SIGNIFICANT ACCOUNTING POLICIES - Effect of Revisions on the Consolidated Balance Sheet (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018	Dec. 31, 2017
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Deferred tax liabilities, net	$ 880	$ 885	$ 1,027
Total liabilities	29,772	29,677	31,163
Accumulated deficit	(5,716)	(5,664)	(4,097)
Total Bausch Health Companies Inc. shareholders' equity	2,693	2,733	4,536
Total equity	$ 2,779	$ 2,815	4,635	$ 5,944
As Previously Reported
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Deferred tax liabilities, net			1,139
Total liabilities			31,275
Accumulated deficit			(4,209)
Total Bausch Health Companies Inc. shareholders' equity			4,424
Total equity			4,523
Adjustment | Error In Forecasted Effective Tax Rate
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Deferred tax liabilities, net			(112)
Total liabilities			(112)
Accumulated deficit			112
Total Bausch Health Companies Inc. shareholders' equity			112
Total equity			$ 112