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NON-CONTROLLING INTERESTS (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended
	Aug. 23, 2021	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Noncontrolling Interest
Net loss		$ (21,064)	$ (12,466)
McEwen Copper
Noncontrolling Interest
Percentage of ownership by noncontrolling shareholders		18.60%
Percentage of ownership by company before private placement		100.00%
Nonredeemable non-controlling interest				$ 14,900
Contributed Surplus				$ 25,100
Sale To Related Parties \| McEwen Copper
Noncontrolling Interest
Sale of flow-through common stock (in shares)	4,000,000
Share price	$ 10.00
Gross proceeds from private placement offering	$ 40,000
Percentage of ownership by noncontrolling shareholders		18.60%
Net loss		$ 1,700