Finance Receivables And Loans, Net (Impaired Financing Receivables) (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	$ 597	$ 704
Carrying value before allowance	596	700
Impaired Financing Receivable, Related Allowance	90	106
Consumer Loans Auto Financing Receivable [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	278	282
Carrying value before allowance	278	282
Impaired Financing Receivable, Related Allowance	21	23
Residential Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	254	340
Carrying value before allowance	253	336
Impaired Financing Receivable, Related Allowance	54	62
Commercial Loan [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	65	82
Carrying value before allowance	65	82
Impaired Financing Receivable, Related Allowance	15	21
Commercial And Industrial Automobile [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	35	32
Carrying value before allowance	35	32
Impaired Financing Receivable, Related Allowance	6	5
Commercial And Industrial Other [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	26	46
Carrying value before allowance	26	46
Impaired Financing Receivable, Related Allowance	8	15
Commercial Real Estate Automobile [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	4	4
Carrying value before allowance	4	4
Impaired Financing Receivable, Related Allowance	1	1
Impaired With No Allowance Member
Financing Receivable, Impaired [Line Items]
Carrying value before allowance	68	91
Impaired With No Allowance Member | Consumer Loans Auto Financing Receivable [Member]
Financing Receivable, Impaired [Line Items]
Carrying value before allowance	0	0
Impaired With No Allowance Member | Residential Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Carrying value before allowance	62	86
Impaired With No Allowance Member | Commercial Loan [Member]
Financing Receivable, Impaired [Line Items]
Carrying value before allowance	6	5
Impaired With No Allowance Member | Commercial And Industrial Automobile [Member]
Financing Receivable, Impaired [Line Items]
Carrying value before allowance	5	4
Impaired With No Allowance Member | Commercial And Industrial Other [Member]
Financing Receivable, Impaired [Line Items]
Carrying value before allowance	0	0
Impaired With No Allowance Member | Commercial Real Estate Automobile [Member]
Financing Receivable, Impaired [Line Items]
Carrying value before allowance	1	1
Impaired With Allowance Member
Financing Receivable, Impaired [Line Items]
Carrying value before allowance	528	609
Impaired With Allowance Member | Consumer Loans Auto Financing Receivable [Member]
Financing Receivable, Impaired [Line Items]
Carrying value before allowance	278	282
Impaired With Allowance Member | Residential Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Carrying value before allowance	191	250
Impaired With Allowance Member | Commercial Loan [Member]
Financing Receivable, Impaired [Line Items]
Carrying value before allowance	59	77
Impaired With Allowance Member | Commercial And Industrial Automobile [Member]
Financing Receivable, Impaired [Line Items]
Carrying value before allowance	30	28
Impaired With Allowance Member | Commercial And Industrial Other [Member]
Financing Receivable, Impaired [Line Items]
Carrying value before allowance	26	46
Impaired With Allowance Member | Commercial Real Estate Automobile [Member]
Financing Receivable, Impaired [Line Items]
Carrying value before allowance	$ 3	$ 3