Leases - Other Information Associated With Leases (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$ 200	$ 200	$ 194
Operating cash flows from finance leases	20	20	20
Financing cash flows from finance leases	31	29	26
Supplemental noncash information on lease liabilities arising from obtaining right-of-use assets:
Right-of-use assets obtained in exchange for new finance lease obligations	52	59	18
Right-of-use assets obtained in exchange for new operating lease obligations	$ 133	$ 118	$ 163