Parent And Guarantor Consolidating Financial Statements (Schedule of Consolidating Statement of Income) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Condensed Income Statements, Captions [Line Items]
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 on deposits	203	177	396	349
Interest on short-term borrowings	12	12	25	23
Interest on long-term debt	436	419	878	848
Interest Expense, Debt	0	0	0	0
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
Bank Subsidiary		0		0
Nonbank subsidiaries	0	0	0	0
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
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
(Loss) income from continuing operations before income tax (benefit) expense and undistributed income of subsidiaries	413	263	810	545
Income tax expense (benefit) from continuing operations	56	94	206	197
Income (Loss) from Continuing Operations Attributable to Parent	357	169	604	348
Income (loss) from discontinued operations, net of tax	3	13	6	410
Undistributed income of bank subsidiaries	0	0	0	0
Undistributed income of nonbank subsidiaries	0	0	0	0
Net income (loss)	360	182	610	758
Other Comprehensive Income (Loss), Net of Tax	120	(148)	266	(117)
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	480	34	876	641
Parent [Member]
Condensed Income Statements, Captions [Line Items]
Interest and fees on finance receivables and loans	(28)	(16)	(66)	(12)
Interest on loans held-for-sale		0		0
Interest and dividends on investment securities	0	0	0	0
Interest on cash and cash equivalents	1	1	2	1
Operating leases	5	0	10	0
Total financing revenue and other interest income	(19)	(13)	(48)	1
Interest on deposits	2	2	4	5
Interest on short-term borrowings	10	10	20	20
Interest on long-term debt	290	292	578	584
Interest Expense, Debt	4	6	9	25
Total interest expense	306	310	611	634
Depreciation expense on operating lease assets	3	0	7	0
Net financing revenue (loss)	(328)	(323)	(666)	(633)
Bank Subsidiary		400		525
Nonbank subsidiaries	148	248	629	486
Insurance premiums and service revenue earned	0	0	0	0
Gain (loss) on mortgage and automotive loans, net	(2)	0	(5)	(8)
Loss on extinguishment of debt		(156)	(2)	(353)
Other gain on investments, net	0	0	0	0
Other income, net of losses	317	327	690	678
Total other revenue	315	171	683	317
Total net revenue (loss)	135	496	646	695
Provision for loan losses	88	(36)	148	64
Compensation and benefits expense	139	139	286	293
Insurance losses and loss adjustment expenses	0	0	0	0
Other operating expenses	317	310	656	620
Total noninterest expense	456	449	942	913
(Loss) income from continuing operations before income tax (benefit) expense and undistributed income of subsidiaries	(409)	83	(444)	(282)
Income tax expense (benefit) from continuing operations	(65)	(87)	(108)	(202)
Income (Loss) from Continuing Operations Attributable to Parent	(344)	170	(336)	(80)
Income (loss) from discontinued operations, net of tax	3	(15)	9	372
Undistributed income of bank subsidiaries	336	(132)	607	48
Undistributed income of nonbank subsidiaries	365	159	330	418
Net income (loss)	360	182	610	758
Other Comprehensive Income (Loss), Net of Tax	120	(148)	266	(117)
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	480	34	876	641
Guarantor Subsidiaries [Member]
Condensed Income Statements, Captions [Line Items]
Interest and fees on finance receivables and loans	0	0	0	0
Interest on loans held-for-sale		0		0
Interest and dividends on investment securities	0	0	0	0
Interest on cash and cash equivalents	0	0	0	0
Operating leases	0	0	0	0
Total financing revenue and other interest income	0	0	0	0
Interest on deposits	0	0	0	0
Interest on short-term borrowings	0	0	0	0
Interest on long-term debt	0	0	0	0
Interest Expense, Debt	0	0	0	0
Total interest expense	0	0	0	0
Depreciation expense on operating lease assets	0	0	0	0
Net financing revenue (loss)	0	0	0	0
Bank Subsidiary		400		525
Nonbank subsidiaries	0	0	0	0
Insurance premiums and service revenue earned	0	0	0	0
Gain (loss) on mortgage and automotive loans, net	0	0	0	0
Loss on extinguishment of debt		0	0	0
Other gain on investments, net	0	0	0	0
Other income, net of losses	0	0	0	0
Total other revenue	0	0	0	0
Total net revenue (loss)	0	400	0	525
Provision for loan losses	0	0	0	0
Compensation and benefits expense	0	0	0	0
Insurance losses and loss adjustment expenses	0	0	0	0
Other operating expenses	0	0	0	0
Total noninterest expense	0	0	0	0
(Loss) income from continuing operations before income tax (benefit) expense and undistributed income of subsidiaries	0	400	0	525
Income tax expense (benefit) from continuing operations	(82)	0	(82)	0
Income (Loss) from Continuing Operations Attributable to Parent	82	400	82	525
Income (loss) from discontinued operations, net of tax	0	0	0	0
Undistributed income of bank subsidiaries	336	(132)	607	48
Undistributed income of nonbank subsidiaries	(2)	0	(2)	0
Net income (loss)	416	268	687	573
Other Comprehensive Income (Loss), Net of Tax	62	(67)	145	(25)
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	478	201	832	548
Non-Guarantor Subsidiaries [Member]
Condensed Income Statements, Captions [Line Items]
Interest and fees on finance receivables and loans	1,293	1,134	2,566	2,204
Interest on loans held-for-sale		14		38
Interest and dividends on investment securities	99	93	201	181
Interest on cash and cash equivalents	3	1	5	3
Operating leases	696	860	1,460	1,756
Total financing revenue and other interest income	2,095	2,109	4,241	4,207
Interest on deposits	201	175	392	344
Interest on short-term borrowings	2	2	5	3
Interest on long-term debt	146	127	300	264
Interest Expense, Debt	3	3	6	12
Total interest expense	352	307	703	623
Depreciation expense on operating lease assets	431	563	937	1,185
Net financing revenue (loss)	1,312	1,239	2,601	2,399
Bank Subsidiary		0		0
Nonbank subsidiaries	0	0	0	0
Insurance premiums and service revenue earned	236	237	466	470
Gain (loss) on mortgage and automotive loans, net	5	1	9	55
Loss on extinguishment of debt		0	(2)	(1)
Other gain on investments, net	39	45	93	100
Other income, net of losses	214	334	430	690
Total other revenue	494	617	996	1,314
Total net revenue (loss)	1,806	1,856	3,597	3,713
Provision for loan losses	84	176	244	192
Compensation and benefits expense	103	197	208	422
Insurance losses and loss adjustment expenses	145	122	218	178
Other operating expenses	502	533	1,044	1,083
Total noninterest expense	750	852	1,470	1,683
(Loss) income from continuing operations before income tax (benefit) expense and undistributed income of subsidiaries	972	828	1,883	1,838
Income tax expense (benefit) from continuing operations	203	181	396	399
Income (Loss) from Continuing Operations Attributable to Parent	769	647	1,487	1,439
Income (loss) from discontinued operations, net of tax	0	28	(3)	38
Undistributed income of bank subsidiaries	0	0	0	0
Undistributed income of nonbank subsidiaries	0	0	0	0
Net income (loss)	769	675	1,484	1,477
Other Comprehensive Income (Loss), Net of Tax	91	(166)	243	(119)
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	860	509	1,727	1,358
Consolidation, Eliminations [Member]
Condensed Income Statements, Captions [Line Items]
Interest and fees on finance receivables and loans	0	0	0	0
Interest on loans held-for-sale		0		0
Interest and dividends on investment securities	0	0	0	0
Interest on cash and cash equivalents	0	0	0	0
Operating leases	0	0	0	0
Total financing revenue and other interest income	(7)	(9)	(15)	(37)
Interest on deposits	0	0	0	0
Interest on short-term borrowings	0	0	0	0
Interest on long-term debt	0	0	0	0
Interest Expense, Debt	(7)	(9)	(15)	(37)
Total interest expense	(7)	(9)	(15)	(37)
Depreciation expense on operating lease assets	0	0	0	0
Net financing revenue (loss)	0	0	0	0
Bank Subsidiary		(800)		(1,050)
Nonbank subsidiaries	(148)	(248)	(629)	(486)
Insurance premiums and service revenue earned	0	0	0	0
Gain (loss) on mortgage and automotive loans, net	0	0	0	0
Loss on extinguishment of debt		0	0	0
Other gain on investments, net	0	0	0	0
Other income, net of losses	(435)	(577)	(929)	(1,177)
Total other revenue	(435)	(577)	(929)	(1,177)
Total net revenue (loss)	(583)	(1,625)	(1,558)	(2,713)
Provision for loan losses	0	0	0	0
Compensation and benefits expense	0	(100)	0	(224)
Insurance losses and loss adjustment expenses	0	0	0	0
Other operating expenses	(433)	(477)	(929)	(953)
Total noninterest expense	(433)	(577)	(929)	(1,177)
(Loss) income from continuing operations before income tax (benefit) expense and undistributed income of subsidiaries	(150)	(1,048)	(629)	(1,536)
Income tax expense (benefit) from continuing operations	0	0	0	0
Income (Loss) from Continuing Operations Attributable to Parent	(150)	(1,048)	(629)	(1,536)
Income (loss) from discontinued operations, net of tax	0	0	0	0
Undistributed income of bank subsidiaries	(672)	264	(1,214)	(96)
Undistributed income of nonbank subsidiaries	(363)	(159)	(328)	(418)
Net income (loss)	(1,185)	(943)	(2,171)	(2,050)
Other Comprehensive Income (Loss), Net of Tax	(153)	233	(388)	144
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	(1,338)	(710)	(2,559)	(1,906)
Affiliated Entity [Member]
Condensed Income Statements, Captions [Line Items]
Interest and fees on finance receivables and loans	0	0	0	0
Interest on cash and cash equivalents	0	0	0	0
Affiliated Entity [Member] | Parent [Member]
Condensed Income Statements, Captions [Line Items]
Interest and fees on finance receivables and loans	3	2	6	12
Interest on cash and cash equivalents	0	0	0	0
Affiliated Entity [Member] | Guarantor Subsidiaries [Member]
Condensed Income Statements, Captions [Line Items]
Interest and fees on finance receivables and loans	0	0	0	0
Interest on cash and cash equivalents	0	0	0	0
Affiliated Entity [Member] | Non-Guarantor Subsidiaries [Member]
Condensed Income Statements, Captions [Line Items]
Interest and fees on finance receivables and loans	2	5	4	21
Interest on cash and cash equivalents	2	2	5	4
Affiliated Entity [Member] | Consolidation, Eliminations [Member]
Condensed Income Statements, Captions [Line Items]
Interest and fees on finance receivables and loans	(5)	(7)	(10)	(33)
Interest on cash and cash equivalents	$ (2)	$ (2)	$ (5)	$ (4)