ASSET RETIREMENT AND ENVIRONMENTAL RECLAMATION OBLIGATIONS - Summary (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 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	(752)
Accretion expense	1,790
Total obligations at end of period	221,695
Less current obligations at end of period	(19,783)
Long-term obligations at end of period	$ 201,912	$ 195,566