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		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Fair Value Disclosures [Abstract]
Impaired loans	$ (3,020)	$ (10,806)	$ (2,739)	$ (11,086)
Other real estate owned	(728)	(241)	(1,078)	(362)
Total losses	$ (3,748)	$ (11,047)	$ (3,817)	$ (11,448)