Condensed Consolidated Statements of Operations - 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
Revenues	$ 82,671	$ 71,658	$ 236,943	$ 204,689
Cost of revenues	17,108	16,511	52,354	48,660
Gross profit	65,563	55,147	184,589	156,029
Operating expenses:
Research and development	16,899	12,501	50,431	38,182
Sales and marketing	17,009	15,489	51,489	50,698
General and administrative	9,106	9,040	29,961	29,731
Total operating expenses	43,014	37,030	131,881	118,611
Income from operations	22,549	18,117	52,708	37,418
Other income (expense), net:
Interest expense	(28)	(35)	(98)	(112)
Interest income	2,142	1,651	6,391	4,193
Other income (expense), net	(328)	(500)	(320)	(836)
Total other income, net	1,786	1,116	5,973	3,245
Income before income taxes	24,335	19,233	58,681	40,663
Provision (benefit) for income taxes	5,161	(4,236)	10,009	(2,241)
Net income	$ 19,174	$ 23,469	$ 48,672	$ 42,904
Net income per share:
Basic (USD per share)	$ 0.49	$ 0.60	$ 1.24	$ 1.10
Diluted (USD per share)	$ 0.47	$ 0.56	$ 1.17	$ 1.02
Weighted average shares used in computing net income per share:
Basic (shares)	39,014	39,170	39,099	38,907
Diluted (shares)	41,162	42,197	41,447	42,113