v3.25.4

Retirement Plans - Components of Net Pension Plan Expense (Income) (Detail) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023
Defined Benefit Plan Disclosure [Line Items] |  |  |
Interest cost | $ 8.0 | $ 11.1 | $ 11.7
Expected return on assets | $ (6.8) | $ (13.5) | $ (13.2)
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) Excluding Service Cost, Statement of Income or Comprehensive Income [Extensible Enumeration] | Other Nonoperating Income (Expense) | Other Nonoperating Income (Expense) | Other Nonoperating Income (Expense)
Amortization, net | $ 1.2 | $ 1.3 | $ 1.0
Net pension plan expense (income) | 2.4 | (1.1) | (0.5)
Pension plan settlement charge | 82.8 | 0.0 | 0.0
Total pension plan expense (income) | $ 85.2 | $ (1.1) | $ (0.5)
Weighted-average assumptions used to calculate total pension plan expense (income): |  |  |
Discount rate | 5.30% | 5.00% | 5.20%
Expected return on plan assets | 5.30% | 6.00% | 5.80%

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