Benefit Plans - Components of Net Periodic Benefit Cost (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Defined Benefit Plan Net Periodic Benefit Cost [Abstract]
Service cost		$ 70
Interest cost	$ 239	335
Expected return on plan assets	(246)	(448)
Amortization of transition obligation		70
Amortization of net (gain) loss	42	29
Effect of settlement	224
Net period benefit cost	$ 259	$ 56