Unaudited Condensed Consolidated Statements of Operations and Comprehensive Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Net sales	$ 115,810	$ 101,215
Cost of sales	46,893	36,754
Gross margin	68,917	64,461
Operating expenses:
Sales, general and administrative	42,892	35,759
Research and development	23,354	15,119
Total operating expenses	66,246	50,878
Income from operations	2,671	13,583
Interest and other income, net	2,313	1,263
Income before provision for income taxes	4,984	14,846
Provision for (benefit from) income taxes	(1,435)	1,920
Net income	$ 6,419	$ 12,926
Net income per common and common equivalent shares:
Basic (in dollars per share)	$ 0.11	$ 0.24
Diluted (in dollars per share)	$ 0.11	$ 0.24
Weighted average number of common and common equivalent shares outstanding:
Basic (in shares)	58,914	53,119
Diluted (in shares)	59,751	54,532
UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME
Net income	$ 6,419	$ 12,926
Foreign currency translation adjustments	50	(707)
Comprehensive income	6,469	12,219
Product
Net sales	88,089	80,974
Cost of sales	39,600	32,434
Service
Net sales	27,721	20,241
Cost of sales	$ 7,293	$ 4,320