Finance Receivables And Loans, Net (Allowance For Credit Losses On Financing Receivables) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Financing Receivable, Allowance for Loan and Lease Losses [Roll Forward]
Loans and Leases Receivable, Allowance, Beginning Balance	$ 977	$ 1,208
Allowance for Loan and Lease Losses, Write-offs	(215)	(196)
Allowance for Loan and Lease Loss, Recovery of Bad Debts	65	63
Allowance for Loan and Lease Losses Write-offs, Net	(150)	(133)
Allowance for Loan and Lease Losses, Provision for Loss, Net	116us-gaap_ProvisionForLoanAndLeaseLosses	137us-gaap_ProvisionForLoanAndLeaseLosses
Allowance for Loan and Lease Losses, Adjustments, Net	(10)	(20)
Loans and Leases Receivable, Allowance, Ending Balance	933	1,192
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for loan losses, Individually evaluated for impairment	90	248
Allowance for loan losses, Collectively evaluated for impairment	843	944
Allowance for loan losses, Loans acquired with deteriorated credit quality	0	0
Finance receivables and loans, net	99,857		99,948
Loans and Leases Receivable, Gross, Excluding Fair Value Option Election	99,856	99,623	99,947
Financing Receivable, Individually Evaluated for Impairment	596	1,398
Financing receivable, Collectively evaluated for impairment	99,260	98,220
Financing receivable, Loans acquired with deteriorated credit quality	0	5
Consumer Loans Auto Financing Receivable [Member]
Financing Receivable, Allowance for Loan and Lease Losses [Roll Forward]
Loans and Leases Receivable, Allowance, Beginning Balance	685	673
Allowance for Loan and Lease Losses, Write-offs	(193)	(180)
Allowance for Loan and Lease Loss, Recovery of Bad Debts	61	59
Allowance for Loan and Lease Losses Write-offs, Net	(132)	(121)
Allowance for Loan and Lease Losses, Provision for Loss, Net	158	163
Allowance for Loan and Lease Losses, Adjustments, Net	0	0
Loans and Leases Receivable, Allowance, Ending Balance	711	715
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for loan losses, Individually evaluated for impairment	21	23
Allowance for loan losses, Collectively evaluated for impairment	690	692
Allowance for loan losses, Loans acquired with deteriorated credit quality	0	0
Finance receivables and loans, net	57,447	56,775
Financing Receivable, Individually Evaluated for Impairment	278	290
Financing receivable, Collectively evaluated for impairment	57,169	56,480
Financing receivable, Loans acquired with deteriorated credit quality	0	5
Residential Mortgage [Member]
Financing Receivable, Allowance for Loan and Lease Losses [Roll Forward]
Loans and Leases Receivable, Allowance, Beginning Balance	152	389
Allowance for Loan and Lease Losses, Write-offs	(22)	(15)
Allowance for Loan and Lease Loss, Recovery of Bad Debts	3	3
Allowance for Loan and Lease Losses Write-offs, Net	(19)	(12)
Allowance for Loan and Lease Losses, Provision for Loss, Net	(5)	(23)
Allowance for Loan and Lease Losses, Adjustments, Net	(9)	(21)
Loans and Leases Receivable, Allowance, Ending Balance	119	333
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for loan losses, Individually evaluated for impairment	54	200
Allowance for loan losses, Collectively evaluated for impairment	65	133
Allowance for loan losses, Loans acquired with deteriorated credit quality	0	0
Finance receivables and loans, net	7,652	8,137
Financing Receivable, Individually Evaluated for Impairment	253	935
Financing receivable, Collectively evaluated for impairment	7,399	7,202
Financing receivable, Loans acquired with deteriorated credit quality	0	0
Commercial Loan [Member]
Financing Receivable, Allowance for Loan and Lease Losses [Roll Forward]
Loans and Leases Receivable, Allowance, Beginning Balance	140	146
Allowance for Loan and Lease Losses, Write-offs	0	(1)
Allowance for Loan and Lease Loss, Recovery of Bad Debts	1	1
Allowance for Loan and Lease Losses Write-offs, Net	1	0
Allowance for Loan and Lease Losses, Provision for Loss, Net	(37)	(3)
Allowance for Loan and Lease Losses, Adjustments, Net	(1)	1
Loans and Leases Receivable, Allowance, Ending Balance	103	144
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for loan losses, Individually evaluated for impairment	15	25
Allowance for loan losses, Collectively evaluated for impairment	88	119
Allowance for loan losses, Loans acquired with deteriorated credit quality	0	0
Finance receivables and loans, net	34,757	34,711
Financing Receivable, Individually Evaluated for Impairment	65	173
Financing receivable, Collectively evaluated for impairment	34,692	34,538
Financing receivable, Loans acquired with deteriorated credit quality	$ 0	$ 0

Loans and Leases Receivable, Gross, Excluding Fair Value Option Election

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Amount of other addition (reduction) in allowance reserve for credit loss.

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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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Amount, after recoveries, of loans and leases that have been written-off.

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Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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The balance of financing receivables that were acquired with deteriorated credit quality.

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The valuation allowance for financing receivables acquired with deteriorated credit quality.

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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Amount of expense related to estimated loss from loan and lease transactions.

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