Finance Receivables And Loans, Net (Impaired Financing Receivables) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	$ 704	$ 1,409
Carrying value before allowance	700	1,404
Impaired Financing Receivable, Related Allowance	106	248
Consumer Loans Auto Financing Receivable [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	282	281
Carrying value before allowance	282	281
Impaired Financing Receivable, Related Allowance	23	23
Residential Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	340	924
Carrying value before allowance	336	919
Impaired Financing Receivable, Related Allowance	62	199
Commercial Loan [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	82	204
Carrying value before allowance	82	204
Impaired Financing Receivable, Related Allowance	21	26
Commercial And Industrial Automobile [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	32	116
Carrying value before allowance	32	116
Impaired Financing Receivable, Related Allowance	5	7
Commercial And Industrial Other [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	46	74
Carrying value before allowance	46	74
Impaired Financing Receivable, Related Allowance	15	16
Commercial Real Estate Automobile [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	4	14
Carrying value before allowance	4	14
Impaired Financing Receivable, Related Allowance	1	3
Impaired With No Allowance Member
Financing Receivable, Impaired [Line Items]
Carrying value before allowance	91	194
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	86	128
Impaired With No Allowance Member | Commercial Loan [Member]
Financing Receivable, Impaired [Line Items]
Carrying value before allowance	5	66
Impaired With No Allowance Member | Commercial And Industrial Automobile [Member]
Financing Receivable, Impaired [Line Items]
Carrying value before allowance	4	57
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	9
Impaired With Allowance Member
Financing Receivable, Impaired [Line Items]
Carrying value before allowance	609	1,210
Impaired With Allowance Member | Consumer Loans Auto Financing Receivable [Member]
Financing Receivable, Impaired [Line Items]
Carrying value before allowance	282	281
Impaired With Allowance Member | Residential Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Carrying value before allowance	250	791
Impaired With Allowance Member | Commercial Loan [Member]
Financing Receivable, Impaired [Line Items]
Carrying value before allowance	77	138
Impaired With Allowance Member | Commercial And Industrial Automobile [Member]
Financing Receivable, Impaired [Line Items]
Carrying value before allowance	28	59
Impaired With Allowance Member | Commercial And Industrial Other [Member]
Financing Receivable, Impaired [Line Items]
Carrying value before allowance	46	74
Impaired With Allowance Member | Commercial Real Estate Automobile [Member]
Financing Receivable, Impaired [Line Items]
Carrying value before allowance	$ 3	$ 5