Leases - Lease Costs (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Leases [Abstract]
Operating lease expense	$ 126	$ 122	$ 131
Finance lease expense (amortization of right-of-use assets)	5	2	1
Short-term lease expense	8	6	13
Variable lease expense	6	24	26
Sublease income	(4)	(1)	(1)
Total lease expense	$ 141	$ 153	$ 170
Weighted average remaining lease term, operating leases	6 years 1 month 28 days	5 years 4 months 17 days
Weighted average remaining lease term, finance leases	3 years 4 months 6 days	3 years 11 months 19 days
Weighted average discount rate, operating leases	3.42%	3.63%
Weighted average discount rate, finance leases	2.66%	3.07%