Risk Management Activities (Schedule of Gains (Losses) on Commodity Price Risk Programs) (Details) - USD ($) $ in Millions |
Jun. 30, 2025 |
Dec. 31, 2024 |
|---|---|---|
| Deferred Derivative Gain (Loss) | ||
| Derivative Instruments, Gain (Loss) [Line Items] | ||
| Regulatory Liabilities | $ 40.1 | $ 28.7 |
| Deferred Derivative Gain (Loss) | ||
| Derivative Instruments, Gain (Loss) [Line Items] | ||
| Regulatory Assets | $ 6.9 | $ 6.5 |