Finance Receivables And Loans, Net (Average Balance And Interest Income Of Impaired Finance Receivables) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Financing Receivable, Impaired [Line Items]
Average balance	$ 1,050	$ 1,214	$ 1,034	$ 1,242
Impaired Financing Receivable, Interest Income, Accrual Method	20	6	29	18
Consumer Loans Auto Financing Receivable [Member]
Financing Receivable, Impaired [Line Items]
Average balance	94	0	88	0
Impaired Financing Receivable, Interest Income, Accrual Method	3	0	5	0
First Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Average balance	574	448	546	435
Impaired Financing Receivable, Interest Income, Accrual Method	7	4	11	8
Home Equity [Member]
Financing Receivable, Impaired [Line Items]
Average balance	96	90	97	88
Impaired Financing Receivable, Interest Income, Accrual Method	1	1	2	2
Residential Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Average balance	670	538	643	523
Impaired Financing Receivable, Interest Income, Accrual Method	8	5	13	10
Commercial And Industrial Automobile [Member]
Financing Receivable, Impaired [Line Items]
Average balance	185	360	197	353
Impaired Financing Receivable, Interest Income, Accrual Method	3	1	5	1
Commercial And Industrial Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Average balance	15	32	9	36
Impaired Financing Receivable, Interest Income, Accrual Method	0	0	0	5
Commercial And Industrial Other [Member]
Financing Receivable, Impaired [Line Items]
Average balance	25	99	29	113
Impaired Financing Receivable, Interest Income, Accrual Method	5	0	5	1
Commercial Real Estate Automobile [Member]
Financing Receivable, Impaired [Line Items]
Average balance	54	140	58	162
Impaired Financing Receivable, Interest Income, Accrual Method	1	0	1	0
Commercial Real Estate Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Average balance	7	45	10	55
Impaired Financing Receivable, Interest Income, Accrual Method	0	0	0	1
Commercial Loan [Member]
Financing Receivable, Impaired [Line Items]
Average balance	286	676	303	719
Impaired Financing Receivable, Interest Income, Accrual Method	$ 9	$ 1	$ 11	$ 8