Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Cash flows from operating activities:
Net loss	$ (61,376)	$ (8,943)
Adjustments to reconcile net loss to net cash (used for) provided by operating activities:
Depreciation and amortization	3,186	3,750
Change in fair value of warrant	5,278	1,123
Share-based compensation	29,940	0
Asset retirement obligation accretion	130	122
Amortization of intangible	50	51
Amortization of debt issuance costs and discounts	1,696	1,860
Non-cash interest expense	0	33
Bad debt provision	3
Bad debt (recovery)	0	(53)
Other, net	104	0
Changes in operating assets and liabilities:
Trade receivables and other receivables	(409)	4,691
Inventories, net	(1,427)	(1,128)
Prepaid expenses and other current assets	(1,140)	(171)
Accounts payable	11,319	2,943
Accrued expenses	281	1,001
Deferred revenue	(626)	545
Net cash (used for) provided by operating activities	(12,991)	5,824
Cash flows from investing activities:
Capital expenditures	(1,824)	(2,068)
Net cash (used for) investing activities	(1,824)	(2,068)
Cash flows from financing activities:
Proceeds from initial offering of common stock	68,714	0
Proceeds from warrant exercise	116	24
Proceeds from issuance of debt	0	5,000
Payments for deferred financing costs	(4,768)	(610)
Payments for taxes on share-based compensation	(6,027)	0
Net cash provided by financing activities	58,035	4,414
Net increase in cash and cash equivalents	43,220	8,170
Cash and cash equivalents:
Beginning of period	17,379	9,209
End of period	60,599	17,379
Supplemental disclosures of cash flow information:
Cash payments for interest	6,049	5,814
Net increase in capital expenditures included in accounts payable and accrued expenses:	104	20
Net (decrease) increase in offering costs included in accounts payable and accrued expenses	(588)	588
Accrued Series A-2 and A-3 preferred dividends	0	2,480
Accrued withholding tax for share based compensation	2,515	0
Deferred financing costs charged to additional paid in capital	5,232	0
Noncash component of warrants exercised	$ 12,591	$ 0