Loans and Allowance for Loan Losses - Summary of Composition of Total TDRs (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Financing Receivable, Modifications [Line Items]
Troubled debt restructurings ("TDRs")	$ 42,062	$ 41,623
Performing [Member]
Financing Receivable, Modifications [Line Items]
Troubled debt restructurings ("TDRs")	10,289	10,220
Non-Performing [Member]
Financing Receivable, Modifications [Line Items]
Troubled debt restructurings ("TDRs")	19,384	18,698
Non-Accrual [Member]
Financing Receivable, Modifications [Line Items]
Troubled debt restructurings ("TDRs")	$ 12,389	$ 12,705