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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Risks and Uncertainties (Details) - USD ($) $ in Millions						3 Months Ended
	Mar. 29, 2021	Feb. 09, 2021	Jan. 29, 2021	Dec. 31, 2020	Sep. 10, 2020	Mar. 31, 2021
Duration of agreement reached to provide additional support to communities and greater long-term certainty for El Gallo project	10 years
Equity Financing In February 2021
Gross proceeds		$ 31.5
Canadian Development Expenses | Flow Through Common Shares
Gross proceeds			$ 12.7
Canadian Exploration Expenditures
Gross proceeds						$ 20.2
Canadian Exploration Expenditures | Flow Through Common Shares
Gross proceeds				$ 9.8	$ 10.4

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