Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 20,914	$ 60,599
Trade and other receivables, net	10,316	6,481
Inventories, net	4,124	5,441
Prepaid expenses and other current assets	2,706	1,680
Total current assets	38,060	74,201
Property and equipment, net	10,351	12,207
Intangible assets, net	165	204
Other assets	242	239
Total assets	48,818	86,851
Current liabilities:
Accounts payable and accrued expenses	19,218	27,631
Deferred revenue, current	835	721
Loans payable, current	0	4,600
Total current liabilities	20,053	32,952
Loans payable, net	59,775	42,603
Deferred revenue, net of current portion	2,127	0
Asset retirement obligations	1,322	1,216
Total liabilities	83,277	76,771
Commitments and contingencies (note 17)
Stockholders' (deficit)/equity:
Common stock, $.001 par value. Authorized 250,000,000 shares; 25,042,964 and 24,957,309 shares issued and outstanding at September 30, 2019 and December 31, 2018, respectively	25	25
Additional paid-in capital	83,354	71,431
Accumulated deficit	(117,838)	(61,376)
Total stockholders' (deficit)/equity	(34,459)	10,080
Total liabilities and stockholders' (deficit)/equity	$ 48,818	$ 86,851