Other Real Estate Owned and Other Repossessed Assets - Real Estate Owned and Other Repossessed Assets (Detail) - USD ($) $ in Thousands	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013
Other Real Estate Owned And Other Repossessed Assets [Abstract]
Real estate owned and other repossessed assets	$ 4,556		$ 4,890
Valuation allowance	(1,195)	$ (1,244)	(1,423)	$ (3,563)	$ (3,588)	$ (4,059)
End of period	$ 3,361		$ 3,467