Segment, Geographic and Other Revenue Information - Narrative (Detail) $ in Millions	3 Months Ended	6 Months Ended
	Jun. 29, 2025 USD ($)	Jun. 29, 2025 USD ($) segment	Dec. 31, 2024 USD ($)
Segment Reporting Information [Line Items]
Number of operating segments | segment		3
Number of reportable segments | segment		1
Total assets	$ 206,095	$ 206,095	$ 213,396
Deferred revenues, current	1,123	1,123	1,511
Comirnaty [Member]
Segment Reporting Information [Line Items]
Remaining performance obligation	4,000	4,000
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	1,900	1,900	2,200
Deferred revenues, current	1,000	1,000	1,400
Deferred revenues, noncurrent	906	906	$ 785
Deferred revenue recognized	$ 45	$ 380