Leases - Operating Leases as Lessee (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Lessee, Lease, Description
Options to extend the lease term	true
Options to terminate the lease early	true
Lease, Cost
Operating lease cost	$ 359	$ 329	$ 314
Cash paid for amounts included in the measurement of operating lease liabilities	287	264	253
ROU assets arising from entering into new operating lease obligations	$ 343	$ 396	$ 310
Weighted average remaining lease term at December 31 (in years)	8 years	8 years	8 years
Weighted average discount rate at December 31	2.70%	3.20%	3.90%
Minimum
Lessee, Lease, Description
Operating lease contract term	1 year
Maximum
Lessee, Lease, Description
Operating lease contract term	10 years
Operating lease renewal term	10 years