Finance Receivables And Loans, Net (Impaired Financing Receivables) (Details) (USD $) In Millions, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	$ 1,514	$ 1,434
Carrying value before allowance	1,509	1,349
Impaired Financing Receivable, Related Allowance	262	228
Consumer Loans Auto Financing Receivable [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	268	260
Carrying value before allowance	268	260
Impaired Financing Receivable, Related Allowance	22	16
Residential Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	941	958
Carrying value before allowance	936	873
Impaired Financing Receivable, Related Allowance	214	186
First Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	795	811
Carrying value before allowance	789	725
Impaired Financing Receivable, Related Allowance	162	137
Home Equity [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	146	147
Carrying value before allowance	147	148
Impaired Financing Receivable, Related Allowance	52	49
Commercial Loan [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	305	216
Carrying value before allowance	305	216
Impaired Financing Receivable, Related Allowance	26	26
Commercial And Industrial Automobile [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	186	146
Carrying value before allowance	186	146
Impaired Financing Receivable, Related Allowance	9	7
Commercial And Industrial Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	0	0
Carrying value before allowance	0	0
Impaired Financing Receivable, Related Allowance	0	0
Commercial And Industrial Other [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	88	33
Carrying value before allowance	88	33
Impaired Financing Receivable, Related Allowance	7	7
Commercial Real Estate Automobile [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	31	37
Carrying value before allowance	31	37
Impaired Financing Receivable, Related Allowance	10	12
Commercial Real Estate Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	0	0
Carrying value before allowance	0	0
Impaired Financing Receivable, Related Allowance	0	0
Impaired With No Allowance Member
Financing Receivable, Impaired [Line Items]
Carrying value before allowance	222	286
Impaired With No Allowance Member | Consumer Loans Auto Financing Receivable [Member]
Financing Receivable, Impaired [Line Items]
Carrying value before allowance	0	90
Impaired With No Allowance Member | Residential Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Carrying value before allowance	128	124
Impaired With No Allowance Member | First Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Carrying value before allowance	126	123
Impaired With No Allowance Member | Home Equity [Member]
Financing Receivable, Impaired [Line Items]
Carrying value before allowance	2	1
Impaired With No Allowance Member | Commercial Loan [Member]
Financing Receivable, Impaired [Line Items]
Carrying value before allowance	94	72
Impaired With No Allowance Member | Commercial And Industrial Automobile [Member]
Financing Receivable, Impaired [Line Items]
Carrying value before allowance	69	54
Impaired With No Allowance Member | Commercial And Industrial Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Carrying value before allowance	0	0
Impaired With No Allowance Member | Commercial And Industrial Other [Member]
Financing Receivable, Impaired [Line Items]
Carrying value before allowance	17	9
Impaired With No Allowance Member | Commercial Real Estate Automobile [Member]
Financing Receivable, Impaired [Line Items]
Carrying value before allowance	8	9
Impaired With No Allowance Member | Commercial Real Estate Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Carrying value before allowance	0	0
Impaired With Allowance Member
Financing Receivable, Impaired [Line Items]
Carrying value before allowance	1,287	1,063
Impaired With Allowance Member | Consumer Loans Auto Financing Receivable [Member]
Financing Receivable, Impaired [Line Items]
Carrying value before allowance	268	170
Impaired With Allowance Member | Residential Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Carrying value before allowance	808	749
Impaired With Allowance Member | First Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Carrying value before allowance	663	602
Impaired With Allowance Member | Home Equity [Member]
Financing Receivable, Impaired [Line Items]
Carrying value before allowance	145	147
Impaired With Allowance Member | Commercial Loan [Member]
Financing Receivable, Impaired [Line Items]
Carrying value before allowance	211	144
Impaired With Allowance Member | Commercial And Industrial Automobile [Member]
Financing Receivable, Impaired [Line Items]
Carrying value before allowance	117	92
Impaired With Allowance Member | Commercial And Industrial Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Carrying value before allowance	0	0
Impaired With Allowance Member | Commercial And Industrial Other [Member]
Financing Receivable, Impaired [Line Items]
Carrying value before allowance	71	24
Impaired With Allowance Member | Commercial Real Estate Automobile [Member]
Financing Receivable, Impaired [Line Items]
Carrying value before allowance	23	28
Impaired With Allowance Member | Commercial Real Estate Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Carrying value before allowance	$ 0	$ 0