Loans and Allowance for Loan Losses - Additional Information (Detail) (USD $)	Dec. 31, 2011	Dec. 31, 2010
Accounts, Notes, Loans and Financing Receivable [Line Items]
Deferred loan fee income	$ 60,200,000	$ 45,500,000
Loans modified in TDRs	34,275,000
Unfunded commitments available for funding	$ 1,100,000

Reflects the cumulative amount of interest and fees paid by borrowers which have not yet been taken into income in conformity with GAAP. Also reflects the amount of unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans that are being amortized into income as an adjustment to yield.

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+ Details