Securitizations And Variable Interest Entities (Schedule Of Cash Flow Received and Paid To Nonconsolidated Securitization Entities) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Consumer Loans Auto Financing Receivable [Member]
Cash Flow Received and Paid to Nonconsolidated Securitization Entities [Line Items]
Securitization or Asset-backed Financing Arrangement, Financial Asset for which Transfer is Accounted as Sale, Gain (Loss) on Sale	$ 1	$ 0	$ 6
Cash Flows Between Transferor and Transferee, Proceeds from New Transfers	2,594	0	1,979
Cash Flows Between Transferor and Transferee, Servicing Fees	11	13	12
Representations and warranties obligations	0	0	0
Cash Flows Between Transferor and Transferee, Receipts on Transferor's Interest in Transferred Financial Assets, Other		0	0
Cash flows received on retained interests in securitization entities			0
Purchases of previously transferred financial assets			0
US Government-sponsored Enterprises [Member]
Cash Flow Received and Paid to Nonconsolidated Securitization Entities [Line Items]
Securitization or Asset-backed Financing Arrangement, Financial Asset for which Transfer is Accounted as Sale, Gain (Loss) on Sale	0	112	629
Cash Flows Between Transferor and Transferee, Proceeds from New Transfers	0	8,676	32,796
Cash Flows Between Transferor and Transferee, Servicing Fees	0	70	693
Representations and warranties obligations	(31)	(66)	(108)
Cash Flows Between Transferor and Transferee, Receipts on Transferor's Interest in Transferred Financial Assets, Other		70	(96)
Cash flows received on retained interests in securitization entities			0
Purchases of previously transferred financial assets			(876)
Private Placement [Member]
Cash Flow Received and Paid to Nonconsolidated Securitization Entities [Line Items]
Cash Flows Between Transferor and Transferee, Proceeds from New Transfers	0	0	5
Cash Flows Between Transferor and Transferee, Servicing Fees	0	0	63
Representations and warranties obligations	0	0	(7)
Cash Flows Between Transferor and Transferee, Receipts on Transferor's Interest in Transferred Financial Assets, Other		0	255
Cash flows received on retained interests in securitization entities			71
Purchases of previously transferred financial assets			$ (12)

Cash Flow Between Transferee and Transferor representations and warranties obligations.

No definition available.

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- Definition

Cash Flows between a transferor and a transferee attributable to newly transferred assets related to either a securitization, asset-backed financing arrangement, or similar transfer in which the transferor has continuing involvement with the transferred financial assets underlying the transaction (including, but not limited to, servicing, recourse, and restrictions on transferor's interests in the transferred financial assets).

+ References

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- Definition

Cash Flows between a transferor and a transferee attributable to purchases of previously transferred financial assets (or its underlying collateral) related to a securitization, asset-backed financing arrangement, or similar transfer in which the transferor has continuing involvement with the transferred financial assets underlying the transaction (including, but not limited to, servicing, recourse, and restrictions on transferor's interests in the transferred financial assets).

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- Definition

Cash flows between transferor and a transferee attributable to the transferor's interests related to a securitization, asset-backed financing arrangement, or similar transfer in which the transferor will have continuing involvement with the transferred financial assets underlying the transaction (including, but not limited to, servicing, recourse, and restrictions on transferor's interests in the transferred financial assets).

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- Definition

Cash Flows between a transferee and a transferor attributable to servicing fees related to a securitization, asset-backed financing arrangement, or similar transfer in which the transferor has continuing involvement with the transferred financial assets underlying the transaction (including, but not limited to, servicing, recourse, and restrictions on transferor's interests in the transferred financial assets).

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- Definition

The cash inflow from the collection of a retained interest in a receivable securitized via a structured process whereby interests in loans and other receivables are packaged, underwritten, and sold in the form of asset-backed securities.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 12

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3179-108585

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- Definition

Reflects, by transferred financial asset type, the amount of sales proceeds in excess of or deficient from the sum of the carrying amounts of transferred financial assets plus transaction costs, including those transactions in which the seller/transferor has continuing involvement with the financial assets that have been transferred.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 20

-Section 50

-Paragraph 3

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=13989330&loc=d3e107207-111719

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 10

-Section 40

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=45353237&loc=d3e96813-111708

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