Segment, Geographic and Other Revenue Information - Narrative (Detail) $ in Millions	3 Months Ended	9 Months Ended
Sep. 28, 2025 USD ($)	Sep. 28, 2025 USD ($) segment	Dec. 31, 2024 USD ($)
Segment Reporting Information [Line Items]
Number of operating segments \| segment		3
Number of reportable segments \| segment		1
Total assets	$ 208,731	$ 208,731	$ 213,396
Deferred revenues, current	924	924	1,511
Comirnaty [Member]
Segment Reporting Information [Line Items]
Remaining performance obligation	3,000	3,000
Paxlovid [Member]
Segment Reporting Information [Line Items]
Remaining performance obligation	1,000	1,000
Government and Government Sponsored [Member] \| Paxlovid and Comirnaty [Member]
Segment Reporting Information [Line Items]
Deferred revenues	1,800	1,800	2,200
Deferred revenues, current	790	790	1,400
Deferred revenues, noncurrent	1,000	1,000	$ 785
Deferred revenue recognized	$ 96	$ 476

Amount of asset recognized for present right to economic benefit.

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