CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY - USD ($) $ in Millions	Total	Cumulative Effect, Period of Adoption, Adjustment	Common Shares	Additional Paid-In Capital	Accumulated Deficit	Accumulated Deficit Cumulative Effect, Period of Adoption, Adjustment	Accumulated Other Comprehensive Loss	Bausch Health Companies Inc. Shareholders' Equity	Bausch Health Companies Inc. Shareholders' Equity Cumulative Effect, Period of Adoption, Adjustment	Noncontrolling Interest
Beginning Balance (in shares) at Dec. 31, 2018			349,900,000
Beginning Balance at Dec. 31, 2018	$ 2,815		$ 10,121	$ 413	$ (5,664)		$ (2,137)	$ 2,733		$ 82
Increase (Decrease) in Shareholders' Equity
Common shares issued under share-based compensation plans (in shares)			2,500,000
Common shares issued under share-based compensation plans	3		$ 47	(44)				3
Share-based compensation	77			77				77
Employee withholding taxes related to share-based awards	(40)			(40)				(40)
Noncontrolling interest distributions	(8)									(8)
Net income (loss)	(266)				(272)			(272)		6
Other comprehensive (loss) income	(21)						(19)	(19)		(2)
Ending Balance (in shares) at Sep. 30, 2019			352,400,000
Ending Balance at Sep. 30, 2019	2,560		$ 10,168	406	(5,936)		(2,156)	2,482		78
Beginning Balance (in shares) at Dec. 31, 2018			349,900,000
Beginning Balance at Dec. 31, 2018	$ 2,815		$ 10,121	413	(5,664)		(2,137)	2,733		82
Ending Balance (in shares) at Dec. 31, 2019	352,562,636		352,600,000
Ending Balance at Dec. 31, 2019	$ 1,136	$ (1)	$ 10,172	429	(7,452)	$ (1)	(2,086)	1,063	$ (1)	73
Increase (Decrease) in Shareholders' Equity
Accounting Standards Update [Extensible List]	us-gaap:AccountingStandardsUpdate201613Member
Beginning Balance (in shares) at Jun. 30, 2019			352,200,000
Beginning Balance at Jun. 30, 2019	$ 2,688		$ 10,165	384	(5,887)		(2,061)	2,601		87
Increase (Decrease) in Shareholders' Equity
Common shares issued under share-based compensation plans (in shares)			200,000
Common shares issued under share-based compensation plans	0		$ 3	(3)				0
Share-based compensation	26			26				26
Employee withholding taxes related to share-based awards	(1)			(1)				(1)
Noncontrolling interest distributions	(8)									(8)
Net income (loss)	(48)				(49)			(49)		1
Other comprehensive (loss) income	(97)						(95)	(95)		(2)
Ending Balance (in shares) at Sep. 30, 2019			352,400,000
Ending Balance at Sep. 30, 2019	$ 2,560		$ 10,168	406	(5,936)		(2,156)	2,482		78
Beginning Balance (in shares) at Dec. 31, 2019	352,562,636		352,600,000
Beginning Balance at Dec. 31, 2019	$ 1,136	$ (1)	$ 10,172	429	(7,452)	$ (1)	(2,086)	1,063	$ (1)	73
Increase (Decrease) in Shareholders' Equity
Common shares issued under share-based compensation plans (in shares)			2,400,000
Common shares issued under share-based compensation plans	2		$ 47	(45)				2
Share-based compensation	81			81				81
Employee withholding taxes related to share-based awards	(30)			(30)				(30)
Noncontrolling interest distributions	(6)									(6)
Net income (loss)	(407)				(407)			(407)
Other comprehensive (loss) income	$ (120)						(121)	(121)		1
Ending Balance (in shares) at Sep. 30, 2020	355,026,950		355,000,000.0
Ending Balance at Sep. 30, 2020	$ 655		$ 10,219	435	(7,860)		(2,207)	587		68
Increase (Decrease) in Shareholders' Equity
Accounting Standards Update [Extensible List]	us-gaap:AccountingStandardsUpdate201613Member
Beginning Balance (in shares) at Jun. 30, 2020			354,900,000
Beginning Balance at Jun. 30, 2020	$ 546		$ 10,217	411	(7,931)		(2,223)	474		72
Increase (Decrease) in Shareholders' Equity
Common shares issued under share-based compensation plans (in shares)			100,000
Common shares issued under share-based compensation plans	0		$ 2	(2)				0
Share-based compensation	27			27				27
Employee withholding taxes related to share-based awards	(1)			(1)				(1)
Noncontrolling interest distributions	(6)									(6)
Net income (loss)	70				71			71		(1)
Other comprehensive (loss) income	$ 19						16	16		3
Ending Balance (in shares) at Sep. 30, 2020	355,026,950		355,000,000.0
Ending Balance at Sep. 30, 2020	$ 655		$ 10,219	$ 435	$ (7,860)		$ (2,207)	$ 587		$ 68