Consolidated Statement of Income - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Financing Revenue and Other Interest Income [Abstract]
Interest and fees on finance receivables and loans	$ 1,265	$ 1,118	$ 2,500	$ 2,192
Interest on loans held-for-sale	0	14	0	38
Interest and dividends on investment securities	99	93	201	181
Interest on cash and cash equivalents	4	2	7	4
Operating leases	701	860	1,470	1,756
Total financing revenue and other interest income	2,069	2,087	4,178	4,171
Interest Expense [Abstract]
Interest on deposits	203	177	396	349
Interest on short-term borrowings	12	12	25	23
Interest on long-term debt	436	419	878	848
Total interest expense	651	608	1,299	1,220
Depreciation expense on operating lease assets	434	563	944	1,185
Net financing revenue (loss)	984	916	1,935	1,766
Other revenue [Abstract]
Servicing fees	18	10	31	20
Insurance premiums and service revenue earned	236	237	466	470
Gain (loss) on mortgage and automotive loans, net	3	1	4	47
Loss on extinguishment of debt	0	(156)	(4)	(354)
Other gain on investments, net	39	45	93	100
Other income, net of losses	96	84	191	191
Total other revenue	374	211	750	454
Total net revenue (loss)	1,358	1,127	2,685	2,220
Provision for loan losses	172	140	392	256
Noninterest Expense [Abstract]
Compensation and benefits expense	242	236	494	491
Insurance losses and loss adjustment expenses	145	122	218	178
Other operating expenses	386	366	771	750
Total noninterest expense	773	724	1,483	1,419
Income (loss) from continuing operations before income tax expense	413	263	810	545
Income tax expense (benefit) from continuing operations	56	94	206	197
Net income (loss) from continuing operations	357	169	604	348
Income (loss) from discontinued operations, net of tax	3	13	6	410
Net income (loss)	360	182	610	758
Other Comprehensive Income (Loss), Net of Tax	120	(148)	266	(117)
Comprehensive income	$ 480	$ 34	$ 876	$ 641
Earnings Per Share, Basic [Abstract]
Net income from continuing operations	$ 0.70	$ (2.24)	$ 1.18	$ (2.01)
Income from discontinued operations, net of tax	0.01	0.03	0.01	0.85
Net income	0.71	(2.22)	1.20	(1.16)
Earnings Per Share, Diluted [Abstract]
Net income from continuing operations	0.70	(2.24)	1.18	(2.01)
Income from discontinued operations, net of tax	0.01	0.03	0.01	0.85
Net income	$ 0.71	$ (2.22)	$ 1.19	$ (1.16)