v3.25.2
ACQUISITIONS AND DISPOSITIONS - Impact of Asset Acquisitions (Details)
MW in Millions, $ in Millions
 3 Months Ended
Jun. 30, 2025
USD ($)
MW
Dec. 31, 2024
USD ($)
Asset Acquisition, Contingent Consideration [Line Items]    
Property, Plant and Equipment, Net $ 86,337.1 $ 82,415.6
Operating Lease Assets 580.6 580.1
Asset Retirement Obligations 3,625.1 3,530.6
Regulatory Liabilities and Deferred Investment Tax Credits 7,973.9 8,344.0
Other Current Liabilities 1,356.7 1,490.9
Deferred credits and other noncurrent liabilities 913.8 800.6
PSO    
Asset Acquisition, Contingent Consideration [Line Items]    
Property, Plant and Equipment, Net 8,203.6 6,532.3
Operating Lease Assets 118.6 106.2
Asset Retirement Obligations 133.9 118.8
Regulatory Liabilities and Deferred Investment Tax Credits 698.2 689.7
Other Current Liabilities 78.1 78.6
Deferred credits and other noncurrent liabilities $ 50.3 $ 34.3
PSO | VIU    
Asset Acquisition, Contingent Consideration [Line Items]    
Generation Capacity (MWs) | MW 1,119  
Property, Plant and Equipment, Net $ 1,503.8  
Operating Lease Assets 16.3  
Asset Retirement Obligations 15.5  
Other Liabilities $ 91.4  
Green Country | PSO    
Asset Acquisition, Contingent Consideration [Line Items]    
Generation Capacity (MWs) | MW 795  
Property, Plant and Equipment, Net $ 818.9  
Operating Lease Assets 0.0  
Asset Retirement Obligations 0.0  
Other Liabilities 91.4  
Green Country | PSO | VIU    
Asset Acquisition, Contingent Consideration [Line Items]    
Regulatory Liabilities and Deferred Investment Tax Credits 50.0  
Other Current Liabilities 21.0  
Deferred credits and other noncurrent liabilities $ 20.0  
Pixley | PSO    
Asset Acquisition, Contingent Consideration [Line Items]    
Generation Capacity (MWs) | MW 189  
Property, Plant and Equipment, Net $ 379.6  
Operating Lease Assets 8.9  
Asset Retirement Obligations 12.4  
Other Liabilities $ 0.0  
Flat Ridge IV | PSO    
Asset Acquisition, Contingent Consideration [Line Items]    
Generation Capacity (MWs) | MW 135  
Property, Plant and Equipment, Net $ 305.3  
Operating Lease Assets 7.4  
Asset Retirement Obligations 3.1  
Other Liabilities $ 0.0