INCOME TAXES Income Taxes - Effective Rate Reconciliation (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Schedule of Effective Income Tax Rate Reconciliation [Line Items]
Computed statutory income tax expense at 35%	$ 33	$ (108)	$ (231)
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount	0	(249)	0
State income taxes, net of federal income tax benefit	14	1	(6)
Non-deductible goodwill impairment	0	92	223
Other	2	1	1
Total income tax expense (benefit)	$ 49	$ (263)	$ (13)