Allowance for Loan and Lease Losses on Covered Loans for the Previous Five Quarters (Detail) (USD $) In Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance at beginning of period	$ 31,555	$ 16,493	$ 11,583	$ 1,273	$ 0	$ 16,493	$ 0
Provision for loan and lease losses	23,895	26,016	13,997	20,725	18,962	49,911	28,422
Loans charged-off	(7,456)	(14,026)	(9,351)	(10,492)	(17,689)	(21,482)	(27,149)
Recoveries	3,050	3,072	264	77	0	6,122	0
Balance at end of period	$ 51,044	$ 31,555	$ 16,493	$ 11,583	$ 1,273	$ 51,044	$ 1,273

Allowance for losses on loans subject to loss share agreements.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Financing Receivable Allowance For Credit Losses Recoveries Previous Write Off

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The sum of the periodic provision charged to operations, based on an assessment of the uncollectibility of the loan and lease portfolio on covered loans, the offset to which is either added to or deducted from the allowance account for the purpose of reducing loan receivable and leases to an amount that approximates their net realizable value (the amount expected to be collected).

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Reduction to the allowance for credit losses related to financing receivables deemed uncollectible.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-URI http://asc.fasb.org/extlink&oid=6965416&loc=SL6953423-111524
-Subparagraph (c)(3)

+ Details

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Period Type:	duration