Unaudited Condensed Consolidated Statements of Operations and Comprehensive Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Income Statement [Abstract]
Net sales	$ 58,756	$ 46,713	$ 114,286	$ 91,475
Cost of products sold and services delivered	21,457	15,990	40,085	30,884
Gross margin	37,299	30,723	74,201	60,591
Operating expenses:
Sales, general and administrative	24,379	15,443	49,212	30,008
Research and development	6,710	5,906	13,637	10,464
Total operating expenses	31,089	21,349	62,849	40,472
Income from operations	6,210	9,374	11,352	20,119
Interest income and other (expense) income, net	(123)	99	(5)	34
Income before provision for income taxes	6,087	9,473	11,347	20,153
Provision for income taxes	2,437	3,370	4,234	6,845
Net income	$ 3,650	$ 6,103	$ 7,113	$ 13,308
Net income per common and common equivalent shares:
Basic (in dollars per share)	$ 0.07	$ 0.11	$ 0.13	$ 0.25
Diluted (in dollars per share)	$ 0.07	$ 0.11	$ 0.13	$ 0.24
Weighted average number of common and common equivalent shares outstanding:
Basic (in shares)	52,480	53,644	53,087	53,407
Diluted (in shares)	53,289	54,800	53,890	54,662
UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME
Net income	$ 3,650	$ 6,103	$ 7,113	$ 13,308
Foreign currency translation adjustments	25	8	259	97
Comprehensive income	$ 3,675	$ 6,111	$ 7,372	$ 13,405