STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Cash flows from operating activities:
Net loss	$ (78,751)	$ (79,976)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation	2,597	1,128
Impairments	740	0
Amortization of financing costs	383	0
Stock-based compensation	10,774	6,829
(Increase) decrease in:
Receivables	3,555	(1,335)
Prepaid expenses and other current assets	(9,189)	(11,566)
Right of use assets	(352)	(2,378)
Other noncurrent assets	201	(635)
Increase (decrease) in:
Accounts payable	274	54
Accrued expenses	(10,512)	5,272
Lease liabilities	434	2,462
Net cash used in operating activities	(61,468)	(57,013)
Cash flows from investing activities:
Purchases of property and equipment	(3,323)	(9,778)
Net cash used in investing activities	(3,323)	(9,778)
Cash flows from financing activities:
Proceeds from Issuance of Long-term Debt	25,000	0
Payment of debt issuance cost	(260)	0
Proceeds from exercise of stock options	1,036	442
Issuance of common stock in connection with a public offering, net	0	88,661
Issuance of common stock in connection with an at the market offering, net	0	13,016
Net cash provided by financing activities	25,776	102,119
Net decrease in cash and cash equivalents, and restricted cash	(39,015)	35,328
Cash and cash equivalents, and restricted cash, beginning of period	115,069	79,741
Cash and cash equivalents, and restricted cash, end of period	76,054	115,069
Supplementary disclosure of cash flow information:
Cash paid for interest	630	0
Amounts included in accrued expenses and accounts payable related to property and equipment	134	471
Supplementary disclosure of noncash investing and financing activities:
Warrants issued with long-term debt	$ 1,016	$ 0