Quarterly report [Sections 13 or 15(d)]

COMMITMENTS AND CONTINGENCIES (Details)

v3.25.3
COMMITMENTS AND CONTINGENCIES (Details)
$ in Millions
9 Months Ended
Jun. 30, 2025
USD ($)
item
Nov. 08, 2024
USD ($)
Oct. 21, 2024
USD ($)
Oct. 09, 2024
USD ($)
Sep. 30, 2025
USD ($)
Jun. 15, 2025
USD ($)
Dec. 31, 2010
USD ($)
COMMITMENTS AND CONTINGENCIES              
Additional royalty due to disallowed deductions         $ 4.7   $ 4.7
Accrued Royalties         5.0    
Estimated penalties         0.3    
Decommissioning obligations         1.7    
Increase in decommissioning obligation accrual         13.7    
Accrual for decommissioning obligations         $ 34.5    
Withdrawal in collateral demands           $ 94.0  
The Sureties              
COMMITMENTS AND CONTINGENCIES              
Cash collateral   $ 183.0          
Philadelphia Indemnity Insurance Company              
COMMITMENTS AND CONTINGENCIES              
Surety bonds issued   71.0          
The Sureties and PIIC              
COMMITMENTS AND CONTINGENCIES              
Cash collateral   254.0          
Surety Bonds              
COMMITMENTS AND CONTINGENCIES              
Surety bonds issued     $ 111.0 $ 55.0      
Cancelled bonds       13.1      
Cash collateral     $ 23.0 $ 55.0      
Surety Bonds | The Sureties              
COMMITMENTS AND CONTINGENCIES              
Surety providers | item 2            
Surety bonds issued $ 105.0            
Surety Bonds | Applied litigation              
COMMITMENTS AND CONTINGENCIES              
Surety bonds issued   11.3          
Cash collateral   11.3          
Unpaid in loss contingency   0.4          
Surety Bonds | U.S. Fire Litigation              
COMMITMENTS AND CONTINGENCIES              
Surety bonds issued   93.5          
Cash collateral   $ 93.5