Condensed Consolidated Statements of Comprehensive Income (Loss) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Statement of Comprehensive Income [Abstract]
Revenue (Note 7)	$ 24,568	$ 22,090
Cost of revenue	5,516	6,104
Gross profit	19,052	15,986
Operating expenses:
Research and development	5,915	4,870
Sales and marketing	1,931	3,618
General and administrative	6,939	10,524
Total operating expenses	14,785	19,012
Income (loss) from operations	4,267	(3,026)
Other (expense) income:
Interest expense	(227)	0
Interest income	0	166
Total other (expense) income	(227)	166
Income (loss) before income taxes	4,040	(2,860)
Income tax expense (benefit)	1,581	(870)
Net income (loss)	2,459	(1,990)
Total comprehensive income (loss)	$ 2,459	$ (1,990)
Earnings (loss) per share:
Basic (in dollars per share)	$ 0.06	$ (0.05)
Diluted (in dollars per share)	$ 0.06	$ (0.05)
Shares used in computing earnings (loss) per share:
Basic (in shares)	42,977	42,703
Diluted (in shares)	44,670	42,703