Finance Receivables And Loans, Net (Past Due Financing Receivables And Loans) (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	$ 1,055	$ 1,416
60 - 89 days past due	204	327
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	263	288
Total past due	1,522	2,031
Current	98,334	97,916
Loans and Leases Receivable, Gross, Excluding Fair Value Option Election	99,856	99,947	99,623
Finance receivables and loans, net	99,857	99,948
Consumer Loans Auto Financing Receivable [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	968	1,340
60 - 89 days past due	182	293
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	148	164
Total past due	1,298	1,797
Current	56,149	54,773
Finance receivables and loans, net	57,447	56,570
Residential Mortgage [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	87	76
60 - 89 days past due	22	25
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	107	124
Total past due	216	225
Current	7,436	7,248
Loans and Leases Receivable, Gross, Excluding Fair Value Option Election	7,652	7,473
Finance receivables and loans, net	7,653	7,474
Commercial Loan [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	0	0
60 - 89 days past due	0	9
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	8	0
Total past due	8	9
Current	34,749	35,895
Finance receivables and loans, net	34,757	35,904
Commercial And Industrial Automobile [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	0	0
60 - 89 days past due	0	9
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	8	0
Total past due	8	9
Current	29,536	30,862
Finance receivables and loans, net	29,544	30,871
Commercial And Industrial Other [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	0	0
60 - 89 days past due	0	0
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	0	0
Total past due	0	0
Current	2,004	1,882
Finance receivables and loans, net	2,004	1,882
Commercial Real Estate Automobile [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30 - 59 days past due	0	0
60 - 89 days past due	0	0
Financing Receivable, Recorded Investment, Equal to Greater than 90 Days Past Due	0	0
Total past due	0	0
Current	3,209	3,151
Finance receivables and loans, net	$ 3,209	$ 3,151

Loans and Leases Receivable, Gross, Excluding Fair Value Option Election

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- Definition

Financing receivables that are less than 60 days past due but more than 29 days past due.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 7A

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953401-111524

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Financing receivables that are less than 90 days past due but more than 59 days past due.

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Financing receivables that are current.

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Financing receivables that are equal to or greater than 90 days past due.

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Recorded Investment in financing receivables that are past due at the balance sheet date.

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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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