Consolidated Statements of Operations and Comprehensive Loss - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Income Statement [Abstract]
Revenues	$ 7,214	$ 10,529
Cost of revenues	2,113	2,118
Gross profit	5,101	8,411
Operating expenses:
Selling and marketing	2,370	2,191
Research and development	3,923	3,341
General and administrative	2,486	2,877
Total operating expenses	8,779	8,409
Operating income (loss)	(3,678)	2
Interest and other income (expense), net	(2)	(1)
Income (loss) before provision for income taxes	(3,680)	1
Provision for income tax expense	26	11
Net loss	(3,706)	(10)
Other comprehensive income, before tax:
Unrealized holding gains on available-for-sale securities	2	1
Other comprehensive income, net of tax	2	1
Comprehensive loss	$ (3,704)	$ (9)
Net loss per share:
Basic and diluted	$ (0.08)	$ 0.00
Weighted average shares outstanding:
Basic and diluted	46,094	45,501