Unaudited Condensed Consolidated Statements of Operations and Comprehensive Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Income Statement [Abstract]
Net sales	$ 79,643	$ 58,756	$ 158,885	$ 114,286
Cost of products sold and services delivered	34,006	21,457	64,578	40,085
Gross margin	45,637	37,299	94,307	74,201
Operating expenses:
Sales, general and administrative	31,824	24,379	62,681	49,212
Research and development	12,989	6,710	25,452	13,637
Total operating expenses	44,813	31,089	88,133	62,849
Income from operations	824	6,210	6,174	11,352
Interest and other income (expense), net	1,684	(123)	1,890	(5)
Income before provision for income taxes	2,508	6,087	8,064	11,347
Provision for income taxes	232	2,437	1,208	4,234
Net income	$ 2,276	$ 3,650	$ 6,856	$ 7,113
Net income per common and common equivalent shares:
Basic (in dollars per share)	$ 0.04	$ 0.07	$ 0.13	$ 0.13
Diluted (in dollars per share)	$ 0.04	$ 0.07	$ 0.13	$ 0.13
Weighted average number of common and common equivalent shares outstanding:
Basic (in shares)	52,736	52,480	52,578	53,087
Diluted (in shares)	53,770	53,289	53,723	53,890
UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME
Net income	$ 2,276	$ 3,650	$ 6,856	$ 7,113
Foreign currency translation adjustments	(716)	25	(551)	259
Comprehensive income	$ 1,560	$ 3,675	$ 6,305	$ 7,372