ASSET RETIREMENT OBLIGATIONS - Activity (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Asset retirement and mine closing liability
Balance at the beginning of the period	$ 131,099	$ 127,898
Accretion expense	3,731	3,688
Payments	(2,445)	(1,383)
Allocation of liability associated with mine development and change in assumptions	17,428	896
Balance at the end of the period	$ 149,813	$ 131,099