pfe_PatentInvalidityAndNonInfringementMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |
| X                                                                                                                                            |
|----------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**dei_LegalEntityAxis=pfe_TevaPharmaceuticalsIncMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |
| X                                                                                                                                    |
|--------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**srt_ProductOrServiceAxis=pfe_ComirnatyMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |
| X                                                                                                                                                          |
|------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**srt_LitigationCaseAxis=pfe_ModernaTXUSPatentInfringementCaseMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |
| X                                                                                                                                                      |
|--------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**srt_LitigationCaseAxis=pfe_AlnylamPatentInfringementCaseMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |
| X                                                                                                                                                                |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**srt_LitigationCaseAxis=pfe_ModernaTXEuropeanPatentInfringementCaseMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |
| X                                                                                                                                                                   |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**srt_LitigationCaseAxis=pfe_ArbutusAndGenevantUSPatentInfringementCaseMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |
| X                                                                                                                                                                                                         |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**srt_LitigationCaseAxis=pfe_PfizerBioNTechAndBioNTechManufacturingGmbHVersusCureVacJudgmentOfNonInfringementMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |
| X                                                                                                                                  |
|------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**srt_ProductOrServiceAxis=pfe_AbrysvoMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |
| X                                                                                                                                                                                                |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**srt_LitigationCaseAxis=pfe_GlaxoSmithKlineBiologicsSAAndGlaxoSmithKlineLLCUSPatentInfringementCaseMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |