Goodwill - Changes in the Carrying Value of Goodwill (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Goodwill [Roll Forward]
Goodwill, Beginning Balance	$ 81,448	$ 77,388
Goodwill, Ending Balance	95,280	81,448
Manatee Works, Inc. [Member]
Goodwill [Roll Forward]
Goodwill acquired during the period		$ 4,060
AQSense, S.L. [Member]
Goodwill [Roll Forward]
Goodwill acquired during the period	1,383
EnShape GmbH [Member]
Goodwill [Roll Forward]
Goodwill acquired during the period	8,613
Chiaro Technologies LLC [Member]
Goodwill [Roll Forward]
Goodwill acquired during the period	2,911
Webscan, Inc. [Member]
Goodwill [Roll Forward]
Goodwill acquired during the period	$ 925