Summarized Information on Changes in Plan Obligations and Plan Assets (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation, beginning of year	$ 14,210	$ 7,876
Service cost	1,729	1,081
Interest cost	134	163
Plan participants' contributions	546	486
Actuarial loss (gain)	93	3,057
Plan change	(495)
Employee vested funds brought to plan, net	(382)	2,183
Expenses paid from assets	(25)
Translation gain	(86)	(636)
Benefit obligation, end of year	15,724	14,210
Fair value of plan assets, beginning of year	9,620	5,998
Actual return on plan assets	170	130
Employer contributions	1,471	1,285
Plan participants' contributions	546	483
Employee vested funds brought to plan, net	(382)	2,183
Expenses paid from assets	(25)
Translation loss	(99)	(459)
Fair value of plan assets, end of year	11,301	9,620
Unfunded liability, end of year	$ 4,423	$ 4,590