Indemnification Asset/Liability - Summary of Activity in Balance of Indemnification Asset (Liability) (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
FDIC Indemnification Asset [Roll Forward]
Beginning (payable) receivable balance	$ (662)	$ (466)	$ (521)	$ (349)
Effect of actual covered losses and change in estimated future covered losses	17	(15)	(210)	(59)
Change in estimated true up liability		(13)	(35)	(57)
Reimbursable expenses (revenue), net		3	(4)
Payments made (received)	107	(1)	232	(27)
Ending (payable) receivable balance	(538)	(492)	(538)	(492)
Amount of indemnification asset recorded in other assets			95	92
Amount of indemnification liability recorded in other liabilities			(633)	(584)
Ending balance	$ (662)	$ (466)	$ (538)	$ (492)