Fair Values of Assets and Liabilities - Losses Realized on Assets Measured on Non-Recurring Basis (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Fair Value Disclosures [Abstract]
Impaired loans	$ (3,996)	$ (503)
Other real estate owned	(363)	(131)
Total losses	$ (4,359)	$ (634)