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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Risks and Uncertainties (Details) - USD ($) $ in Thousands					3 Months Ended	12 Months Ended
	Mar. 02, 2022	Jan. 29, 2021	Dec. 31, 2020	Sep. 10, 2020	Mar. 31, 2022	Dec. 31, 2021
Long-term debt					$ 63,553	$ 48,866
Secured Debt
Long-term debt					50,000
Unsecured Debt
Long-term debt					15,000
Canadian Development Expenses | Los Azules Copper Project
Long-term debt					40,000
Canadian Development Expenses | Equity Financing In February 2021
Gross proceeds						31,500
Canadian Development Expenses | Flow Through Common Shares
Gross proceeds		$ 12,700				$ 12,700
Canadian Exploration Expenditures | Flow Through Common Shares
Gross proceeds	$ 15,100		$ 9,800	$ 10,400	$ 15,100

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