LEASES - Lease Cost (Details) $ in Millions	12 Months Ended
	Dec. 31, 2019 USD ($)
Leases [Abstract]
Amortization of assets, included in Depreciation and amortization expense	$ 7
Interest on lease liabilities, included in Interest expense	4
Amortization of assets, included in Total operating expense	8
Interest on lease liabilities, included in Total operating expense	2
Total net lease cost	$ 21