Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Cash flows from operating activities:
Net loss	$ (66,246)	$ (61,376)
Adjustments to reconcile net loss to net cash (used for) operating activities:
Depreciation and amortization	2,905	3,236
Change in fair value of warrant	0	5,278
Share-based compensation	7,071	29,940
Amortization of debt issuance costs and discounts	1,929	1,696
Loss on extinguishment of debt	4,896	0
All other non-cash expenses	359	237
Changes in operating assets and liabilities:
Trade receivables and other receivables, net	(6,815)	(409)
Inventories	2,582	(1,427)
Prepaid expenses and other current assets	(1,366)	(1,140)
Accounts payable	(7,872)	11,319
Accrued expenses	746	281
Deferred revenue	1,601	(626)
Net cash used for operating activities	(60,210)	(12,991)
Cash flows from investing activities:
Capital expenditures	(663)	(1,824)
Net cash (used for) investing activities	(663)	(1,824)
Cash flows from financing activities:
Proceeds from issuance of common stock and warrant exercises	39,317	68,830
Proceeds from issuance of debt	70,000	0
Debt repayment	(50,000)	0
Payments for financing costs	(3,946)	(4,768)
Premium paid to retire debt	(2,944)	0
Payments for taxes on share-based compensation	(2,827)	(6,027)
Net cash provided by financing activities	49,600	58,035
Net (decrease)/increase in cash and cash equivalents	(11,273)	43,220
Cash and cash equivalents:
Beginning of period	60,599	17,379
End of period	49,326	60,599
Supplemental disclosures of cash flow information:
Cash payments for interest	7,340	6,049
Net increase in capital expenditures included in accounts payable and accrued expenses	104	104
Net (decrease) increase in offering costs included in accounts payable and accrued expenses	0	(588)
Accrued withholding tax for share based compensation	0	2,515
Deferred financing costs charged to additional paid in capital	540	5,232
Warrants issued in connection with long-term debt	6,800	0
Noncash component of warrants exercised	$ 0	$ 12,952