Acquisition and Equity-Method Investment - Pro Forma Information (Details) - Seagen [Member] - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	9 Months Ended
Oct. 01, 2023	Oct. 01, 2023
Business Acquisition [Line Items]
Revenues	$ 14,140	$ 46,756
Net income/(loss) attributable to Pfizer Inc. common shareholders	$ (3,338)	$ 2,702
Diluted earnings/(loss) per share attributable to Pfizer Inc. common shareholders	$ (0.59)	$ 0.47

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 805
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (a)
-Publisher FASB
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+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (h)(2)
-SubTopic 10
-Topic 805
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479328/805-10-50-2

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 805
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (h)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479328/805-10-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-URI https://asc.fasb.org/1943274/2147479328/805-10-50-2

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