Loans Receivable and Allowance for Loan Losses - Schedule of Changes in Allowance for Loan Losses (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Receivables [Abstract]
Beginning Balance	$ 30,932	$ 23,998
Provision for loan losses	3,635	2,901
Charge-offs	(1,144)	(536)
Recoveries	143	341
Ending balance	$ 33,566	$ 26,704

Amount of recovery of financing receivables doubtful of collection that were previously charged off.

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Amount of direct write-downs of financing receivables charged against the allowance.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

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Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

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