Condensed Consolidated Statements of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Revenues:
Total revenues	$ 228,805	$ 204,267	$ 648,735	$ 575,559
Cost of revenues:
Total cost of revenues	116,658	105,358	335,426	305,412
Gross profit	112,147	98,909	313,309	270,147
Operating expenses:
Research and development	16,625	15,805	49,551	47,854
Selling, general, and administrative	70,876	65,609	207,588	196,831
Total operating expenses	87,501	81,414	257,139	244,685
Income from operations	24,646	17,495	56,170	25,462
Interest and other income (expense), net	(1,168)	(2,837)	(4,207)	(6,462)
Income before provision for income taxes	23,478	14,658	51,963	19,000
Provision for (benefit from) income taxes	3,495	1,030	12,720	(3,936)
Net income	$ 19,983	$ 13,628	$ 39,243	$ 22,936
Net income per share:
Net income per share - basic (in dollars per share)	$ 0.48	$ 0.35	$ 0.95	$ 0.59
Net income per share - diluted (in dollars per share)	$ 0.46	$ 0.33	$ 0.92	$ 0.57
Weighted-average shares outstanding:
Weighted-average shares outstanding — basic (in shares)	41,771	39,432	41,283	39,015
Weighted-average shares outstanding — diluted (in shares)	43,052	40,860	42,796	40,237
Product revenues
Revenues:
Total revenues	$ 168,488	$ 149,709	$ 472,477	$ 415,004
Cost of revenues:
Total cost of revenues	86,695	79,149	250,089	229,642
Services and other revenues
Revenues:
Total revenues	60,317	54,558	176,258	160,555
Cost of revenues:
Total cost of revenues	$ 29,963	$ 26,209	$ 85,337	$ 75,770