PENSION AND POSTRETIREMENT BENEFIT PLANS - Obligations and Funded Status of our Defined Benefit Plans (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Amounts recognized in the balance sheet:
Amounts recognized in accumulated other comprehensive (loss) income:	$ (23)	$ (6)
Pension Benefits
Amounts recognized in the balance sheet:
Accrued liabilities	0	0
Other long-term liabilities	(18)	(14)
Amounts recognized in the consolidated balance sheets, total	(18)	(14)
Amounts recognized in accumulated other comprehensive (loss) income:	(6)	(10)
Changes in the benefit obligation:
Benefit obligation—beginning of year	56		$ 65
Service cost—benefits earned during the period	1	1	1
Interest cost on projected benefit obligation	2	2	2
Actuarial loss (gain)	11	(2)
Cost of special termination benefits	0	0	0
Curtailment	0	0
Benefits paid	(25)	(10)
Benefit obligation—end of year	45	56
Changes in plan assets:
Fair value of plan assets—beginning of year	42		46
Actual gain (loss) on plan assets	7	(2)
Employer contributions	3	8
Benefits paid	(25)	(10)
Fair value of plan assets—end of year	27	42
Unfunded status	(18)	(14)
Postretirement Benefits
Amounts recognized in the balance sheet:
Accrued liabilities	(3)	(2)
Other long-term liabilities	(113)	(82)
Amounts recognized in the consolidated balance sheets, total	(116)	(84)
Amounts recognized in accumulated other comprehensive (loss) income:	(17)	4
Changes in the benefit obligation:
Benefit obligation—beginning of year	84		93
Service cost—benefits earned during the period	4	4	3
Interest cost on projected benefit obligation	4	4	4
Actuarial loss (gain)	19	(14)
Cost of special termination benefits	6	0	0
Curtailment	2	0
Benefits paid	(3)	(3)
Benefit obligation—end of year	116	84
Changes in plan assets:
Fair value of plan assets—beginning of year	0		$ 0
Actual gain (loss) on plan assets	0	0
Employer contributions	3	3
Benefits paid	(3)	(3)
Fair value of plan assets—end of year	0	0
Unfunded status	$ (116)	$ (84)