Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Revenues	$ 897,027	$ 787,309	$ 712,714
Cost of revenues	460,115	414,979	394,077
Gross profit	436,912	372,330	318,637
Operating expenses:
Research and development	68,644	64,843	66,022
Selling, general, and administrative	289,916	263,095	241,470
Total operating expenses	358,560	327,938	307,492
Income from operations	78,352	44,392	11,145
Interest and other income (expense), net	(4,419)	(8,776)	(6,633)
Income (loss) before provision for income taxes	73,933	35,616	4,512
Provision for (benefit from) income taxes	12,595	(2,113)	(26,006)
Net income	$ 61,338	$ 37,729	$ 30,518
Net income per share:
Basic (in dollars per share)	$ 1.48	$ 0.96	$ 0.81
Diluted (in dollars per share)	$ 1.43	$ 0.93	$ 0.79
Weighted-average shares outstanding:
Basic (in shares)	41,462	39,242	37,483
Diluted (in shares)	42,943	40,559	38,712
Product [Member]
Revenues	$ 659,602	$ 569,595	$ 510,201
Cost of revenues	344,914	312,360	304,842
Service [Member]
Revenues	237,425	217,714	202,513
Cost of revenues	$ 115,201	$ 102,619	$ 89,235