Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Income Statement [Abstract]
Revenues	$ 13,322	$ 8,432
Cost of revenues	1,173	916
Gross profit	12,149	7,516
Operating expenses:
Selling and marketing	2,787	1,968
Research and development	3,729	2,682
General and administrative	3,668	2,700
Restructuring expense	6	104
Total operating expenses	10,190	7,454
Operating income	1,959	62
Other income (expense):
Interest income, net	86
Other expense		(10)
Income before provision for income taxes	2,045	52
Provision for income tax expense		4
Net income	$ 2,045	$ 48
Earnings per share:
Basic	$ 0.05	$ 0.00
Diluted	$ 0.05	$ 0.00
Weighted average shares outstanding:
Basic	39,482	31,297
Diluted	42,194	31,323
Preferred dividends per share		$ 25.00