Employee Benefits (Detail) - Information Related to Changes in Projected Benefit Obligation - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Projected benefit obligation at beginning of year	$ 38,115	$ 34,585	$ 31,605
Service cost	2,620	2,630	2,545
Interest cost	790	1,190	1,075
Actuarial loss (gain) due to assumption changes and plan experience	(1,190)	6,300	625
Additions and contractual termination benefits	85	30	460
Benefits paid	(775)	(1,350)	(1,255)
Foreign currency impact	(3,775)	(5,270)	(470)
Projected benefit obligation at end of year	$ 35,870	$ 38,115	$ 34,585