Servicing Assets and Residual Interests Economic Assumptions (Detail)	9 Months Ended
Sep. 30, 2013	Sep. 30, 2012
Fixed Rate Residential Mortgage
Servicing Assets at Amortized Value
Weighted- Average Life (in years)	7 years 8 months 12 days	6 years 3 months 18 days
Prepayment Speed (annual)	8.50%	11.00%
Discount Rate (annual)	10.20%	10.30%
Adjustable Rate Residential Mortgage
Servicing Assets at Amortized Value
Weighted- Average Life (in years)	3 years 8 months 12 days	3 years 9 months 18 days
Prepayment Speed (annual)	22.40%	21.70%
Discount Rate (annual)	11.50%	11.40%

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Weighted average life of securitized assets regardless of when the transfer occurred, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (b)(2)

-URI http://asc.fasb.org/extlink&oid=13989330&loc=d3e107314-111719

+ Details

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- Definition

Discount rate which is used to value residual cash flows generated by financial assets of a securitization, asset-backed financing arrangement, or similar transfer regardless of when the transfer occurred.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (b)(1)

-URI http://asc.fasb.org/extlink&oid=13989330&loc=d3e107314-111719

+ Details

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- Definition

Estimated rate of prepayment of principal on financial assets regardless of when the transfer occurred.

+ References

+ Details

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