Leases - Supplemental Cash Flows (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Leases [Abstract]
Operating cash flows from operating leases (less than $1 million)	$ 0	$ 0
Operating cash flows from finance leases	(3)	(3)
Financing cash flows from finance leases	$ (1)	$ (1)	$ (1)
Weighted-average remaining lease term - operating leases	18 years	19 years	20 years
Weighted-average remaining lease term - finance leases	9 years	10 years	11 years
Weighted-average discount rate - operating leases	5.30%	5.80%	5.80%
Weighted-average discount rate - finance leases	14.30%	14.30%	14.30%