SEGMENT INFORMATION - Revenues by Product Category (Details) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2020 USD ($)	Sep. 30, 2020 USD ($)	Jun. 30, 2020 USD ($)	Mar. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Sep. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2020 USD ($) product	Dec. 31, 2019 USD ($) product	Dec. 31, 2018 USD ($) product
Revenue from External Customer [Line Items]
Number of products represented of total revenue | product									10	10	10
Revenue	$ 2,213	$ 2,138	$ 1,664	$ 2,012	$ 2,224	$ 2,209	$ 2,152	$ 2,016	$ 8,027	$ 8,601	$ 8,380
Pharmaceuticals
Revenue from External Customer [Line Items]
Revenue									3,678	4,072	4,028
Devices
Revenue from External Customer [Line Items]
Revenue									1,566	1,717	1,640
OTC
Revenue from External Customer [Line Items]
Revenue									1,432	1,452	1,412
Branded and Other Generics
Revenue from External Customer [Line Items]
Revenue									1,248	1,248	1,191
Other revenues
Revenue from External Customer [Line Items]
Revenue									103	112	109
Bausch + Lomb/International
Revenue from External Customer [Line Items]
Revenue									4,408	4,739	4,664
Bausch + Lomb/International | Pharmaceuticals
Revenue from External Customer [Line Items]
Revenue									759	885	892
Bausch + Lomb/International | Devices
Revenue from External Customer [Line Items]
Revenue									1,313	1,524	1,505
Bausch + Lomb/International | OTC
Revenue from External Customer [Line Items]
Revenue									1,432	1,452	1,412
Bausch + Lomb/International | Branded and Other Generics
Revenue from External Customer [Line Items]
Revenue									838	801	784
Bausch + Lomb/International | Other revenues
Revenue from External Customer [Line Items]
Revenue									66	77	71
Salix
Revenue from External Customer [Line Items]
Revenue									1,904	2,022	1,749
Salix | Pharmaceuticals
Revenue from External Customer [Line Items]
Revenue									1,899	2,022	1,752
Salix | Devices
Revenue from External Customer [Line Items]
Revenue									0	0	0
Salix | OTC
Revenue from External Customer [Line Items]
Revenue									0	0	0
Salix | Branded and Other Generics
Revenue from External Customer [Line Items]
Revenue									0	0	0
Salix | Other revenues
Revenue from External Customer [Line Items]
Revenue									5	0	(3)
Ortho Dermatologics
Revenue from External Customer [Line Items]
Revenue									553	565	617
Ortho Dermatologics | Pharmaceuticals
Revenue from External Customer [Line Items]
Revenue									279	355	457
Ortho Dermatologics | Devices
Revenue from External Customer [Line Items]
Revenue									253	193	135
Ortho Dermatologics | OTC
Revenue from External Customer [Line Items]
Revenue									0	0	0
Ortho Dermatologics | Branded and Other Generics
Revenue from External Customer [Line Items]
Revenue									0	0	0
Ortho Dermatologics | Other revenues
Revenue from External Customer [Line Items]
Revenue									21	17	25
Diversified Products
Revenue from External Customer [Line Items]
Revenue									1,162	1,275	1,350
Diversified Products | Pharmaceuticals
Revenue from External Customer [Line Items]
Revenue									741	810	927
Diversified Products | Devices
Revenue from External Customer [Line Items]
Revenue									0	0	0
Diversified Products | OTC
Revenue from External Customer [Line Items]
Revenue									0	0	0
Diversified Products | Branded and Other Generics
Revenue from External Customer [Line Items]
Revenue									410	447	407
Diversified Products | Other revenues
Revenue from External Customer [Line Items]
Revenue									$ 11	$ 18	$ 16
Revenues | Product Concentration Risk
Revenue from External Customer [Line Items]
Concentration risk, percentage									41.00%	39.00%	36.00%