Restructuring Charges and Other Costs Associated with Acquisitions and Cost-Reduction/Productivity Initiatives - Footnotes (Detail) - USD ($) $ in Millions		3 Months Ended
		Mar. 29, 2020	Mar. 31, 2019
Restructuring Cost and Reserve [Line Items]
Restructuring charge (credit)	[1]	$ 56	$ 10
Other [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charge (credit)		41	10
Biopharma [Member] | Operating Segments [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charge (credit)		2	13
Upjohn [Member] | Operating Segments [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charge (credit)		$ 13	$ (13)

[1] In the first quarter of 2020, restructuring charges mainly represent asset write-downs and employee termination costs associated with cost reduction initiatives. In the first quarter of 2019, restructuring charges were primarily associated with cost reduction initiatives and mainly represent asset write-downs, partially offset by the reversal of previously recorded accruals for employee termination costs and asset impairments related to our acquisition of Hospira. The restructuring activities for the first quarter of 2020 are associated with the following: • Biopharma ($2 million charge); Upjohn ($13 million charge); and Other ($41 million charge). The restructuring activities for the first quarter of 2019 are associated with the following: • Biopharma ($13 million charge); Upjohn ($13 million credit); and Other ($10 million charge).