ACQUISITIONS, DIVESTITURES, LICENSING AND OTHER ARRANGEMENTS - Licensing and Other Arrangements (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Royalty income, nonoperating	$ (45)	$ (23)	$ (11)
Up-front licensing fees	(34)	(30)	(29)
Contingent milestone income	(18)	(72)	(31)
Amortization of deferred income	(39)	(58)	(58)
Licensing and other arrangements income	(1,067)	(883)	(674)
Keytruda royalties
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Royalty income, nonoperating	(841)	(681)	(545)
Tecentriq royalties
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Royalty income, nonoperating	$ (90)	$ (19)	$ 0