v3.26.1
ASSET RETIREMENT AND ENVIRONMENTAL REMEDIATION OBLIGATIONS - Narrative (Details)
$ in Millions
3 Months Ended
Mar. 31, 2026
USD ($)
Asset Retirement Obligation And Accrual For Environmental Loss Contingencies [Line Items]  
Environmental Loss Contingency, Statement Of Financial Position, Extensible Enumeration, Not Disclosed Flag environmental remediation liability
New Horizon Mine  
Asset Retirement Obligation And Accrual For Environmental Loss Contingencies [Line Items]  
Environmental reclamation obligations $ 66.0
Discounted basis of environmental reclamation obligation $ 24.7
Discount rate of environmental reclamation obligations (as a percent) 6.73%
Undiscounted future cash outflows of environmental reclamation obligations $ 36.6