Roll Forward of Goodwill from Acquisition (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Business Combinations [Abstract]
Goodwill	$ 30,398	$ 25,809
Goodwill arising from the acquisition of GPT	107	6,258
Exchange rate impact	(2,740)	(1,669)
Goodwill	$ 27,765	$ 30,398