Employee Benefits (Detail) - Information Related to Changes in Projected Benefit Obligation - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Projected benefit obligation at beginning of year	$ 35,870	$ 38,115	$ 34,585
Service cost	2,780	2,620	2,630
Interest cost	850	790	1,190
Actuarial loss (gain) due to assumption changes and plan experience	1,480	(1,190)	6,300
Additions and contractual termination benefits	0	85	30
Benefits paid	(1,640)	(775)	(1,350)
Foreign currency impact	(940)	(3,775)	(5,270)
Projected benefit obligation at end of year	$ 38,400	$ 35,870	$ 38,115