LEASES - Lease Maturity (Details) $ in Millions	Mar. 31, 2019 USD ($)
Operating Leases
Remainder of 2019	$ 7
2020	8
2021	8
2022	7
2023	7
2024 and thereafter	44
Total lease payments	81
Less: Amounts representing interest	(21)
Total lease obligations	60
Finance Leases
Remainder of 2019	13
2020	18
2021	18
2022	17
2023	18
2024 and thereafter	149
Total lease payments	233
Less: Amounts representing interest	(82)
Total lease obligations	$ 151