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, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Average Recorded Investment	$ 1,483	$ 1,050	$ 1,437	$ 1,034
Impaired Financing Receivable, Interest Income, Accrual Method	15	20	29	29
Consumer Loans Auto Financing Receivable [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Average Recorded Investment	275	94	273	88
Impaired Financing Receivable, Interest Income, Accrual Method	5	3	9	5
Residential Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Average Recorded Investment	928	670	899	643
Impaired Financing Receivable, Interest Income, Accrual Method	7	8	15	13
First Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Average Recorded Investment	781	574	760	546
Impaired Financing Receivable, Interest Income, Accrual Method	5	7	12	11
Home Equity [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Average Recorded Investment	147	96	139	97
Impaired Financing Receivable, Interest Income, Accrual Method	2	1	3	2
Commercial Loan [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Average Recorded Investment	280	286	265	303
Impaired Financing Receivable, Interest Income, Accrual Method	3	9	5	11
Commercial And Industrial Automobile [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Average Recorded Investment	177	185	167	197
Impaired Financing Receivable, Interest Income, Accrual Method	1	3	3	5
Commercial And Industrial Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Average Recorded Investment	0	15	0	9
Impaired Financing Receivable, Interest Income, Accrual Method	0	0	0	0
Commercial And Industrial Other [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Average Recorded Investment	68	25	63	29
Impaired Financing Receivable, Interest Income, Accrual Method	1	5	1	5
Commercial Real Estate Automobile [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Average Recorded Investment	35	54	35	58
Impaired Financing Receivable, Interest Income, Accrual Method	1	1	1	1
Commercial Real Estate Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Average Recorded Investment	0	7	0	10
Impaired Financing Receivable, Interest Income, Accrual Method	$ 0	$ 0	$ 0	$ 0