Derivative Instruments and Hedging Activities, Pro Forma Impact - Offsetting Collateral (Details) - USD ($) $ in Millions |
Jun. 30, 2025 |
Dec. 31, 2024 |
|---|---|---|
| Derivative Asset [Abstract] | ||
| Gross collateral | $ 12.4 | $ 46.1 |
| Counterparties with Offsetting Positions or Collateral [Member] | ||
| Derivative Asset [Abstract] | ||
| Gross collateral | 12.4 | 46.1 |
| Current Assets from Risk Management Activities [Member] | ||
| Derivative Asset [Abstract] | ||
| Gross collateral | 14.6 | 37.1 |
| Current Assets from Risk Management Activities [Member] | Counterparties with Offsetting Positions or Collateral [Member] | ||
| Derivative Asset [Abstract] | ||
| Gross collateral | 14.6 | 37.1 |
| Other Long-term Assets [Member] | ||
| Derivative Asset [Abstract] | ||
| Gross collateral | (2.2) | 9.0 |
| Other Long-term Assets [Member] | Counterparties with Offsetting Positions or Collateral [Member] | ||
| Derivative Asset [Abstract] | ||
| Gross collateral | $ (2.2) | $ 9.0 |