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DEBT (Details) - USD ($) |  |  |  |  | 1 Months Ended | 3 Months Ended | 6 Months Ended | 9 Months Ended |
--- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Jun. 25, 2020 | May 23, 2019 | Mar. 29, 2019 | Aug. 10, 2018 | Mar. 31, 2021 | Sep. 30, 2022 | Jun. 30, 2022 | Mar. 31, 2022 | Jun. 30, 2020 | Sep. 30, 2020 | Sep. 30, 2019 | Dec. 31, 2019
LONG-TERM DEBT |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt from related party |  |  |  |  |  |  |  |  |  | $ 23,997,000 |  | $ 19,758,000
Shares issued as bonus interest |  | 1,935,484 | 14,193,548 |  |  |  |  |  |  |  |  |
Stock issued during the period |  | $ 2,600,000 | $ 20,300,000 |  |  |  |  |  |  |  |  |
Reduction of minimum working capital covenant |  |  |  |  |  |  |  |  | $ 10,000,000.0 |  |  |
Gold Bar mine | Construction in Process |  |  |  |  |  |  |  |  |  |  |  |
LONG-TERM DEBT |  |  |  |  |  |  |  |  |  |  |  |
Interest costs capitalized |  |  |  |  |  |  |  |  |  |  | $ 600,000 |
Affiliate of Robert McEwen |  |  |  |  |  |  |  |  |  |  |  |
LONG-TERM DEBT |  |  |  |  |  |  |  |  |  |  |  |
Shares issued as bonus interest |  |  |  |  |  |  |  |  |  | 1,045,850 |  |
Stock issued during the period |  |  |  |  |  |  |  |  |  | $ 900,000 |  |
Term Loan | Robert McEwen |  |  |  |  |  |  |  |  |  |  |  |
LONG-TERM DEBT |  |  |  |  |  |  |  |  |  |  |  |
Face amount |  |  |  | $ 50,000,000.0 |  |  |  |  |  |  |  |
Term of debt instrument |  |  |  | 3 years |  |  |  |  |  |  |  |
Long-term debt from related party |  |  |  | $ 25,000,000.0 |  |  |  |  |  |  |  |
Stated interest rate (as a percent) |  |  |  | 9.75% |  |  |  |  |  |  |  |
Amended loan agreement |  |  |  |  |  |  |  |  |  |  |  |
LONG-TERM DEBT |  |  |  |  |  |  |  |  |  |  |  |
Face amount | $ 50,000,000 |  |  |  |  |  |  |  |  |  |  |
Principal repayments | $ 2,000,000.0 |  |  |  |  |  |  |  |  |  |  |
Term loan retirement period | 12 months |  |  |  |  |  |  |  |  |  |  |
Final payment | $ 26,000,000.0 |  |  |  |  |  |  |  |  |  |  |
Extension term for repayment of debt | 2 years |  |  |  |  |  |  |  |  |  |  |
Shares issued as bonus interest | 2,091,700 |  |  |  |  |  |  |  |  |  |  |
Stock issued during the period | $ 1,875,000 |  |  |  |  |  |  |  |  |  |  |
Reduction of minimum working capital covenant |  |  |  |  | $ 2,500,000 |  |  |  | $ 10,000,000.0 |  |  |
Increase in working capital covenant |  |  |  |  |  | $ 10,000,000 | $ 7,000,000.0 | $ 5,000,000.0 |  |  |  |

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