LEASES - Supplemental Cash Flow Information (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Leases [Abstract]
Property and equipment, at cost	$ 170		$ 168
Finance Lease, Right-Of-Use Asset, Accumulated Depreciation	31		$ 25
Operating cash flows related to operating leases	6	$ 7
Financing cash flows related to finance leases	$ 5	$ 4
Weighted average remaining lease term (in years): operating	11 years 4 months 24 days		11 years 9 months 18 days
Weighted average remaining lease term (in years): finance	31 years 3 months 18 days		33 years 4 months 24 days
Weighted average discount rate: operating	4.58%		4.65%
Weighted average discount rate: finance	5.06%		5.06%
Operating Lease, Liability, Noncurrent	$ 44		$ 46
Operating Lease, Liability	$ 50		$ 52