Leased Vehicles - Summary of Leased Vehicles (Details) - USD ($) $ in Millions	Mar. 31, 2016	Dec. 31, 2015
Property Subject to or Available for Operating Lease, Net [Abstract]
Leased vehicles	$ 33,707	$ 27,587
Manufacturer incentives	(5,606)	(4,582)
Leased vehicles accounted for operating leases net of manufacturing incentives	28,101	23,005
Less: accumulated depreciation	(3,563)	(2,833)
Leased vehicles, net	$ 24,538	$ 20,172