Defined Benefit and Postretirement Benefits (Components Of Net Periodic Cost) (Detail) - USD ($) $ in Millions |
3 Months Ended | |
|---|---|---|
Mar. 31, 2026 |
Mar. 31, 2025 |
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| Pension | ||
| Defined Benefit Plan Disclosure [Line Items] | ||
| Service cost | $ 0.8 | $ 0.8 |
| Interest cost | 8.1 | 8.6 |
| Expected return on plan assets | (10.9) | (11.0) |
| Amortization of prior service cost | 0.2 | 0.2 |
| Amortization of net loss (gain) | 3.1 | 3.5 |
| Net periodic loss (benefit) | 1.3 | 2.1 |
| Postretirement | ||
| Defined Benefit Plan Disclosure [Line Items] | ||
| Service cost | 0.0 | 0.0 |
| Interest cost | 0.1 | 0.0 |
| Expected return on plan assets | 0.0 | 0.0 |
| Amortization of prior service cost | 0.0 | 0.0 |
| Amortization of net loss (gain) | (0.1) | (0.1) |
| Net periodic loss (benefit) | $ 0.0 | $ (0.1) |
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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 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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