Consolidated Statements of Operations and Comprehensive Income - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Statement [Abstract]
Net sales	$ 268,245	$ 197,892	$ 164,525
Cost of products sold and services delivered	97,709	69,245	62,977
Gross margin	170,536	128,647	101,548
Operating expenses:
Sales, general and administrative	108,076	69,698	54,158
Research and development	30,609	23,614	14,885
Total operating expenses	138,685	93,312	69,043
Income from operations	31,851	35,335	32,505
Interest and other income (expense), net	(354)	26	(194)
Income before provision for income taxes	31,497	35,361	32,311
Provision for income taxes	14,200	15,428	12,393
Net income	$ 17,297	$ 19,933	$ 19,918
Net income per common and common equivalent shares:
Basic (in dollars per share)	$ 0.33	$ 0.37	$ 0.38
Diluted (in dollars per share)	$ 0.32	$ 0.36	$ 0.37
Weighted average number of common and common equivalent shares outstanding:
Basic (in shares)	52,667	53,548	52,948
Diluted (in shares)	53,536	54,638	54,500
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME
Net income	$ 17,297	$ 19,933	$ 19,918
Foreign currency translation adjustments	820	19	66
Comprehensive income	$ 18,117	$ 19,952	$ 19,984