Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Income Statement [Abstract]
Net product revenue	$ 6,619	$ 13,643
Cost of revenue	2,709	5,342
Gross profit	3,910	8,301
Operating expenses:
Sales and marketing	3,821	1,298
Research and development	3,797	1,314
General and administrative	2,815	1,182
Operating income (loss)	(6,523)	4,507
Interest expense	(6)	(46)
Interest income	11	4
Income (loss) from operations before income taxes	(6,518)	4,465
Income tax provision	0	0
Net income (loss)	(6,518)	4,465
Preferred stock dividends accrued	(79)	(139)
Net income (loss) attributable to common stockholders	$ (6,597)	$ 4,326
Net income (loss) per share attributable to common stockholders, basic	$ (0.45)	$ 0.32
Net income (loss) per share attributable to common stockholders, diluted	$ (0.45)	$ 0.28
Weighted average common shares outstanding:
Basic (in shares)	14,678	13,502
Diluted (in shares)	14,678	15,352