Estimated Funded Status (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation at beginning of year	$ 7,682	$ 7,073
Service cost	50	38	$ 66
Interest cost	62	46	91
Actuarial (gain) loss	75	302
Benefits paid	(560)	(222)
Other	11	7
Foreign exchange impact	(12)	438
Benefit obligation at end of year	7,308	7,682	7,073
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	908	743
Return on plan assets	31	5
Employer contributions	110	88
Benefits paid	(185)	0
Foreign exchange impact	(29)	72
Fair value of plan assets at end of year	835	908	$ 743
Plan assets less than benefit obligation - Net amount recognized	$ (6,473)	$ (6,774)