Consolidated Statements of Operations (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Revenue and cost of goods sold
Revenue from contract with Customer	$ 192	$ 6,104	$ 5,005	$ 17,565
Other revenue	70	6	116	34
Total revenues	192	6,110	5,005	17,599
Cost of goods sold	2,260	9,893	13,043	27,306
Gross loss	(2,068)	(3,783)	(8,038)	(9,707)
Operating expenses:
Research and development expense	870	1,789	2,127	3,712
Selling, general and administrative expense	3,215	2,431	8,917	6,705
Restructuring expenses	(50)		254
Total operating expenses	4,035	4,220	11,298	10,417
Loss from operations	(6,103)	(8,003)	(19,336)	(20,124)
Other income (expense):
Interest expense	(473)	(605)	(1,559)	(2,127)
(Loss) on modification of 2020 Notes			(726)
(Loss) on conversion of 2020/21 Notes to common stock	(543)		(543)
(Loss) gain from change in fair value of derivative warrant liability		(2)	8	1
Gain (loss) from change in fair value of 2020/21 Notes and 2020 Notes embedded derivative liability	247		(29)	394
Other income (expense)	36	(9)	53	11
Total other income (expense), net	(733)	(616)	(2,796)	(1,721)
Net loss	$ (6,836)	$ (8,619)	$ (22,132)	$ (21,845)
Net loss per share - basic and diluted (in dollars per share)	$ (0.09)	$ (0.66)	$ (0.62)	$ (1.87)
Weighted-average number of common shares outstanding - basic and diluted (in shares)	77,049,896	12,968,265	35,682,794	11,679,530
Ethanol Sales and Related Products [Member]
Revenue and cost of goods sold
Revenue from contract with Customer	$ 21	$ 5,554	$ 3,804	$ 16,184
Total revenues	21	5,554	3,804	16,184
Hydrocarbon [Member]
Revenue and cost of goods sold
Revenue from contract with Customer	101	550	1,085	1,381
Total revenues	$ 101	$ 550	$ 1,085	$ 1,381