Leases - Other Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Leases [Abstract]
Operating cash flows for operating leases	$ 999	$ 1,053	$ 1,166
Operating cash flows for finance leases	46	32	27
Financing cash flows for finance leases	$ 336	$ 255	$ 192