Other Income - Schedule of Other Income (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Other Income and Expenses [Abstract]
Foreign currency (losses) gains	$ (359)	$ 55	$ (287)	$ 140
Tax indemnification income	687	490	1,528	980
Other	8	7	15	9
Other income	$ 336	$ 552	$ 1,256	$ 1,129