CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Income Statement [Abstract]
Revenue, Product and Service [Extensible List]			Product [Member]
Product sales, net	$ 36,826	$ 38,680	$ 72,678	$ 72,307
Other revenue	220	839	442	1,780
Total revenue	37,046	39,519	$ 73,120	74,087
Cost, Product and Service [Extensible List]			Product [Member]
Cost of product sales	14,192	12,609	$ 26,814	24,192
Gross profit	22,854	26,910	46,306	49,895
Research and development	4,792	4,449	9,652	8,079
Selling, general and administrative	27,144	26,190	53,009	48,850
Total operating expenses	31,936	30,639	62,661	56,929
Loss from operations	(9,082)	(3,729)	(16,355)	(7,034)
Other income (expense):
Interest income	148	43	236	119
Interest expense	(20)	(1)	(38)	(2)
Other income (expense)	(9)	(27)	103	57
Total other income	119	15	301	174
Loss before income taxes	(8,963)	(3,714)	(16,054)	(6,860)
Income tax expense	0	72	0	215
Net loss	$ (8,963)	$ (3,786)	$ (16,054)	$ (7,075)
Net loss per common share:
Basic (in USD per share)	$ (0.19)	$ (0.08)	$ (0.34)	$ (0.15)
Diluted (in USD per share)	$ (0.19)	$ (0.08)	$ (0.34)	$ (0.15)
Weighted-average common shares outstanding:
Basic (in shares)	47,117	46,403	47,052	46,195
Diluted (in shares)	47,117	46,403	47,052	46,195