Employee Benefits - Components of Net Periodic Benefit Cost (Details) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2025 |
Sep. 30, 2024 |
Sep. 30, 2025 |
Sep. 30, 2024 |
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| Retirement Plans | ||||
| Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract] | ||||
| Service cost | $ 0.5 | $ 0.5 | $ 1.4 | $ 1.5 |
| Interest cost | 1.0 | 1.0 | 2.9 | 3.0 |
| Expected return on plan assets | (1.1) | (0.8) | (3.2) | (2.8) |
| Amortization of unrecognized net loss | 0.0 | 0.1 | 0.1 | 0.5 |
| Settlement charge | 0.2 | 0.2 | 0.7 | 0.6 |
| Regulatory asset decrease | 0.3 | 0.0 | 0.4 | 0.0 |
| Net periodic benefit cost (credit) | 0.9 | 1.0 | 2.3 | 2.8 |
| PBOP | ||||
| Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract] | ||||
| Service cost | 0.0 | 0.0 | 0.0 | 0.0 |
| Interest cost | 0.3 | 0.3 | 0.9 | 0.9 |
| Expected return on plan assets | (0.7) | (0.7) | (2.1) | (2.0) |
| Amortization of unrecognized net loss | 0.0 | 0.0 | 0.0 | 0.0 |
| Settlement charge | 0.0 | 0.0 | 0.0 | 0.0 |
| Regulatory asset decrease | 0.0 | 0.0 | 0.0 | 0.0 |
| Net periodic benefit cost (credit) | $ (0.4) | $ (0.4) | $ (1.2) | $ (1.1) |
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- Definition The (reduction to expense) expense charged against earnings during the period to meet the previously settled rate case pension cost regulatory requirement. No definition available.
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- Definition Amount of gain (loss) recognized in net periodic benefit (cost) credit of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of expected return (loss) recognized in net periodic benefit (cost) credit, calculated based on expected long-term rate of return and market-related value of plan assets of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of cost recognized for passage of time related to defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of net periodic benefit cost (credit) for defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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- Definition Amount of gain (loss) recognized in net periodic benefit (cost) credit from irrevocable action relieving primary responsibility for benefit obligation and eliminating risk related to obligation and assets used to effect settlement. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of cost for actuarial present value of benefits attributed to service rendered by employee for defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Details
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- Details
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