Consolidated Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Revenue	$ 6,426	$ 5,479
Cost of revenue	5,806	5,183
Gross profit	620	296
Operating expenses:
Research and development	9,665	5,125
Selling, general and administrative	12,508	13,666
Total operating expenses	22,173	18,791
Loss from operations	(21,553)	(18,495)
Gain on forgiveness of Paycheck Protection Program loan	1,358	0
Modification of warrants	(373)	(1,838)
Interest expense, net	(1,000)	(910)
Other expense, net	(203)	(289)
Net loss from consolidated companies	(21,771)	(21,532)
Loss from minority interest in limited liability company	(256)	(383)
Comprehensive and net loss	(22,027)	(21,915)
Series B convertible preferred stock dividends	(4,691)	(4,149)
Net loss attributable to common stockholders	$ (26,718)	$ (26,064)
Net loss per share of common stock:
Basic and diluted (in dollars per share)	$ (2.65)	$ (16.56)
Weighted average shares used in computing net loss per common share:
Basic and diluted (in shares)	10,089,722	1,573,528