Estimated Funded Status (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation at beginning of year	$ 8,194	$ 8,482
Service cost	66	65	$ 64
Interest cost	91	119	111
Actuarial (gain) loss	(481)	15
Benefits paid	(1,000)	(1,165)
Curtailments	0	(536)
Other	0	1,412
Foreign exchange impact	203	(198)
Benefit obligation at end of year	7,073	8,194	8,482
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	718	380
Return on plan assets	7	19
Employer contributions	6	14
Acquisitions	0	331
Foreign exchange impact	12	(26)
Fair value of plan assets at end of year	743	718	$ 380
Plan assets less than benefit obligation - Net amount recognized	$ (6,330)	$ (7,476)