Leases - Undiscounted Cash Flows under ASC 842 (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Operating Leases
2022	$ 16	$ 19
2023	9	14
2024	7	9
2025	2	5
2026	1	3
Thereafter	0	1
Total minimum lease payments	35	51
Less: amount of lease payments representing interest	(5)	(8)
Present value of future minimum lease payments	30	43
Less: current obligations under leases	(12)	(15)
Long-term lease obligations	18	28
Finance Lease, Liability, Payment, Due [Abstract]
2022	80	80
2023	44	56
2024	11	17
2025	0	0
2026	0	0
Thereafter	0	0
Total minimum lease payments	135	153
Less: amount of lease payments representing interest	(5)	(8)
Present value of future minimum lease payments	130	145
Less: current obligations under leases	(77)	(75)
Long-term lease obligations	$ 53	$ 70