Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Revenue:
Revenue	$ 342,958	$ 442,575	$ 410,561
Cost of revenue:
Cost of revenue	198,806	262,939	260,314
Gross profit	144,152	179,636	150,247
Operating expenses:
Research and development	53,931	51,876	43,071
Sales and marketing	34,290	34,608	28,532
General and administrative	31,726	33,193	30,802
Total operating expenses	119,947	119,677	102,405
Income from operations	24,205	59,959	47,842
Other (expense) income:
Interest income	2,955	2,328	714
Interest expense	(5,155)	(5,110)	(5,121)
Other, net	(1,083)	(2,472)	396
Total other expense	(3,283)	(5,254)	(4,011)
Income before income taxes	20,922	54,705	43,831
Income tax provision (benefit)	3,888	8,820	(83,128)
Net income	$ 17,034	$ 45,885	$ 126,959
Net income per share:
Basic (in dollars per share)	$ 0.52	$ 1.42	$ 4.11
Diluted (in dollars per share)	$ 0.50	$ 1.35	$ 3.80
Shares used in computing net income per share:
Basic weighted average common shares	32,559	32,286	30,866
Diluted weighted average common shares	33,828	34,002	33,436
Product
Revenue:
Revenue	$ 319,505	$ 415,922	$ 387,124
Cost of revenue:
Cost of revenue	175,732	236,446	234,932
Services
Revenue:
Revenue	23,453	26,653	23,437
Cost of revenue:
Cost of revenue	$ 23,074	$ 26,493	$ 25,382