Changes in the Corporation's Liability of Estimated Losses from Credit Recourses Agreements (Detail) (Guarantee on loans sold or serviced with credit recourse, USD $) In Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Guarantee on loans sold or serviced with credit recourse
Guarantor Obligations [Line Items]
Balance as of beginning of period	$ 55,318	$ 29,041	$ 53,729	$ 15,584
Additions for new sales
Provision	10,059	12,015	19,824	27,716
Net charge-offs / terminations	(10,050)	(4,449)	(18,226)	(6,693)
Balance as of end of period	$ 55,327	$ 36,607	$ 55,327	$ 36,607

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- Definition

Total of allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 09
-Article 12

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e24092-122690

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- Definition

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Total of the deductions in a given period to allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs, representing receivables written off as uncollectible and portions of the reserves utilized, respectively.

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