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SIGNIFICANT ACCOUNTING POLICIES - Risks and Uncertainties (Details) - USD ($) $ in Millions					6 Months Ended	12 Months Ended
	Feb. 09, 2021	Jan. 29, 2021	Dec. 31, 2020	Sep. 10, 2020	Jun. 30, 2021	Dec. 31, 2020
Equity Financing In February 2021
Gross proceeds	$ 31.5				$ 31.5
Canadian Development Expenses | Flow Through Common Shares
Gross proceeds		$ 12.7			$ 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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