Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Income Statement [Abstract]
Restricted cash	$ 1,200
Revenues
Revenues	86,263	$ 75,343
Cost of revenues	18,495	17,709
Gross profit	67,768	57,634
Operating expenses:
Research and development	17,983	15,837
Sales and marketing	18,230	17,315
General and administrative	11,124	10,431
Total operating expenses	47,337	43,583
Income from operations	20,431	14,051
Other income (expense), net:
Interest expense	(3)	(42)
Interest income	1,924	2,051
Other expense, net	(135)	(223)
Total other income, net	1,786	1,786
Income before income taxes	22,217	15,837
Provision for income taxes	3,523	2,571
Net income	$ 18,694	$ 13,266
Net income per share:
Basic (USD per share)	$ 0.48	$ 0.34
Diluted (USD per share)	$ 0.46	$ 0.32
Weighted average shares used in computing net income per share:
Basic (shares)	39,112	39,109
Diluted (shares)	40,846	41,546