Pension and Postretirement Benefit Costs - Schedule of Net Periodic Benefit (Benefit) Cost (Details) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2026 |
Jun. 30, 2025 |
Jun. 30, 2026 |
Jun. 30, 2025 |
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| Defined Benefit Plan Disclosure [Line Items] | ||||
| Net periodic postretirement benefit credit | $ (0.3) | $ (7.4) | $ (0.7) | $ (14.8) |
| Postretirement benefit plans | ||||
| Defined Benefit Plan Disclosure [Line Items] | ||||
| Service cost for benefits earned | 0.1 | 0.1 | 0.1 | 0.2 |
| Interest cost on accumulated postretirement benefit obligation | 1.7 | 1.9 | 3.3 | 3.9 |
| Expected return on plan assets | (0.1) | (0.1) | (0.1) | (0.2) |
| Amortization of prior service credit | (2.9) | (10.2) | (5.7) | (20.4) |
| Net periodic postretirement benefit credit | $ (1.2) | $ (8.3) | $ (2.4) | $ (16.5) |
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- Definition Amount of prior service cost (credit) 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 Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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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- 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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