CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Cash flows from operating activities:
Net loss	$ (18,115)	$ (85,330)
Adjustments to reconcile net loss for the period to net cash used in operating activities:
Non-cash portion of interest expense - Note 9	9,215	30,376
Non-cash (gain) loss on fair value adjustment for warrant liabilities - Note 11	(10,144)	922
Write-down of production inventories - Note 4	0	17,924
Depreciation and amortization	3,102	2,753
Stock-based compensation - Note 14	1,586	592
Accretion - Note 12	204	187
Phantom share compensation	0	225
Changes in operating assets and liabilities:
Accounts receivable	(1,037)	(275)
Production-related inventories, current and non-current	(6,285)	(24,787)
Materials and supplies inventories	(762)	(2,484)
Prepaids and other assets, current and non-current	(3,045)	(4,766)
Accounts payable and accrued expenses	3,010	7,807
Other liabilities, current and non-current	954	(786)
Net cash used in operating activities	(21,317)	(57,642)
Cash flows used in investing activities:
Additions to plant, equipment, and mine development	(9,065)	(11,704)
Net cash used in investing activities	(9,065)	(11,704)
Cash flows from financing activities:
Principal payments on debt	(583)	0
Proceeds from Sprott Royalty Obligation - Note 10	0	30,000
Proceeds from Recapitalization Transaction	0	10,419
Transaction and issuance costs	0	(15,138)
Net cash (used in) provided by financing activities	(583)	107,303
Net (decrease) increase in cash and restricted cash	(30,965)	37,957
Cash and restricted cash, beginning of period	96,040	48,967
Cash and restricted cash, end of period	65,075	86,924
Reconciliation of cash and restricted cash:
Cash	30,220	47,293
Restricted cash - non-current	34,855	39,631
Total cash and restricted cash	65,075	86,924
Sprott Credit Agreement
Cash flows from financing activities:
Proceeds from issuance of debt	0	68,600
The 1.25 Lien Notes
Cash flows from financing activities:
Proceeds from issuance of debt	0	44,841
First Lien Agreement
Cash flows from financing activities:
Repayment of debt	0	(125,468)
Promissory Note
Cash flows from financing activities:
Repayment of debt	0	(6,914)
Private Placement
Cash flows from financing activities:
Proceeds from issuance of equity	0	75,963
Forward purchase contract
Cash flows from financing activities:
Proceeds from issuance of equity	$ 0	$ 25,000