Finance Receivables And Loans, Net (Past Due Financing Receivables And Loans) (Details) (USD $) In Millions, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012	Jun. 30, 2012
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	$ 959	$ 1,001
60 - 89 days past due	226	256
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	305	337
Total past due	1,490	1,594
Current	95,503	97,461
Finance receivables and loans, net	96,993	99,055	119,913
Consumer Loans Auto Financing Receivable [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	868	920
60 - 89 days past due	193	213
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	134	138
Total past due	1,195	1,271
Current	54,833	52,444
Finance receivables and loans, net	56,028	53,715
Residential Mortgage [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	91	81
60 - 89 days past due	33	43
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	143	174
Total past due	267	298
Current	9,003	9,523
Finance receivables and loans, net	9,270	9,821
First Mortgage [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	79	66
60 - 89 days past due	28	37
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	131	156
Total past due	238	259
Current	6,536	6,914
Finance receivables and loans, net	6,774	7,173
Home Equity [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	12	15
60 - 89 days past due	5	6
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	12	18
Total past due	29	39
Current	2,467	2,609
Finance receivables and loans, net	2,496	2,648
Commercial Loan [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	28	25
Total past due	28	25
Current	31,667	35,494
Finance receivables and loans, net	31,695	35,519
Commercial And Industrial Automobile [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	20	16
Total past due	20	16
Current	27,498	30,254
Finance receivables and loans, net	27,518	30,270
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	0	0
Finance receivables and loans, net	0	0
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	0	1
Total past due	0	1
Current	1,502	2,696
Finance receivables and loans, net	1,502	2,697
Commercial Real Estate Automobile [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	8	8
Total past due	8	8
Current	2,667	2,544
Finance receivables and loans, net	2,675	2,552
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	0
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	0	0
Total past due	0	0
Current	0	0
Finance receivables and loans, net	$ 0	$ 0