Finance Receivables And Loans, Net (Past Due Financing Receivables And Loans) (Details) (USD $) In Millions, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	$ 842	$ 916
60 - 89 days past due	209	212
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	426	532
Total past due	1,477	1,660
Current	118,436	112,260
Loans and Leases Receivable Excluding Fair Value Option Election	119,913	113,920
Consumer Loans Auto Financing Receivable [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	738	802
60 - 89 days past due	161	162
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	181	179
Total past due	1,080	1,143
Current	67,056	62,316
Loans and Leases Receivable Excluding Fair Value Option Election	68,136	63,459
First Mortgage [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	80	91
60 - 89 days past due	34	35
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	169	162
Total past due	283	288
Current	6,747	6,603
Loans and Leases Receivable Excluding Fair Value Option Election	7,030	6,891
Home Equity [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	15	21
60 - 89 days past due	8	11
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	14	18
Total past due	37	50
Current	2,756	3,052
Loans and Leases Receivable Excluding Fair Value Option Election	2,793	3,102
Residential Mortgage [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	95	112
60 - 89 days past due	42	46
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	183	180
Total past due	320	338
Current	9,503	9,655
Loans and Leases Receivable Excluding Fair Value Option Election	9,823	9,993
Commercial And Industrial Automobile [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	9	0
60 - 89 days past due	4	1
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	47	126
Total past due	60	127
Current	35,787	34,690
Loans and Leases Receivable Excluding Fair Value Option Election	35,847	34,817
Commercial And Industrial Mortgage [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	0	0
60 - 89 days past due	0	0
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	0	0
Total past due	0	0
Current	1,146	1,911
Loans and Leases Receivable Excluding Fair Value Option Election	1,146	1,911
Commercial And Industrial Other [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	0	0
60 - 89 days past due	0	0
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	1	1
Total past due	1	1
Current	2,434	1,240
Loans and Leases Receivable Excluding Fair Value Option Election	2,435	1,241
Commercial Real Estate Automobile [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	0	2
60 - 89 days past due	2	1
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	14	34
Total past due	16	37
Current	2,510	2,448
Loans and Leases Receivable Excluding Fair Value Option Election	2,526	2,485
Commercial Real Estate Mortgage [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	0	0
60 - 89 days past due	0	2
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	0	12
Total past due	0	14
Current	0	0
Loans and Leases Receivable Excluding Fair Value Option Election	0	14
Commercial Loan [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	9	2
60 - 89 days past due	6	4
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	62	173
Total past due	77	179
Current	41,877	40,289
Loans and Leases Receivable Excluding Fair Value Option Election	$ 41,954	$ 40,468