OPERATING SEGMENT REPORTING - Geographic information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Revenues from External Customers and Long-Lived Assets
Non-current Assets	$ 608,220		$ 608,220		$ 604,578
Revenue	52,250	$ 38,404	140,954	$ 107,551
Investment in MSC or McEwen Copper	303,467		303,467		326,147
Minera Santa Cruz S.A.
Revenues from External Customers and Long-Lived Assets
Revenue	70,361	64,495	210,635	177,947
USA
Revenues from External Customers and Long-Lived Assets
Non-current Assets	90,059		90,059		71,234
Revenue	33,251	17,967	88,215	45,526
Canada
Revenues from External Customers and Long-Lived Assets
Non-current Assets	84,763		84,763		83,674
Revenue	18,999	20,259	51,539	61,847
Mexico
Revenues from External Customers and Long-Lived Assets
Non-current Assets	32,345		32,345		30,304
Revenue		$ 178	1,200	$ 178
Argentina
Revenues from External Customers and Long-Lived Assets
Non-current Assets	401,053		401,053		419,366
Argentina | Minera Santa Cruz S.A.
Revenues from External Customers and Long-Lived Assets
Investment in MSC or McEwen Copper	97,600		97,600		93,200
Argentina | McEwen Copper Inc.
Revenues from External Customers and Long-Lived Assets
Investment in MSC or McEwen Copper	$ 303,500		$ 303,500		$ 326,100