Finance Receivables And Loans, Net (Allowance For Credit Losses On Financing Receivables) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans and Leases Receivable, Allowance, Beginning Balance	$ 1,208	$ 1,170
Allowance for Loan and Lease Losses, Write-offs	(776)	(737)
Allowance for Loan and Lease Loss, Recovery of Bad Debts	239	265
Allowance for Loan and Lease Losses Write-offs, Net	(537)	(472)
Provision for Loan and Lease Losses	457us-gaap_ProvisionForLoanAndLeaseLosses	501us-gaap_ProvisionForLoanAndLeaseLosses
Allowance for Loan and Lease Losses, Adjustments, Net	(151)	9
Loans and Leases Receivable, Allowance, Ending Balance	977	1,208
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for loan losses, Individually evaluated for impairment	106	248
Allowance for loan losses, Collectively evaluated for impairment	871	960
Allowance for loan losses, Loans acquired with deteriorated credit quality	0	0
Finance receivables and loans, net	99,948	100,328
Loans and Leases Receivable, Gross, Excluding Fair Value Option Election	99,947	100,327
Financing Receivable, Individually Evaluated for Impairment	700	1,404
Financing receivable, Collectively evaluated for impairment	99,246	98,915
Financing receivable, Loans acquired with deteriorated credit quality	1	8
Consumer Loans Auto Financing Receivable [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans and Leases Receivable, Allowance, Beginning Balance	673	575
Allowance for Loan and Lease Losses, Write-offs	(720)	(639)
Allowance for Loan and Lease Loss, Recovery of Bad Debts	219	237
Allowance for Loan and Lease Losses Write-offs, Net	(501)	(402)
Provision for Loan and Lease Losses	540	490
Allowance for Loan and Lease Losses, Adjustments, Net	(27)	10
Loans and Leases Receivable, Allowance, Ending Balance	685	673
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for loan losses, Individually evaluated for impairment	23	23
Allowance for loan losses, Collectively evaluated for impairment	662	650
Allowance for loan losses, Loans acquired with deteriorated credit quality	0	0
Finance receivables and loans, net	56,570	56,417
Financing Receivable, Individually Evaluated for Impairment	282	281
Financing receivable, Collectively evaluated for impairment	56,287	56,128
Financing receivable, Loans acquired with deteriorated credit quality	1	8
Residential Mortgage [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans and Leases Receivable, Allowance, Beginning Balance	389	452
Allowance for Loan and Lease Losses, Write-offs	(51)	(93)
Allowance for Loan and Lease Loss, Recovery of Bad Debts	8	18
Allowance for Loan and Lease Losses Write-offs, Net	(43)	(75)
Provision for Loan and Lease Losses	(69)	13
Allowance for Loan and Lease Losses, Adjustments, Net	(125)	(1)
Loans and Leases Receivable, Allowance, Ending Balance	152	389
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for loan losses, Individually evaluated for impairment	62	199
Allowance for loan losses, Collectively evaluated for impairment	90	190
Allowance for loan losses, Loans acquired with deteriorated credit quality	0	0
Finance receivables and loans, net	7,473	8,443
Financing Receivable, Individually Evaluated for Impairment	336	919
Financing receivable, Collectively evaluated for impairment	7,137	7,524
Financing receivable, Loans acquired with deteriorated credit quality	0	0
Commercial Loan [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans and Leases Receivable, Allowance, Beginning Balance	146	143
Allowance for Loan and Lease Losses, Write-offs	(5)	(5)
Allowance for Loan and Lease Loss, Recovery of Bad Debts	12	10
Allowance for Loan and Lease Losses Write-offs, Net	7	5
Provision for Loan and Lease Losses	(14)	(2)
Allowance for Loan and Lease Losses, Adjustments, Net	1	0
Loans and Leases Receivable, Allowance, Ending Balance	140	146
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for loan losses, Individually evaluated for impairment	21	26
Allowance for loan losses, Collectively evaluated for impairment	119	120
Allowance for loan losses, Loans acquired with deteriorated credit quality	0	0
Finance receivables and loans, net	35,904	35,467
Financing Receivable, Individually Evaluated for Impairment	82	204
Financing receivable, Collectively evaluated for impairment	35,822	35,263
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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The balance of financing receivables that were collectively 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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