Consolidated Statements of Operations and Comprehensive Income - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Net sales	$ 681,003	$ 530,860	$ 420,068
Cost of sales	264,672	223,574	161,485
Gross margin	416,331	307,286	258,583
Sales, general and administrative	307,286	212,959	156,886
Research and development	123,195	100,721	76,856
Total operating expenses	430,481	313,680	233,742
Income (loss) from operations	(14,150)	(6,394)	24,841
Interest and other income, net	7,859	8,464	3,263
Income (loss) before provision for income taxes	(6,291)	2,070	28,104
Provision (benefit) for income taxes	(4,567)	1,188	(1,101)
Net income (loss)	$ (1,724)	$ 882	$ 29,205
Net income (loss) per share:
Basic (in dollars per share)	$ (0.03)	$ 0.01	$ 0.52
Diluted (in dollars per share)	$ (0.03)	$ 0.01	$ 0.50
Weighted average shares outstanding:
Basic (in shares)	61,782	59,190	56,392
Diluted (in shares)	61,782	60,018	57,922
Net income (loss)	$ (1,724)	$ 882	$ 29,205
Foreign currency translation adjustments	1,237	417	(46)
Comprehensive income (loss)	(487)	1,299	29,159
Product
Net sales	500,250	399,474	327,635
Cost of sales	224,131	190,683	139,337
Service
Net sales	180,753	131,386	92,433
Cost of sales	$ 40,541	$ 32,891	$ 22,148