Consolidated Statements of Operations - USD ($) shares in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Net product revenue	$ 10,276,000	$ 6,862,000
Cost of revenue	3,847,000	2,824,000
Gross profit	6,429,000	4,038,000
Operating expenses:
Sales and marketing	1,604,000	1,531,000
Research and development	1,237,000	2,162,000
General and administrative	1,112,000	1,094,000
Operating income (loss)	2,476,000	(749,000)
Interest expense, net	(189,000)	(209,000)
Other income		928,000
Income (loss) from operations before income taxes	2,287,000	(30,000)
Income tax provision
Net income (loss)	2,287,000	(30,000)
Preferred stock dividends accrued	(139,000)	(139,000)
Net income (loss) attributable to common stockholders	$ 2,148,000	$ (169,000)
Net income (loss) per share attributable to common stockholders, basic (in dollars per share)	$ 0.16	$ (0.01)
Net income (loss) per share attributable to common stockholders, diluted (in dollars per share)	$ 0.14	$ (0.01)
Weighted average common shares outstanding:
Basic (in shares)	13,049	12,836
Diluted (in shares)	15,063	12,836