Guarantor Consolidating Financial Statements - Current Period Guarantor Balance Sheet (Details) - USD ($) $ in Millions	Dec. 31, 2015	Jan. 02, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Condensed Balance Sheet Statements, Captions [Line Items]
Cash and cash equivalents	$ 3,061		$ 2,974	$ 1,074	$ 1,289
Finance receivables, net	36,781		33,000
Leased vehicles, net	20,172		7,060	3,400
Restricted cash	1,941		2,071
Goodwill	1,189	$ 371	1,244	1,240	1,108
Equity in net assets of non-consolidated affiliates (Note 7)	986		0
Property and equipment, net	219		172
Deferred income taxes	231		341
Related party receivables	573		384
Other assets	751		362
Due from affiliates	0		0
Equity in net assets of non-consolidated affiliates	0		0
Total assets	65,904		47,608
Secured debt	30,689		25,173
Unsecured debt	23,657		12,142
Accounts payable and accrued expenses	1,218		1,002
Deferred income	1,454		392
Deferred income taxes	129		20
Related party taxes payable	0		636
Related party payables	362		433
Other liabilities	343		418
Due to affiliates	0		0
Total liabilities	57,852		40,216
Common stock	0		0
Additional paid-in capital	6,484		5,799
Accumulated other comprehensive loss	(1,104)		(433)	11
Retained earnings	2,672		2,026
Total shareholder's equity	8,052		7,392
Total liabilities and shareholder's equity	65,904		47,608
Parent Company [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Cash and cash equivalents	0		0	0	0
Finance receivables, net	0		0
Leased vehicles, net	0		0
Restricted cash	0		0
Goodwill	1,095		1,095
Equity in net assets of non-consolidated affiliates (Note 7)	0
Property and equipment, net	0		0
Deferred income taxes	212		28
Related party receivables	0		0
Other assets	32		29
Due from affiliates	15,573		6,787
Equity in net assets of non-consolidated affiliates	8,476		7,684
Total assets	25,388		15,623
Secured debt	0		0
Unsecured debt	17,087		7,435
Accounts payable and accrued expenses	181		78
Deferred income	0		0
Deferred income taxes	0		0
Related party taxes payable			636
Related party payables	0		0
Other liabilities	68		82
Due to affiliates	0		0
Total liabilities	17,336		8,231
Common stock	0		0
Additional paid-in capital	6,484		5,799
Accumulated other comprehensive loss	(1,104)		(433)
Retained earnings	2,672		2,026
Total shareholder's equity	8,052		7,392
Total liabilities and shareholder's equity	25,388		15,623
Guarantor Subsidiaries [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Cash and cash equivalents	2,259		2,266	395	1,252
Finance receivables, net	4,808		2,401
Leased vehicles, net	0		0
Restricted cash	60		17
Goodwill	0		0
Equity in net assets of non-consolidated affiliates (Note 7)	0
Property and equipment, net	41		23
Deferred income taxes	0		0
Related party receivables	27		11
Other assets	32		18
Due from affiliates	7,556		1,965
Equity in net assets of non-consolidated affiliates	6,425		4,059
Total assets	21,208		10,760
Secured debt	0		0
Unsecured debt	0		0
Accounts payable and accrued expenses	717		156
Deferred income	0		0
Deferred income taxes	289		288
Related party taxes payable			0
Related party payables	0		0
Other liabilities	34		12
Due to affiliates	15,495		6,129
Total liabilities	16,535		6,585
Common stock	0		0
Additional paid-in capital	79		79
Accumulated other comprehensive loss	(175)		(64)
Retained earnings	4,769		4,160
Total shareholder's equity	4,673		4,175
Total liabilities and shareholder's equity	21,208		10,760
Non-Guarantor Subsidiaries [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Cash and cash equivalents	802		708	679	37
Finance receivables, net	31,973		30,599
Leased vehicles, net	20,172		7,060
Restricted cash	1,881		2,054
Goodwill	94		149
Equity in net assets of non-consolidated affiliates (Note 7)	986
Property and equipment, net	178		149
Deferred income taxes	179		601
Related party receivables	546		373
Other assets	687		315
Due from affiliates	0		400
Equity in net assets of non-consolidated affiliates	0		0
Total assets	57,498		42,408
Secured debt	30,689		25,173
Unsecured debt	6,570		4,707
Accounts payable and accrued expenses	320		768
Deferred income	1,454		392
Deferred income taxes	0		20
Related party taxes payable			0
Related party payables	362		433
Other liabilities	241		324
Due to affiliates	7,634		3,023
Total liabilities	47,270		34,840
Common stock	698		690
Additional paid-in capital	6,490		4,064
Accumulated other comprehensive loss	(1,095)		(410)
Retained earnings	4,135		3,224
Total shareholder's equity	10,228		7,568
Total liabilities and shareholder's equity	57,498		42,408
Consolidation, Eliminations [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Cash and cash equivalents	0		0	$ 0	$ 0
Finance receivables, net	0		0
Leased vehicles, net	0		0
Restricted cash	0		0
Goodwill	0		0
Equity in net assets of non-consolidated affiliates (Note 7)	0
Property and equipment, net	0		0
Deferred income taxes	(160)		(288)
Related party receivables	0		0
Other assets	0		0
Due from affiliates	(23,129)		(9,152)
Equity in net assets of non-consolidated affiliates	(14,901)		(11,743)
Total assets	(38,190)		(21,183)
Secured debt	0		0
Unsecured debt	0		0
Accounts payable and accrued expenses	0		0
Deferred income	0		0
Deferred income taxes	(160)		(288)
Related party taxes payable			0
Related party payables	0		0
Other liabilities	0		0
Due to affiliates	(23,129)		(9,152)
Total liabilities	(23,289)		(9,440)
Common stock	(698)		(690)
Additional paid-in capital	(6,569)		(4,143)
Accumulated other comprehensive loss	1,270		474
Retained earnings	(8,904)		(7,384)
Total shareholder's equity	(14,901)		(11,743)
Total liabilities and shareholder's equity	$ (38,190)		$ (21,183)