Condensed Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Cash flows used in operating activities
Net loss	$ (14,117)	$ (10,851)
Adjustments to reconcile net loss to net cash used in operating activities:
Share-based compensation, net of forfeitures	793	280
Issuance of common stock for services	0	80
Depreciation and amortization	865	831
Long-lived assets impairment	1,614	0
Right of use asset impairment	322	0
Derivative gain	(5,384)	(489)
Changes in operating assets and liabilities:
Decrease (increase) in prepaid expenses and other	366	(703)
(Decrease) increase in accounts payable and accrued expenses	(1,219)	533
Decrease in lease liability	(74)	(66)
Net cash used in operating activities	(16,834)	(10,385)
Cash flows used in investing activities
Purchase of fixed assets	0	(97)
Net cash used in investing activities	0	(97)
Cash flows (used in) provided by financing activities
Proceeds from sale of common stock in connection with the "at-the-market" equity offering program	0	10,512
Costs related to sale of common stock in connection with the "at-the-market" equity offering program	0	(492)
Proceeds from sale of common stock and warrants in connection with the registered direct offering	0	234
Costs related to the sale of common stock and warrants in connection with the registered direct offering	(32)	0
Shares held back in settlement of tax obligation for shares issued in connection with restricted stock awards	(79)	0
Net cash (used in) provided by financing activities	(111)	10,254
Net change in cash and cash equivalents	(16,945)	(228)
Cash and cash equivalents at beginning of period	33,892	17,346
Cash and cash equivalents at end of period	16,947	17,118
Non-cash transactions:
Commercial insurance premium financing agreement	1,159	1,016
Recognition of asset retirement obligation	$ 282	$ 0