Additional Information Regarding on Non-Covered Loans and Covered Loans (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for Loan Losses, Individually evaluated for impairment	$ 490	$ 16,007
Allowance for Loan Losses, Collectively evaluated for impairment	136,800	142,935
Allowance for Loan Losses, Acquired loans with deteriorated credit quality	33,323	11,903
Allowance for Loan Losses	170,613	170,845
Mortgage Receivable
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for Loan Losses, Individually evaluated for impairment	490	15,877
Allowance for Loan Losses, Collectively evaluated for impairment	121,505	124,957
Allowance for Loan Losses, Acquired loans with deteriorated credit quality	14,227	4,873
Allowance for Loan Losses	136,222	145,707
Other loan
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for Loan Losses, Individually evaluated for impairment		130
Allowance for Loan Losses, Collectively evaluated for impairment	15,295	17,978
Allowance for Loan Losses, Acquired loans with deteriorated credit quality	19,096	7,030
Allowance for Loan Losses	$ 34,391	$ 25,138

The valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment

No definition available.

+ Details

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- Definition

A valuation allowance for financing receivables that are expected to be 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)(1)

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- Definition

The valuation allowance for financing receivables acquired with deteriorated credit quality.

+ References

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- Definition

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

+ References

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