ASSET RETIREMENT AND ENVIRONMENTAL RECLAMATION OBLIGATIONS - Summary (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2024	Dec. 31, 2023
Asset Retirement Obligation and Accrual for Environmental Loss Contingencies [Roll Forward]
Obligations at beginning of period	$ 217,201
Liabilities incurred	3,456
Liabilities settled	(2,450)
Accretion expense	3,597
Total obligations at end of period	221,804
Less current obligations at end of period	(18,822)
Long-term obligations at end of period	$ 202,982	$ 195,566