Finance Receivables And Loans, Net (Allowance For Credit Losses On Financing Receivables) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Financing Receivable, Allowance for Loan and Lease Losses [Roll Forward]
Loans and Leases Receivable, Allowance, Beginning Balance	$ 1,054	$ 977
Allowance for Loan and Lease Losses, Write-offs	(263)	(215)
Allowance for Loan and Lease Loss, Recovery of Bad Debts	84	65
Allowance for Loan and Lease Losses Write-offs, Net	(179)	(150)
Allowance for Loan and Lease Losses, Provision for Loss, Net	220	116
Allowance for Loan and Lease Losses, Adjustments, Net	(18)	(10)
Loans and Leases Receivable, Allowance, Ending Balance	1,077	933
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for loan losses, Individually evaluated for impairment	86	90
Allowance for loan losses, Collectively evaluated for impairment	991	843
Finance receivables and loans, net	110,876	99,856	$ 111,600
Financing Receivable, Individually Evaluated for Impairment	688	596
Financing receivable, Collectively evaluated for impairment	110,188	99,260
Receivables Acquired with Deteriorated Credit Quality [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Financing Receivable, Allowance for Credit Losses	0	0
Finance receivables and loans, net	0	0
Consumer Portfolio Segment [Member] \| Automobile Loan [Member]
Financing Receivable, Allowance for Loan and Lease Losses [Roll Forward]
Loans and Leases Receivable, Allowance, Beginning Balance	834	685
Allowance for Loan and Lease Losses, Write-offs	(253)	(193)
Allowance for Loan and Lease Loss, Recovery of Bad Debts	80	61
Allowance for Loan and Lease Losses Write-offs, Net	(173)	(132)
Allowance for Loan and Lease Losses, Provision for Loss, Net	207	158
Allowance for Loan and Lease Losses, Adjustments, Net	(18)	0
Loans and Leases Receivable, Allowance, Ending Balance	850	711
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for loan losses, Individually evaluated for impairment	25	21
Allowance for loan losses, Collectively evaluated for impairment	825	690
Finance receivables and loans, net	63,013	57,447	64,292
Financing Receivable, Individually Evaluated for Impairment	337	278
Financing receivable, Collectively evaluated for impairment	62,676	57,169
Consumer Portfolio Segment [Member] \| Automobile Loan [Member] \| Receivables Acquired with Deteriorated Credit Quality [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Financing Receivable, Allowance for Credit Losses	0	0
Finance receivables and loans, net	0	0
Consumer Portfolio Segment [Member] \| Residential Mortgage [Member]
Financing Receivable, Allowance for Loan and Lease Losses [Roll Forward]
Loans and Leases Receivable, Allowance, Beginning Balance	114	152
Allowance for Loan and Lease Losses, Write-offs	(10)	(22)
Allowance for Loan and Lease Loss, Recovery of Bad Debts	4	3
Allowance for Loan and Lease Losses Write-offs, Net	(6)	(19)
Allowance for Loan and Lease Losses, Provision for Loss, Net	7	(5)
Allowance for Loan and Lease Losses, Adjustments, Net	0	(9)
Loans and Leases Receivable, Allowance, Ending Balance	115	119
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for loan losses, Individually evaluated for impairment	43	54
Allowance for loan losses, Collectively evaluated for impairment	72	65
Finance receivables and loans, net	10,675	7,652	9,773
Financing Receivable, Individually Evaluated for Impairment	261	253
Financing receivable, Collectively evaluated for impairment	10,414	7,399
Consumer Portfolio Segment [Member] \| Residential Mortgage [Member] \| Receivables Acquired with Deteriorated Credit Quality [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Financing Receivable, Allowance for Credit Losses	0	0
Finance receivables and loans, net	0	0
Commercial Portfolio Segment [Member] \| Commercial Loan [Member]
Financing Receivable, Allowance for Loan and Lease Losses [Roll Forward]
Loans and Leases Receivable, Allowance, Beginning Balance	106	140
Allowance for Loan and Lease Losses, Write-offs	0	0
Allowance for Loan and Lease Loss, Recovery of Bad Debts	0	1
Allowance for Loan and Lease Losses Write-offs, Net	0	1
Allowance for Loan and Lease Losses, Provision for Loss, Net	6	(37)
Allowance for Loan and Lease Losses, Adjustments, Net	0	(1)
Loans and Leases Receivable, Allowance, Ending Balance	112	103
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for loan losses, Individually evaluated for impairment	18	15
Allowance for loan losses, Collectively evaluated for impairment	94	88
Finance receivables and loans, net	37,188	34,757	$ 37,535
Financing Receivable, Individually Evaluated for Impairment	90	65
Financing receivable, Collectively evaluated for impairment	37,098	34,692
Commercial Portfolio Segment [Member] \| Commercial Loan [Member] \| Receivables Acquired with Deteriorated Credit Quality [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Financing Receivable, Allowance for Credit Losses	0	0
Finance receivables and loans, net	$ 0	$ 0

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

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(d))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

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

+ References

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- Definition

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

+ References

No definition available.

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- References

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- Definition

A valuation allowance for financing receivables that are expected to be uncollectible.

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- Definition

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

+ References

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- Definition

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

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- Definition

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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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953423-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953423-111524

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(d))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 6
-Section L
-Subsection 1

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.11)
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

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-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953423-111524

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