Finance Receivables And Loans, Net (Schedule of Financing Receivables, Non Accrual Status) (Details) - USD ($) $ in Millions	Jun. 30, 2016	Dec. 31, 2015	Jun. 30, 2015
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, net	$ 112,653	$ 111,600	$ 105,172
Finance receivables and loans on nonaccrual status	734	680
Consumer Portfolio Segment [Member] \| Consumer Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, net	74,365	74,065
Finance receivables and loans on nonaccrual status	612	603
Consumer Portfolio Segment [Member] \| Automobile Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, net	63,281	64,292	60,786
Finance receivables and loans on nonaccrual status	505	475
Consumer Portfolio Segment [Member] \| Residential Mortgage [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, net	11,084	9,773	9,211
Finance receivables and loans on nonaccrual status	107	128
Consumer Portfolio Segment [Member] \| Mortgage Finance [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, net	8,009	6,413
Finance receivables and loans on nonaccrual status	12	15
Consumer Portfolio Segment [Member] \| Mortgage - Legacy [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, net	3,075	3,360
Finance receivables and loans on nonaccrual status	95	113
Commercial Portfolio Segment [Member] \| Commercial Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, net	38,288	37,535	$ 35,175
Finance receivables and loans on nonaccrual status	122	77
Commercial Portfolio Segment [Member] \| Commercial And Industrial Automobile [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, net	31,640	31,469
Finance receivables and loans on nonaccrual status	51	25
Commercial Portfolio Segment [Member] \| Commercial And Industrial Other [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, net	3,037	2,640
Finance receivables and loans on nonaccrual status	64	44
Commercial Portfolio Segment [Member] \| Commercial Real Estate Automobile [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Finance receivables and loans, net	3,611	3,426
Finance receivables and loans on nonaccrual status	$ 7	$ 8

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No definition available.

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- Definition

Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5111-111524

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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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