Finance Receivables And Loans, Net (Past Due Financing Receivables And Loans) (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2013
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	$ 1,289	$ 1,227
60 - 89 days past due	284	286
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	283	323
Total past due	1,856	1,836
Current	97,661	98,491
Loans and Leases Receivable, Gross, Excluding Fair Value Option Election	99,517	100,327
Finance receivables and loans, net	99,518	100,328	95,281
Consumer Loans Auto Financing Receivable [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	1,179	1,145
60 - 89 days past due	243	255
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	145	157
Total past due	1,567	1,557
Current	57,108	54,860
Finance receivables and loans, net	58,675	56,417
Residential Mortgage [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	110	82
60 - 89 days past due	41	31
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	138	124
Total past due	289	237
Current	7,305	8,206
Loans and Leases Receivable, Gross, Excluding Fair Value Option Election	7,594	8,443
Finance receivables and loans, net	7,595	8,444
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	0	42
Total past due	0	42
Current	33,248	35,425
Finance receivables and loans, net	33,248	35,467
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	0	36
Total past due	0	36
Current	28,453	30,912
Finance receivables and loans, net	28,453	30,948
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	0
Total past due	0	0
Current	1,756	1,664
Finance receivables and loans, net	1,756	1,664
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	0	6
Total past due	0	6
Current	3,039	2,849
Finance receivables and loans, net	$ 3,039	$ 2,855