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LONG-TERM DEBT (Details) - USD ($) $ in Thousands			1 Months Ended	3 Months Ended			9 Months Ended
	Oct. 28, 2019	Aug. 10, 2018	Aug. 31, 2020	Sep. 30, 2020	Dec. 31, 2019	Sep. 30, 2019	Sep. 30, 2019	Sep. 30, 2018	Aug. 10, 2021
LONG-TERM DEBT
Payment of debt issuance costs								$ 908
Scheduled minimum interest payments
2019						$ 1,200	$ 1,200
2020						4,700	4,700
2021						2,000	2,000
Affiliate of Robert McEwen
LONG-TERM DEBT
Debt interest expense						600	1,800	400
Term Loan
LONG-TERM DEBT
Face amount		$ 50,000
Term of debt instrument		3 years
Interest Expense						$ 1,200	3,600	$ 700
Interest costs capitalized							$ 600
Term Loan | Subsequent Event
LONG-TERM DEBT
Term of debt instrument	3 years
Term Loan | Subsequent Event | Minimum
LONG-TERM DEBT
Working capital covenant
Term Loan | Gold Bar Complex
LONG-TERM DEBT
Stated interest rate (as a percent)		9.75%
Term over which monthly payments are made			12 months
Monthly payments			$ 2,000
Final payment									$ 26,000

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