EQUITY METHOD INVESTMENTS - Summary of the operating results of McEwen Copper (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
EQUITY METHOD INVESTMENTS
Advanced projects	$ (1,684)	$ (2,454)
Interest and other income	(1,286)	(870)
Loss before income and mining taxes	(7,349)	(22,940)
Loss from investment in McEwen Copper	$ (8,068)	$ (16,734)
McEwen Copper
EQUITY METHOD INVESTMENTS
Subsidiary (as a percent)	100.00%	100.00%
Advanced projects	$ (21,271)	$ (48,183)
Other expenses	(1,097)	(2,016)
Foreign exchange loss	(9)	(3,992)
Interest and other income	3,906	16,454
Loss before income and mining taxes	(18,471)	(37,737)
Net (loss) income and comprehensive (loss) income attributable to McEwen shareholders	(18,471)	(37,737)
Loss from investment in McEwen Copper	$ (8,578)	$ (18,012)

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