Other Real Estate Owned and Other Repossessed Assets - Expenses Related to Foreclosed and Repossessed Assets (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Other Real Estate And Foreclosed Assets [Abstract]
Net (gain) loss on sales	$ (1)	$ 80	$ 101	$ 149
Provision for unrealized losses, net	1	39	(25)	162
Operating expenses, net of rental income	41	134	190	293
Total expenses	$ 41	$ 253	$ 266	$ 604