Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended		12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Cash flows from operating activities
Net loss	$ (51,651)	$ (59,719)
Adjustments to reconcile net loss to net cash used in operating activities:
Non-cash other income/expense, net	(19)	(49)
Non-cash interest income	1	24
Non-cash interest expense	351	379
Loss on extinguishment of debt	2,757
Depreciation and amortization expense	315	162
Amortization of right-of-use assets	260	291
Stock-based compensation	4,266	7,866
Deferred income taxes		(5)
Other, net	(66)
Changes in operating assets and liabilities:
Increase/(decrease) in long-term receivables		(288)
Increase/(decrease) in accounts receivable, net and other receivables and prepaid expenses	(3,237)	(1,258)
Increase/(decrease) in inventory	(5,121)	(162)
Increase/(decrease) in accounts payable	(2,529)	(39)
Decrease in accrued expenses and other liabilities	(3,103)	(3,553)
Increase/(decrease) in other non-current assets	9
Increase/(decrease) in other non-current liabilities	(156)	(88)
Increase/(decrease) in income tax liabilities	(44)	34
Net cash used in operating activities	(57,967)	(56,405)
Cash flows from investing activities
Purchases of plant and equipment and intangible assets	(95)	(97)
Deposits into employee stock purchase plan restricted cash accounts		228
Changes in restricted cash	(162)
Net cash used in investing activities	(257)	131
Cash flows from financing activities
Proceeds from exercise of warrants	665
Proceeds from issuance of common stock and warrants associated with May 2020 financing	38,414
Proceeds from at-the-market facility	7,119	23,189
Proceeds from long-term debt, net of issuance costs		9,980
Proceeds from employee stock purchase plan	43	170
Repayments of long-term borrowings	(30,000)
Equity transaction costs	(3,338)	(659)
Net cash provided by financing activities	12,903	32,680
Effects of exchange rate changes on the balance of cash and cash equivalents held in foreign currencies	262	(80)
Net decrease in cash, cash equivalents and restricted cash	(45,059)	(23,674)
Cash, cash equivalents and restricted cash at beginning of period	86,411	102,003	$ 102,003
Cash, cash equivalents and restricted cash at end of period	41,352	78,329	$ 86,411
Supplemental disclosure of cash flow information:
Interest paid	1,273	1,735
Equity transaction costs included in accounts payable and accrued expenses	$ 564	$ 382