Consolidated Statement of Income (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012		Dec. 31, 2011		Dec. 31, 2010
Financing Revenue and Other Interest Income [Abstract]
Interest and fees on finance receivables and loans									$ 4,603		$ 4,409		$ 4,475
Interest on loans held-for-sale									155		332		587
Interest on trading assets									13		19		15
Interest and dividends on available-for-sale investment securities									292		351		323
Interest-bearing cash									26		21		34
Operating leases									2,379		1,929		2,583
Total financing revenue and other interest income									7,468		7,061		8,017
Interest Expense [Abstract]
Interest on deposits									644		614		579
Interest on short-term borrowings									90		116		141
Interest on long-term debt									3,466		4,309		4,740
Total interest expense									4,200		5,039		5,460
Depreciation expense on operating lease assets									1,399		941		1,251
Net financing revenue (loss)	611	473	443	342	286	247	341	207	1,869		1,081		1,306
Other revenue [Abstract]
Servicing fees									701		1,358		1,488
Servicing asset valuation and hedge activities, net									(8)		(789)		(394)
Total servicing income, net									693		569		1,094
Insurance premiums and service revenue earned									1,059		1,170		1,371
Gain (loss) on mortgage and automotive loans, net									532		470		1,239
Gain (loss) on extinguishment of debt									(148)		(64)		(124)
Other gain (loss) on investments, net									146		259		502
Other income, net of losses									747		493		334
Total other revenue	481	774	762	1,012	812	385	873	827	3,029		2,897		4,416
Total net revenue (loss)	1,092	1,247	1,205	1,354	1,098	632	1,214	1,034	4,898		3,978		5,722
Provision for loan losses	92	105	34	98	(13)	57	59	85	329		188		357
Noninterest Expense [Abstract]
Compensation and benefits expense									1,365		1,322		1,348
Insurance losses and loss adjustment expenses									461		483		547
Other operating expenses									3,498		2,936		3,078
Total noninterest expense	1,037	877	2,290	1,120	1,420	983	1,277	1,061	5,324		4,741		4,973
Income (loss) from continuing operations before income tax expense	(37)	265	(1,119)	136	(309)	(408)	(122)	(112)	(755)		(951)		392
Income tax expense (benefit) from continuing operations	(1,337)	43	(8)	18	10	13	9	19	(1,284)		51		104
Net income (loss) from continuing operations	1,300	222	(1,111)	118	(319)	(421)	(131)	(131)	529		(1,002)		288
Income (loss) from discontinued operations, net of tax	100	162	213	192	113	211	244	277	667		845		741
Net income (loss)	1,400	384	(898)	310	(206)	(210)	113	146	1,196		(157)		1,029
Net income (loss) attributable to common shareholders [Abstract]
Net income (loss) from continuing operations	1,300	222	(1,111)	118	(319)	(421)	(131)	(131)	529		(1,002)		288
Preferred stock dividends - U.S. Department of Treasury									(535)		(534)		(963)
Preferred stock dividends									(267)		(260)		(282)
Impact of preferred stock amendment									0	[1]	32	[1]	(616)	[1]
Net income (loss) from continuing operations attributable to common shareholders									(273)		(1,764)		(1,573)
Income (loss) from discontinued operations, net of tax	100	162	213	192	113	211	244	277	667		845		741
Net income (loss) attributable to common shareholders									$ 394		$ (919)		$ (832)
Basic weighted-average common shares outstanding									1,330,970		1,330,970		800,597
Diluted weighted-average common shares outstanding									1,330,970	[2]	1,330,970	[2]	800,597	[2]
Earnings Per Share, Basic [Abstract]
Net income (loss) from continuing operations, Per Basic Share	$ 825	$ 16	$ (985)	$ (62)					$ (205)		$ (1,326)		$ (1,965)
Income (Loss) from Discontinued Operations, Net of Tax, Per Basic Share									$ 501		$ 635		$ 926
Net (loss) income, Basic	$ 901	$ 137	$ (825)	$ 82					$ 296		$ (691)		$ (1,039)
Earnings Per Share, Diluted [Abstract]
Net income (loss) from continuing operations, Per Diluted Share	$ 647	$ 16	$ (985)	$ (62)					$ (205)	[2]	$ (1,326)	[2]	$ (1,965)	[2]
Income (loss) from discontinued operations, net of tax									$ 501	[2]	$ 635	[2]	$ 926	[2]
Net (loss) income, Diluted	$ 700	$ 137	$ (825)	$ 82					$ 296	[2]	$ (691)	[2]	$ (1,039)	[2]

[1] Refer to Note 18 to the Consolidated Financial Statements for further detail.

[2] Due to the antidilutive effect of converting the Fixed Rate Cumulative Mandatorily Convertible Preferred Stock into common shares and the net loss from continuing operations attributable to common shareholders for 2012, 2011, and 2010, respectively, loss from continuing operations attributable to common shareholders and basic weighted-average common shares outstanding were used to calculate basic and diluted earnings per share.