Leasing (Depreciation Expense on Operating Lease Assets) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Leases [Abstract]
Operating lease revenue	$ 392	$ 396	$ 794	$ 799
Depreciation expense on operating lease assets (excluding remarketing gains)	270	269	543	536
Remarketing gains, net	(70)	(50)	(117)	(100)
Net depreciation expense on operating lease assets	200	219	426	436
Variable lease payments, excessive wear and tear	$ 2	$ 2	$ 4	$ 4