Unaudited Condensed Consolidated Statements of Operations and Comprehensive Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Net sales	$ 99,226	$ 79,643	$ 200,441	$ 158,885
Cost of sales	36,083	34,006	72,837	64,578
Gross margin	63,143	45,637	127,604	94,307
Operating expenses:
Sales, general and administrative	39,343	31,824	75,102	62,681
Research and development	18,501	12,989	33,620	25,452
Total operating expenses	57,844	44,813	108,722	88,133
Income from operations	5,299	824	18,882	6,174
Interest and other income (expense), net	(295)	1,684	968	1,890
Income before provision for income taxes	5,004	2,508	19,850	8,064
Provision for (benefit from) income taxes	(3,481)	232	(1,561)	1,208
Net income	$ 8,485	$ 2,276	$ 21,411	$ 6,856
Net income per common and common equivalent shares:
Basic (in dollars per share)	$ 0.15	$ 0.04	$ 0.39	$ 0.13
Diluted (in dollars per share)	$ 0.15	$ 0.04	$ 0.38	$ 0.13
Weighted average number of common and common equivalent shares outstanding:
Basic (in shares)	55,527	52,736	54,330	52,578
Diluted (in shares)	57,054	53,770	55,892	53,723
UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME
Net income	$ 8,485	$ 2,276	$ 21,411	$ 6,856
Foreign currency translation adjustments	655	(716)	(52)	(551)
Comprehensive income	9,140	1,560	21,359	6,305
Product
Net sales	76,721	66,875	157,695	134,366
Cost of sales	31,087	30,172	63,521	57,244
Service
Net sales	22,505	12,768	42,746	24,519
Cost of sales	$ 4,996	$ 3,834	$ 9,316	$ 7,334