LEASES - Lease Maturity (Details) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Leases [Abstract]
Lessee, Operating Lease, Liability, to be Paid, Year One	$ 5
Finance Lease, Liability, to be Paid, Year One	5
Operating Leases
2020	9
2021	8
2022	7
2023	6
2025 and thereafter	33
Total lease payments	68
Less: Amounts representing interest	(16)
Total lease obligations	52	$ 52
Finance Leases
2020	12
2021	12
2022	12
2023	11
2025 and thereafter	105
Total lease payments	157
Less: Amounts representing interest	(69)
Total lease obligations	$ 88	$ 90