Accounting for Certain Loans Acquired in a Transfer - Amounts of Loans (Parenthetical) (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2013	Dec. 31, 2012
Accounts, Notes, Loans and Financing Receivable [Line Items]
Net of allowance	$ 16,102	$ 15,992	$ 19,565	$ 18,270
Loans Purchased With Evidence Of Credit Deterioration [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Net of allowance	$ 367	$ 389