Finance Receivables And Loans, Net (Redefaults) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Modifications, Number of Contracts	17,913	20,497
Financing Receivable, Modifications, Pre-Modification Recorded Investment	$ 362	$ 712
Financing Receivable, Modifications, Post-Modification Recorded Investment	332	618
Financing Receivable, Modifications, Subsequent Default, Number of Contracts	7,144	6,070
Financing Receivable, Modifications, Subsequent Default, Recorded Investment	92	83
Financing Receivables, Impaired, Troubled Debt Restructuring, Write-down	48	38
Consumer Loans Auto Financing Receivable [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Modifications, Number of Contracts	17,511	19,388
Financing Receivable, Modifications, Pre-Modification Recorded Investment	211	297
Financing Receivable, Modifications, Post-Modification Recorded Investment	187	249
Financing Receivable, Modifications, Subsequent Default, Number of Contracts	7,117	6,038
Financing Receivable, Modifications, Subsequent Default, Recorded Investment	90	75
Financing Receivables, Impaired, Troubled Debt Restructuring, Write-down	47	37
Residential Mortgage [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Modifications, Number of Contracts	396	1,092
Financing Receivable, Modifications, Pre-Modification Recorded Investment	80	278
Financing Receivable, Modifications, Post-Modification Recorded Investment	74	234
Financing Receivable, Modifications, Subsequent Default, Number of Contracts	27	32
Financing Receivable, Modifications, Subsequent Default, Recorded Investment	2	8
Financing Receivables, Impaired, Troubled Debt Restructuring, Write-down	1	1
Commercial Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Modifications, Number of Contracts	6	17
Financing Receivable, Modifications, Pre-Modification Recorded Investment	71	137
Financing Receivable, Modifications, Post-Modification Recorded Investment	71	135
Financing Receivable, Modifications, Subsequent Default, Number of Contracts	0	0
Financing Receivable, Modifications, Subsequent Default, Recorded Investment	0	0
Financing Receivables, Impaired, Troubled Debt Restructuring, Write-down	0	0
Commercial And Industrial Automobile [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Modifications, Number of Contracts	3	8
Financing Receivable, Modifications, Pre-Modification Recorded Investment	23	37
Financing Receivable, Modifications, Post-Modification Recorded Investment	23	37
Financing Receivable, Modifications, Subsequent Default, Number of Contracts	0	0
Financing Receivable, Modifications, Subsequent Default, Recorded Investment	0	0
Financing Receivables, Impaired, Troubled Debt Restructuring, Write-down	0	0
Commercial And Industrial Other [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Modifications, Number of Contracts	3	4
Financing Receivable, Modifications, Pre-Modification Recorded Investment	48	80
Financing Receivable, Modifications, Post-Modification Recorded Investment	48	78
Commercial Real Estate Automobile [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Modifications, Number of Contracts	0	5
Financing Receivable, Modifications, Pre-Modification Recorded Investment	0	20
Financing Receivable, Modifications, Post-Modification Recorded Investment	0	20
Commercial Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Modifications, Subsequent Default, Number of Contracts	0	0
Financing Receivable, Modifications, Subsequent Default, Recorded Investment	0	0
Financing Receivables, Impaired, Troubled Debt Restructuring, Write-down	$ 0	$ 0

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Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 33

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953676-111524

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Post-modification amount of investment in financing receivables modified by troubled debt restructurings.

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Pre-modification amount of investment in financing receivables modified by troubled debt restructurings.

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 34

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953682-111524

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Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default.

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- Definition

Reflects the amount of the write-down related to a troubled debt restructuring.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 40

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=25495931&loc=d3e18845-111554

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