Leasing (Schedule of Property Subject to or Available for Operating Lease) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Lessor, Lease, Description [Line Items]
Residual value guarantee	15.00%	15.00%
Vehicles available for operating lease, gross	$ 11,182	$ 10,426
Lessor Operating Lease Accumulated Depreciation	(1,543)	(1,562)
Investment in operating leases, net	$ 9,639	8,864
Minimum
Lessor, Lease, Description [Line Items]
Lessor, operating lease, lessee option to purchase underlying asset	24
Maximum
Lessor, Lease, Description [Line Items]
Lessor, operating lease, lessee option to purchase underlying asset	60
Vehicles
Lessor, Lease, Description [Line Items]
Operating Lease, Residual Value of Leased Asset	$ 352	$ 352