v3.26.1
DERIVATIVE INSTRUMENTS - GAINS (LOSSES) AND NOTIONAL VOLUMES (Details)
MWh in Millions, MMBTU in Millions, $ in Millions
3 Months Ended 6 Months Ended
Jun. 30, 2026
USD ($)
MWh
MMBTU
Jun. 30, 2025
USD ($)
MWh
MMBTU
Jun. 30, 2026
USD ($)
MWh
MMBTU
Jun. 30, 2025
USD ($)
MWh
MMBTU
Realized gains and losses        
Gains (losses) $ (12.5) $ 9.8 $ 18.9 $ 9.4
Natural gas contracts | Utility operations        
Realized gains and losses        
Gains (losses) $ (16.8) $ 6.5 $ 12.8 $ 4.6
Realized gains and losses on derivatives income statement location Cost of sales Cost of sales Cost of sales Cost of sales
Notional volumes        
Notional volumes | MMBTU 48.6 47.3 111.6 108.8
FTRs and TCRs | Non-Utility Energy Infrastructure        
Realized gains and losses        
Gains (losses) $ 0.0 $ 0.3 $ 0.1 $ 0.1
Realized gains and losses on derivatives income statement location Total operating revenues Total operating revenues Total operating revenues Total operating revenues
Notional volumes        
Notional volumes | MWh 0.0 0.3 0.1 0.6
FTRs and TCRs | Utility operations        
Realized gains and losses        
Gains (losses) $ 4.3 $ 3.0 $ 6.0 $ 4.7
Realized gains and losses on derivatives income statement location Cost of sales Cost of sales Cost of sales Cost of sales
Notional volumes        
Notional volumes | MWh 6.1 6.7 11.9 13.8