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, 2013	Dec. 31, 2012	Dec. 31, 2011
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	$ 0	$ 6	$ 0
Cash Flows Between Transferor and Transferee, Proceeds from New Transfers	0	1,979	0
Cash flows received on retained interests in securitization entities		0	0
Cash Flows Between Transferor and Transferee, Servicing Fees	13	12	0
Purchases of previously transferred financial assets		0	0
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	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	112	629	131
Cash Flows Between Transferor and Transferee, Proceeds from New Transfers	8,676	32,796	59,815
Cash flows received on retained interests in securitization entities		0	0
Cash Flows Between Transferor and Transferee, Servicing Fees	70	693	999
Purchases of previously transferred financial assets		(876)	(2,537)
Representations and warranties obligations	(66)	(108)	(143)
Cash Flows Between Transferor and Transferee, Receipts on Transferor's Interest in Transferred Financial Assets, Other	70	(96)	(13)
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	5	722
Cash flows received on retained interests in securitization entities		71	68
Cash Flows Between Transferor and Transferee, Servicing Fees	0	63	201
Purchases of previously transferred financial assets		(12)	(222)
Representations and warranties obligations	0	(7)	(38)
Cash Flows Between Transferor and Transferee, Receipts on Transferor's Interest in Transferred Financial Assets, Other	$ 0	$ 255	$ 187

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).

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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).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 20

-Section 50

-Paragraph 3

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

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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=25369111&loc=d3e96813-111708

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