DERIVATIVE INSTRUMENTS - GAINS (LOSSES) AND NOTIONAL VOLUMES (Details) MWh in Millions, MMBTU in Millions, $ in Millions |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
|
Sep. 30, 2026
USD ($)
MMBTU
MWh
|
Sep. 30, 2025
USD ($)
MMBTU
MWh
|
Sep. 30, 2026
USD ($)
MMBTU
MWh
|
Sep. 30, 2025
USD ($)
MWh
MMBTU
|
|
| 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) | $ (4.4) | $ 0.3 | $ 4.0 | $ 3.3 |
| Natural gas contracts | ||||
| Realized gains (losses) | ||||
| Gains (losses) | $ (4.5) | $ (2.9) | $ 1.9 | $ (2.1) |
| Notional volumes | ||||
| Notional volumes | MMBTU | 8.3 | 7.4 | 31.2 | 26.2 |
| FTRs | ||||
| Realized gains (losses) | ||||
| Gains (losses) | $ 0.1 | $ 3.2 | $ 2.1 | $ 5.4 |
| Notional volumes | ||||
| Notional volumes | MWh | 2.1 | 2.1 | 5.6 | 6.3 |