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v3.25.4

Pension and Post-Employment Benefits - Defined Benefit Pension Plan (Detail) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023
Plan net pension (credit)/charge: |  |  |
Pension scheme settlement |  | $ 92.4 |
Other Nonoperating Income (Expense), Total | $ (0.6) | 9.6 | $ 10.5
One Time pension scheme settlement charge | 0.0 | $ 155.6 | $ 0.0
United Kingdom Plan [Member] |  |  |
Plan assumptions at December 31, (%): |  |  |
Discount rate |  | 5.18% | 4.59%
Inflation rate |  | 2.85% | 2.70%
Rate of return on plan assets - overall on bid-value |  | 4.20% | 4.25%
Plan asset allocation by category (%): |  |  |
Total plan asset allocation by category |  | 100.00% | 100.00%
United Kingdom Plan [Member] | Cash [Member] |  |  |
Plan asset allocation by category (%): |  |  |
Total plan asset allocation by category |  | 100.00% | 4.00%
United Kingdom Plan [Member] | Defined Benefit Plan Debt Securities And Insurance Contracts [Member] |  |  |
Plan asset allocation by category (%): |  |  |
Total plan asset allocation by category |  | 0.00% | 96.00%
United Kingdom [Member] | United Kingdom Plan [Member] |  |  |
Plan net pension (credit)/charge: |  |  |
Service cost/(credit) | 1.5 | $ (4.9) | $ 3.4
Interest cost on PBO | 0.0 | 18.6 | 19.6
Expected return on plan assets | 0.0 | (25.9) | (25.2)
Amortization of prior service cost | 0.0 | 16.8 | 0.5
Amortization of actuarial net losses | 0.0 | 0.0 | (1.6)
Recycling of residual reserves | 0.0 | 138.8 | 0.0
Net periodic cost/(benefit) | 1.5 | 143.4 | (3.3)
Pension scheme settlement charge | 0.0 | 155.6 | 0.0
Release of historic cumulative translation adjustments | 0.0 | (0.7) | 0.0
Pension scheme settlement | 0.0 | 138.1 | 0.0
Tax relating to the recycling of residual reserves | 0.0 | (34.7) | 0.0
Tax relating to historic cumulative translation adjustments | 0.0 | (11.0) | 0.0
Pension scheme settlement | $ 0.0 | $ 92.4 | $ 0.0
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Interest Cost, Statement of Income or Comprehensive Income [Extensible Enumeration] | Other Nonoperating Income (Expense), Total | Other Nonoperating Income (Expense), Total | Other Nonoperating Income (Expense), Total
Defined Benefit Plan, Net Periodic Benefit (Cost) Credit, Expected Return (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Other Nonoperating Income (Expense), Total | Other Nonoperating Income (Expense), Total | Other Nonoperating Income (Expense), Total
Defined Benefit Plan, Net Periodic Benefit (Cost) Credit, Amortization of Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Other Nonoperating Income (Expense), Total |  |
Other Nonoperating Income (Expense), Total | $ 0.0 | $ (7.3) | $ (6.7)
One Time pension scheme settlement charge | 0.0 | 116.7 | 0.0
United Kingdom [Member] | United Kingdom Plan [Member] | Selling General And Administrative Expenses [Member] |  |  |
Plan net pension (credit)/charge: |  |  |
Service cost/(credit) | 1.5 | (4.9) | 3.4
United Kingdom [Member] | United Kingdom Plan [Member] | Other Nonoperating Income (Expense) [Member] |  |  |
Plan net pension (credit)/charge: |  |  |
Amortization of prior service cost | 0.0 | 0.0 | 0.5
United Kingdom [Member] | United Kingdom Plan [Member] | Pension Scheme Settlement Charge [Member] |  |  |
Plan net pension (credit)/charge: |  |  |
Amortization of prior service cost | 0.0 | 16.8 | 0.0
Recycling of residual reserves | 0.0 | 138.8 | 0.0
Tax relating to the amortization of prior service cost | 0.0 | (4.2) | 0.0
Tax relating to the recycling of residual reserves | (0.0) | (34.7) | 0.0
United Kingdom [Member] | Reclassification Out of Accumulated Other Comprehensive Income/(Loss) [Member] | United Kingdom Plan [Member] |  |  |
Plan net pension (credit)/charge: |  |  |
Recycling of residual reserves | 0.0 | 138.8 | 0.0
Release of historic cumulative translation adjustments | 0.0 | (0.7) | 0.0
Pension scheme settlement | 0.0 | 138.1 | 0.0
Tax relating to the recycling of residual reserves | 0.0 | (34.7) | 0.0
Tax relating to historic cumulative translation adjustments | 0.0 | (11.0) | 0.0
Pension scheme settlement | $ 0.0 | $ 92.4 | $ 0.0

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