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 ($)
MWh
MMBTU
|
Jun. 30, 2025
USD ($)
MMBTU
MWh
|
Jun. 30, 2026
USD ($)
MMBTU
MWh
|
Jun. 30, 2025
USD ($)
MMBTU
MWh
|
|
| Realized gains (losses) | ||||
| Realized gains and losses on derivatives income statement location | Cost of sales | Cost of sales | Cost of sales | Cost of sales |
| Gains (losses) | $ (2.2) | $ 1.7 | $ 8.4 | $ 3.0 |
| Natural gas contracts | ||||
| Realized gains (losses) | ||||
| Gains (losses) | $ (2.6) | $ 0.1 | $ 6.4 | $ 0.8 |
| Notional volumes | ||||
| Notional volumes | MMBTU | 9.5 | 6.5 | 22.9 | 18.8 |
| FTRs | ||||
| Realized gains (losses) | ||||
| Gains (losses) | $ 0.4 | $ 1.6 | $ 2.0 | $ 2.2 |
| Notional volumes | ||||
| Notional volumes | MWh | 1.6 | 1.9 | 3.5 | 4.2 |