OPERATING SEGMENT REPORTING - Geographic information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Revenues from External Customers and Long-Lived Assets
Non-current Assets	$ 572,989		$ 572,989		$ 604,578
Revenue	47,476	$ 34,395	88,704	$ 69,147
Investment in MSC or McEwen Copper	291,319		291,319		326,147
Minera Santa Cruz S.A.
Revenues from External Customers and Long-Lived Assets
Revenue	74,348	67,712	140,274	113,452
USA
Revenues from External Customers and Long-Lived Assets
Non-current Assets	70,267		70,267		71,234
Revenue	29,686	15,971	54,964	27,559
Canada
Revenues from External Customers and Long-Lived Assets
Non-current Assets	80,731		80,731		83,674
Revenue	17,790	$ 18,424	32,540	$ 41,588
Mexico
Revenues from External Customers and Long-Lived Assets
Non-current Assets	31,856		31,856		30,304
Revenue			1,200
Argentina
Revenues from External Customers and Long-Lived Assets
Non-current Assets	390,135		390,135		419,366
Argentina | Minera Santa Cruz S.A.
Revenues from External Customers and Long-Lived Assets
Investment in MSC or McEwen Copper	98,800		98,800		93,200
Argentina | McEwen Copper Inc.
Revenues from External Customers and Long-Lived Assets
Investment in MSC or McEwen Copper	$ 291,300		$ 291,300		$ 326,100