Segment And Geographic Information (Financial Information Operating Segments) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Segment Reporting Information [Line Items]
Net financing revenue (loss)	$ 970	$ 889	$ 2,736	$ 2,576
Other revenue	332	375	786	1,061
Total net revenue (loss)	1,302	1,264	3,522	3,637
Provision for loan losses	211	102	467	302
Total noninterest expense	674	742	2,093	2,276
Income (loss) from continuing operations before income tax expense	417	420	962	1,059
Assets	156,105	149,195	156,105	149,195	$ 151,828
Net Interest Income (Loss) after Provision for Loan Losses	759	787	2,300	2,300
Automotive finance operations [Member]
Segment Reporting Information [Line Items]
Net financing revenue (loss)	870	850	2,529	2,554
Other revenue	63	69	170	195
Total net revenue (loss)	933	919	2,699	2,749
Provision for loan losses	201	109	460	367
Total noninterest expense	385	395	1,160	1,167
Income (loss) from continuing operations before income tax expense	347	415	1,079	1,215
Assets	113,843	110,937	113,843	110,937
Insurance Operations [Member]
Segment Reporting Information [Line Items]
Net financing revenue (loss)	16	16	42	47
Other revenue	233	287	769	849
Total net revenue (loss)	249	303	811	896
Provision for loan losses	0	0	0	0
Total noninterest expense	209	243	678	785
Income (loss) from continuing operations before income tax expense	40	60	133	111
Assets	6,997	7,178	6,997	7,178
Mortgage Operations [Member]
Segment Reporting Information [Line Items]
Net financing revenue (loss)	20	9	50	35
Other revenue	10	0	84	13
Total net revenue (loss)	30	9	134	48
Provision for loan losses	6	(7)	4	(55)
Total noninterest expense	17	19	46	62
Income (loss) from continuing operations before income tax expense	7	(3)	84	41
Assets	9,772	7,402	9,772	7,402
Corporate And Other [Member]
Segment Reporting Information [Line Items]
Net financing revenue (loss)	64	14	115	(60)
Other revenue	26	19	(237)	4
Total net revenue (loss)	90	33	(122)	(56)
Provision for loan losses	4	0	3	(10)
Total noninterest expense	63	85	209	262
Income (loss) from continuing operations before income tax expense	23	(52)	(334)	(308)
Assets	25,493	23,678	25,493	23,678
Corporate Finance Operations [Member]
Segment Reporting Information [Line Items]
Assets	$ 2,300	$ 1,700	$ 2,300	$ 1,700