Discontinued Operations - Additional Information (Detail) (USD $) In Millions, unless otherwise specified			3 Months Ended	9 Months Ended
Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2013 Wholesale Mortgage Banking Unit [Member]	Sep. 30, 2013 Wholesale Mortgage Banking Unit [Member]	Sep. 30, 2012 Wholesale Mortgage Banking Unit [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Representations and warranties expenses for discontinued operations			$ 9	$ 303	$ 307
Representations and warranties expenses for discontinued operations, net of tax			6	190	194
Remaining assets of discontinued operations	315	309
Remaining liabilities of discontinued operations	$ 935	$ 644

Loss for representations and warranties provided by the company on loans previously sold to third parties by company's mortgage origination operations related to discontinued operations of the company's wholesale mortgage banking unit, included as a component in non-interest income (expense) before tax.

No definition available.

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- Definition

Representation and warranties expenses included in the loss of discontinued operations, net of tax.

+ References

No definition available.

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- Definition

The aggregate value (measured at the lower of net carrying value or fair value less cost of disposal) for assets of a disposal group, including a component of the entity (discontinued operation), to be sold or that has been disposed of through sale, as of the financial statement date.

+ References

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- Definition

The obligations arising from the sale, disposal, or planned sale in the near future (generally within one year) of a disposal group, including a component of the entity (discontinued operation).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 45

-Paragraph 10

-URI http://asc.fasb.org/extlink&oid=6892542&loc=d3e1107-107759

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1436-107760

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