v3.26.1
ASSET RETIREMENT AND ENVIRONMENTAL REMEDIATION OBLIGATIONS (Tables)
3 Months Ended
Mar. 31, 2026
Asset Retirement Obligation And Accrual For Environmental Loss Contingencies Disclosure [Abstract]  
Schedule of Asset Retirement Obligations and Environmental Remediation Obligations
Aggregate carrying amounts of asset retirement obligations and environmental remediation obligations are as follows (dollars in thousands):
Three Months Ended March 31, 2026
Obligations at beginning of period$336,768 
Liabilities settled(7,038)
Accretion expense951 
Change in estimate4,233 
Total obligations at end of period$334,914 
Less current obligations at end of period(143,798)
Long-term obligations at end of period$191,116