Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Revenue:
Total revenue	$ 130,581	$ 138,144	$ 117,243
Costs and expenses:
Research and development	37,944	36,461	31,640
Selling, general and administrative	98,888	97,901	84,478
Total costs and expenses	198,040	189,180	169,082
Loss from operations	(67,459)	(51,036)	(51,839)
Interest expense	(3,823)	(3,572)	(4,279)
Surplus funding from NIH Contract	7,140	0	0
Loss from extinguishment of debt	(9)	0	(12,020)
Other income, net	491	507	1,433
Loss before income taxes	(63,660)	(54,101)	(66,705)
Income tax benefit	4,423	1,081	1,915
Net loss	$ (59,237)	$ (53,020)	$ (64,790)
Net loss per share, basic (in usd per share)	$ (0.78)	$ (0.74)	$ (0.97)
Net loss per share, diluted (in usd per share)	$ (0.78)	$ (0.74)	$ (0.97)
Shares used in computing net loss per share, basic (in shares)	75,786	72,044	66,779
Shares used in computing net loss per share, diluted (in shares)	75,786	72,044	66,779
Product revenue
Revenue:
Total revenue	$ 100,376	$ 99,944	$ 95,416
Costs and expenses:
Cost of revenue	53,315	47,527	45,461
Service revenue
Revenue:
Total revenue	25,917	22,579	21,277
Costs and expenses:
Cost of revenue	7,893	7,291	7,503
Development revenue
Revenue:
Total revenue	2,559	8,865	0
Other revenue
Revenue:
Total revenue	$ 1,729	$ 6,756	$ 550