Other Real Estate Owned and Other Repossessed Assets - Valuation Allowance Related to Real Estate Owned (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Other Real Estate And Foreclosed Assets [Abstract]
Beginning of period	$ 1,124	$ 1,244	$ 1,229	$ 1,423
Additions charged to expense	(27)	42	(26)	123
Reductions due to sales	(96)	(91)	(202)	(351)
End of period	$ 1,001	$ 1,195	$ 1,001	$ 1,195