Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Operating activities:
Net loss	$ (41,594)	$ (35,415)
Adjustments to reconcile net loss to net cash used for operating activities:
Depreciation, amortization, and impairment	2,233	2,337
Share-based compensation	5,128	5,052
Amortization of debt issuance costs and discounts	3,604	1,758
Interest expense related to the sale of future revenue, net	10,457	0
Other, net	(248)	34
Changes in operating assets and liabilities:
Trade and other receivables, net	(6,726)	5,082
Inventories, net	(402)	(383)
Prepaid expenses and other assets	1,793	(7,101)
Accounts payable	(874)	(3,189)
Accrued expenses and other liabilities	(2,046)	616
Deferred revenue	3,757	(738)
Net cash used for operating activities	(24,918)	(31,947)
Investing activities:
Capital expenditures	(380)	(281)
Net cash used for investing activities	(380)	(281)
Financing activities:
Proceeds from issuance of common stock, net	24,592	0
Proceeds from shares issued under employee stock purchase plan	76	62
Payments for taxes on share-based compensation	(13)	(96)
Net cash provided by/(used for) financing activities	24,655	(34)
Net decrease in cash and cash equivalents	(643)	(32,262)
Cash and cash equivalents at beginning of period	31,807	49,326
Cash and cash equivalents at end of period	31,164	17,064
Supplemental disclosures of cash flow information:
Cash payments for interest	$ 4,828	$ 6,562