Segment, Geographic and Other Revenue Information (Detail) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 27, 2020	Sep. 29, 2019	Sep. 27, 2020	Sep. 29, 2019
Segment Reporting Information [Line Items]
Revenues		$ 12,131	$ 12,680	$ 35,961	$ 39,062
Earnings	[1]	2,176	10,727	10,014	19,190
Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues		12,131	12,303	35,961	36,964
Earnings	[1]	7,816	7,890	23,554	24,096
Segment Reconciling Items [Member]
Segment Reporting Information [Line Items]
Revenues		0	377	0	2,098
Earnings	[1]	(1,939)	(1,469)	(4,958)	(3,776)
Segment Reconciling Items [Member] | Purchase Accounting Adjustments [Member]
Segment Reporting Information [Line Items]
Revenues		0	0	0	0
Earnings	[1]	(823)	(1,141)	(2,545)	(3,357)
Segment Reconciling Items [Member] | Acquisition-Related Costs [Member]
Segment Reporting Information [Line Items]
Revenues		0	0	0	0
Earnings	[1]	(11)	(300)	(46)	(152)
Segment Reconciling Items [Member] | Certain Significant Items [Member]
Segment Reporting Information [Line Items]
Revenues	[2]	0	0	0	0
Earnings	[1],[2]	(1,675)	7,187	(2,554)	6,495
Corporate and other unallocated [Member]
Segment Reporting Information [Line Items]
Revenues		0	0	0	0
Earnings	[1]	(1,192)	(1,439)	(3,437)	(4,116)
Biopharma [Member]
Segment Reporting Information [Line Items]
Revenues		10,215	9,952	30,017	28,429
Biopharma [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues		10,215	9,952	30,017	28,429
Earnings	[1]	6,807	6,506	20,186	18,461
Upjohn [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues		1,916	2,351	5,944	8,535
Earnings	[1]	$ 1,009	$ 1,384	$ 3,367	$ 5,635

[1] Income from continuing operations before provision/(benefit) for taxes on income. Biopharma’s earnings include dividend income of $44 million in the third quarter of 2020 and $43 million in the third quarter of 2019, and $196 million in the first nine months of 2020 and $184 million in the first nine months of 2019 from our investment in ViiV. See Note 4.

[2] Certain significant items are substantive and/or unusual, and in some cases recurring, items (as noted above) that, either as a result of their nature or size, would not be expected to occur as part of our normal business on a regular basis. In the third quarter and first nine months of 2020, includes, among other items, intangible asset impairment charges of $900 million, recorded in Other (income)/deductions—net, related to IPR&D assets acquired in connection with our Array acquisition. In the third quarter and first nine months of 2019, includes, among other items, a pre-tax gain of $8.1 billion recorded in (Gain) on completion of Consumer Healthcare JV transaction associated with the completion of the GSK Consumer Healthcare joint venture transaction (See Note 2). Certain significant items are discussed further in Note 3 and Note 4.