INCOME TAXES - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
State operating loss carryforwards	$ 1,100
Deferred tax asset valuation allowance	79	$ 110
Decrease in deferred tax asset valuation allowance	31
Unrecognized tax benefits that would impact effective tax rate	5
Interest on unrecognized tax benefits accrued (released) during period	0	0	$ 8
Accrued interest on unrecognized tax benefits	1	2	1
Penalties accrued income tax examination	0	0	0
Penalties expense income tax examination	0	$ 0	$ 0
Tax Years Ended Prior to 1988
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Base year loan loss reserves attributable to prior years	$ 557