REVENUE REVENUE BY PRODUCT AND REGION (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Revenue from External Customer [Line Items]
Revenues	$ 11,068	$ 10,540	$ 10,129	$ 10,781	$ 7,945	$ 6,007	$ 6,273	$ 5,920	$ 42,518	$ 26,145	$ 22,561
UNITED STATES
Revenue from External Customer [Line Items]
Revenues									26,577	15,342	12,586
European Union [Member]
Revenue from External Customer [Line Items]
Revenues									9,853	6,266	5,658
Rest Of World [Member]
Revenue from External Customer [Line Items]
Revenues									5,457	4,013	3,733
Other Region [Member]
Revenue from External Customer [Line Items]
Revenues									631	524	584
Revlimid [Member]
Revenue from External Customer [Line Items]
Revenues									12,106	1,299	0
Eliquis [Member]
Revenue from External Customer [Line Items]
Revenues									9,168	7,929	6,438
Opdivo [Member]
Revenue from External Customer [Line Items]
Revenues									6,992	7,204	6,735
Orencia [Member]
Revenue from External Customer [Line Items]
Revenues									3,157	2,977	2,710
Pomalyst/Imnovid [Member]
Revenue from External Customer [Line Items]
Revenues									3,070	322	0
Sprycel [Member]
Revenue from External Customer [Line Items]
Revenues									2,140	2,110	2,000
Yervoy [Member]
Revenue from External Customer [Line Items]
Revenues									1,682	1,489	1,330
Abraxane [Member]
Revenue from External Customer [Line Items]
Revenues									1,247	166	0
Empliciti [Member]
Revenue from External Customer [Line Items]
Revenues									381	357	247
Reblozyl
Revenue from External Customer [Line Items]
Revenues									274	0	0
Inrebic [Member]
Revenue from External Customer [Line Items]
Revenues									55	5	0
Onureg
Revenue from External Customer [Line Items]
Revenues									17	0	0
Zeposia
Revenue from External Customer [Line Items]
Revenues									12	0	0
Vidaza [Member]
Revenue from External Customer [Line Items]
Revenues									455	58	0
Baraclude [Member]
Revenue from External Customer [Line Items]
Revenues									447	555	744
Mature Products And All Other [Member]
Revenue from External Customer [Line Items]
Revenues									$ 1,315	$ 1,674	$ 2,357