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
Income Statement [Abstract]
Revenues	$ 11,782	$ 6,525	$ 31,068	$ 18,933
Cost of revenues	1,011	979	2,902	3,404
Gross profit	10,771	5,546	28,166	15,529
Operating expenses:
Selling and marketing	1,793	1,311	5,529	4,488
Research and development	3,063	2,049	8,487	6,499
General and administrative	2,396	2,048	7,522	6,299
Restructuring expense	39	83	154	135
Total operating expenses	7,291	5,491	21,692	17,421
Operating income (loss)	3,480	55	6,474	(1,892)
Other income (expense):
Interest income (expense), net	87	(128)	117	(445)
Change in fair value of warrant liability		(902)		(3,126)
Gain on sale of software product			483
Other expense		(1)	(15)	(48)
Income (loss) before provision for income taxes	3,567	(976)	7,059	(5,511)
Provision for income tax expense		7	8	30
Net income (loss)	$ 3,567	$ (983)	$ 7,051	$ (5,541)
Net earnings (loss) per share:
Basic	$ 0.10	$ (0.04)	$ 0.21	$ (0.28)
Diluted	$ 0.09	$ (0.04)	$ 0.20	$ (0.28)
Weighted average shares outstanding:
Basic	36,094	25,020	33,170	20,771
Diluted	39,472	25,020	35,287	20,771
Preferred dividends per share	$ 70.50	$ 31.58	$ 104.58	$ 105.54