SEGMENT INFORMATION - Segment Revenues and Profit, Assets and Capital Expenditures, Depreciation & Amortization of Intangible Assets & Asset Impairments (Details) - USD ($) $ in Millions			3 Months Ended								12 Months Ended
	May 26, 2020	Mar. 08, 2019	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
Segment reporting information
Revenue			$ 2,213	$ 2,138	$ 1,664	$ 2,012	$ 2,224	$ 2,209	$ 2,152	$ 2,016	$ 8,027	$ 8,601	$ 8,380
Operating income (loss)			$ (5)	$ 460	$ (27)	$ 248	$ (1,076)	$ 329	$ 257	$ 287	676	(203)	(2,384)
Amortization of intangible assets											(1,645)	(1,897)	(2,644)
Goodwill impairments											0	0	(2,322)
Asset impairments, including loss on assets held for sale											(114)	(75)	(568)
Restructuring, integration and separation costs											(22)	(31)	(22)
Acquisition-related contingent consideration											(48)	(12)	9
Other (expense) income, net											(454)	(1,414)	20
Interest income											13	12	11
Interest expense											(1,534)	(1,612)	(1,685)
Loss on extinguishment of debt	$ (27)	$ (8)									(59)	(42)	(119)
Foreign exchange and other											(30)	8	23
Loss before benefit from income taxes											(934)	(1,837)	(4,154)
Capital expenditures:
Total capital expenditures											302	270	157
Bausch + Lomb/International
Segment reporting information
Revenue											4,408	4,739	4,664
Salix
Segment reporting information
Revenue											1,904	2,022	1,749
Ortho Dermatologics
Segment reporting information
Revenue											553	565	617
Diversified Products
Segment reporting information
Revenue											1,162	1,275	1,350
Operating Segments
Segment reporting information
Revenue											8,027	8,601	8,380
Operating income (loss)											3,578	3,835	3,748
Capital expenditures:
Total capital expenditures											289	230	144
Operating Segments | Bausch + Lomb/International
Segment reporting information
Revenue											4,408	4,739	4,664
Operating income (loss)											1,159	1,332	1,330
Capital expenditures:
Total capital expenditures											282	225	139
Operating Segments | Salix
Segment reporting information
Revenue											1,904	2,022	1,749
Operating income (loss)											1,338	1,349	1,149
Capital expenditures:
Total capital expenditures											3	2	2
Operating Segments | Ortho Dermatologics
Segment reporting information
Revenue											553	565	617
Operating income (loss)											233	222	257
Capital expenditures:
Total capital expenditures											2	1	1
Operating Segments | Diversified Products
Segment reporting information
Revenue											1,162	1,275	1,350
Operating income (loss)											848	932	1,012
Capital expenditures:
Total capital expenditures											2	2	2
Corporate
Segment reporting information
Operating income (loss)											(619)	(609)	(605)
Capital expenditures:
Total capital expenditures											$ 13	$ 40	$ 13