CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Income Statement [Abstract]
Revenue, Product and Service [Extensible List]			Product [Member]
Product sales, net	$ 33,718	$ 31,020	$ 106,025	$ 77,712
Other revenue	788	1,238	2,568	1,238
Total revenue	34,506	32,258	$ 108,593	78,950
Cost, Product and Service [Extensible List]			Product [Member]
Cost of product sales	12,408	9,787	$ 36,600	28,369
Gross profit	22,098	22,471	71,993	50,581
Research and development	4,284	2,913	12,363	9,902
Selling, general and administrative	22,775	16,041	71,625	50,596
Total operating expenses	27,059	18,954	83,988	60,498
Income (loss) from operations	(4,961)	3,517	(11,995)	(9,917)
Other income (expense):
Interest income	44	121	163	574
Interest expense	(1)	(2)	(3)	(5)
Other income (expense)	(13)	(18)	45	(8)
Total other income	30	101	205	561
Income (loss) before tax expense	(4,931)	3,618	(11,790)	(9,356)
Tax expense	0	0	(215)	0
Net income (loss)	$ (4,931)	$ 3,618	$ (12,006)	$ (9,356)
Net income (loss) per common share (Basic) (in USD per share)	$ (0.11)	$ 0.08	$ (0.26)	$ (0.21)
Net income (loss) per common share (Diluted) (in USD per share)	$ (0.11)	$ 0.08	$ (0.26)	$ (0.21)
Weighted average common shares outstanding (Basic) (in shares)	46,669	45,272	46,355	45,112
Weighted average common shares outstanding (Diluted) (in shares)	46,669	47,314	46,355	45,112