CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Cash flows used in operating activities:
Net loss	$ (15,849)	$ (23,213)	$ (46,891)	$ (41,328)
Adjustments to reconcile net loss for the period to net cash used in operating activities:
Non-cash portion of interest expense - Note 10			10,129	13,042
Non-cash loss (gain) on fair value adjustment for warrant liabilities - Note 12	(1,133)	(812)	482	(10,956)
Depreciation and amortization			2,577	5,175
Stock-based compensation			1,750	2,227
Write-off of deposit	0	916	0	916
Accretion - Note 13	102	102	306	306
Gain on sale of equipment	(211)	0	(813)	0
Changes in operating assets and liabilities:
Accounts receivable			(978)	79
Income tax receivable			0	(95)
Interest receivable			(294)	0
Production-related inventories			8,632	5,351
Materials and supplies inventories			235	(1,141)
Prepaids and deposits			(1,880)	(1,634)
Accounts payable			(3,835)	(1,852)
Contract liabilities - Notes 8 and 15			6,682	1,598
Other liabilities			(1,401)	1,262
Net cash used in operating activities			(25,299)	(27,050)
Cash flows provided by (used in) investing activities:
Additions to plant, equipment, and mine development			(913)	(11,908)
Proceeds from sale of equipment - Note 5			2,007	0
Proceeds from assets held for sale - Note 7			1,375	0
Net cash provided by (used in) investing activities			2,469	(11,908)
Cash flows provided by (used in) financing activities:
Principal payments on debt			(25,506)	(2,978)
Principal payments on notes payable			(94)	(58)
Proceeds from issuance of common stock and warrants, net of issuance costs			188,860	0
Net cash provided by (used in) financing activities			163,260	(3,036)
Net increase (decrease) in cash, cash equivalents, and restricted cash			140,430	(41,994)
Cash, cash equivalents, and restricted cash, beginning of period			46,635	96,040
Cash, cash equivalents, and restricted cash, end of period	187,065	54,046	187,065	54,046
Reconciliation of cash, cash equivalents, and restricted cash:
Cash and cash equivalents	153,403	19,753	153,403	19,753
Restricted cash	33,662	34,293	33,662	34,293
Total cash, cash equivalents, and restricted cash	$ 187,065	$ 54,046	$ 187,065	$ 54,046