Other (Income)/Deductions - Net - Schedule of Other (Income)/Deductions - Net (Detail) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jul. 02, 2023	Jul. 03, 2022	Jul. 02, 2023	Jul. 03, 2022
Other Income and Expenses [Abstract]
Interest income		$ (316)	$ (30)	$ (493)	$ (44)
Interest expense		508	293	826	614
Net interest expense	[1]	192	263	333	571
Royalty-related income		(273)	(217)	(477)	(389)
Net (gains)/losses on asset disposals		5	0	(2)	(1)
Net (gains)/losses recognized during the period on equity securities	[2],[3]	(135)	541	316	1,241
Income from collaborations, out-licensing arrangements and sales of compound/product rights		(7)	(5)	(74)	(14)
Net periodic benefit costs/(credits) other than service costs		(88)	295	(168)	12
Certain legal matters, net	[4]	139	19	175	98
Certain asset impairments	[5]	0	0	264	0
Haleon/Consumer Healthcare JV equity method (income)/loss	[6]	(156)	(149)	(224)	(334)
Other, net	[7]	(24)	26	(421)	(62)
Other (income)/deductions––net		$ (347)	$ 772	$ (277)	$ 1,122

[1] The decrease in net interest expense in the second quarter and first six months of 2023 reflects higher interest expense driven by our $31 billion aggregate principal amount of senior unsecured notes issued in May 2023 as part of the financing for our proposed acquisition of Seagen, which was more than offset by higher interest income on the investment of the net proceeds from the debt issuance.

[2] Reported in Other (income)/deductions––net. See Note 4.

[3] The net gains in the second quarter of 2023 include, among other things, unrealized gains of $202 million related to our investment in Cerevel Therapeutics Holdings, Inc. (Cerevel). The net losses in the first six months of 2023 include, among other things, unrealized losses of $276 million related to our investment in BioNTech. The net losses in 2022 included, among other things, unrealized losses of $432 million in the second quarter and $776 million in the first six months related to our investments in BioNTech and Cerevel.

[4] The second quarter and first six months of 2023 primarily include certain product liability and other legal expenses related to products discontinued and/or divested by Pfizer. The second quarter and first six months of 2022 primarily included certain product liability expenses related to products discontinued and/or divested by Pfizer. The first six months of 2022 also included legal obligations related to pre-acquisition commitments.

[5] The first six months of 2023 primarily represents intangible asset impairment charges, including $128 million associated with Other business activities, related to IPR&D and developed technology rights for acquired software assets and reflects unfavorable pivotal trial results and updated commercial forecasts, and $120 million associated with our Biopharma segment resulting from the discontinuation of a study related to an out-licensed IPR&D asset for the treatment of prostate cancer, acquired in our Array BioPharma Inc. acquisition.

[6] See Note 2C.

[7] The first six months of 2023 primarily includes, among other things, dividend income of $211 million from our investment in Nimbus resulting from Takeda Pharmaceutical Company Limited’s acquisition of Nimbus’s oral, selective allosteric tyrosine kinase 2 (TYK2) inhibitor program subsidiary, and $183 million from our investment in ViiV.