Finance Receivables And Loans, Net (Allowance For Credit Losses On Financing Receivables) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013
Financing Receivable, Allowance for Loan and Lease Losses [Roll Forward]
Loans and Leases Receivable, Allowance, Beginning Balance	$ 1,208	$ 1,170
Allowance for Loan and Lease Losses, Write-offs	(196)	(167)
Allowance for Loan and Lease Loss, Recovery of Bad Debts	63	53
Allowance for Loan and Lease Losses Write-offs, Net	(133)	(114)
Allowance for Loan and Lease Losses, Provision for Loss, Net	137	131
Allowance for Loan and Lease Losses, Adjustments, Net	(20)	10
Loans and Leases Receivable, Allowance, Ending Balance	1,192	1,197
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for loan losses, Individually evaluated for impairment	248	259
Allowance for loan losses, Collectively evaluated for impairment	944	936
Allowance for loan losses, Loans acquired with deteriorated credit quality	0	2
Finance receivables and loans, net	99,624	99,123	100,328
Loans and Leases Receivable, Gross, Excluding Fair Value Option Election	99,623		100,327
Financing Receivable, Individually Evaluated for Impairment	1,398	2,600
Financing receivable, Collectively evaluated for impairment	98,220	96,501
Financing receivable, Loans acquired with deteriorated credit quality	5	22
Consumer Loans Auto Financing Receivable [Member]
Financing Receivable, Allowance for Loan and Lease Losses [Roll Forward]
Loans and Leases Receivable, Allowance, Beginning Balance	673	575
Allowance for Loan and Lease Losses, Write-offs	(180)	(142)
Allowance for Loan and Lease Loss, Recovery of Bad Debts	59	49
Allowance for Loan and Lease Losses Write-offs, Net	(121)	(93)
Allowance for Loan and Lease Losses, Provision for Loss, Net	163	107
Allowance for Loan and Lease Losses, Adjustments, Net	0	10
Loans and Leases Receivable, Allowance, Ending Balance	715	599
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for loan losses, Individually evaluated for impairment	23	22
Allowance for loan losses, Collectively evaluated for impairment	692	575
Allowance for loan losses, Loans acquired with deteriorated credit quality	0	2
Finance receivables and loans, net	56,775	55,014
Financing Receivable, Individually Evaluated for Impairment	290	270
Financing receivable, Collectively evaluated for impairment	56,480	54,722
Financing receivable, Loans acquired with deteriorated credit quality	5	22
Residential Mortgage [Member]
Financing Receivable, Allowance for Loan and Lease Losses [Roll Forward]
Loans and Leases Receivable, Allowance, Beginning Balance	389	452
Allowance for Loan and Lease Losses, Write-offs	(15)	(24)
Allowance for Loan and Lease Loss, Recovery of Bad Debts	3	3
Allowance for Loan and Lease Losses Write-offs, Net	(12)	(21)
Allowance for Loan and Lease Losses, Provision for Loss, Net	(23)	20
Allowance for Loan and Lease Losses, Adjustments, Net	(21)	0
Loans and Leases Receivable, Allowance, Ending Balance	333	451
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for loan losses, Individually evaluated for impairment	200	209
Allowance for loan losses, Collectively evaluated for impairment	133	242
Allowance for loan losses, Loans acquired with deteriorated credit quality	0	0
Finance receivables and loans, net	8,137	9,672
Financing Receivable, Individually Evaluated for Impairment	935	933
Financing receivable, Collectively evaluated for impairment	7,202	8,739
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	146	143
Allowance for Loan and Lease Losses, Write-offs	(1)	(1)
Allowance for Loan and Lease Loss, Recovery of Bad Debts	1	1
Allowance for Loan and Lease Losses Write-offs, Net	0	0
Allowance for Loan and Lease Losses, Provision for Loss, Net	(3)	4
Allowance for Loan and Lease Losses, Adjustments, Net	1	0
Loans and Leases Receivable, Allowance, Ending Balance	144	147
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for loan losses, Individually evaluated for impairment	25	28
Allowance for loan losses, Collectively evaluated for impairment	119	119
Allowance for loan losses, Loans acquired with deteriorated credit quality	0	0
Finance receivables and loans, net	34,711	34,437
Financing Receivable, Individually Evaluated for Impairment	173	1,397
Financing receivable, Collectively evaluated for impairment	34,538	33,040
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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No definition available.

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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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The balance of financing receivables 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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-Number Topic 6

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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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