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Pension and Post-Employment Benefits - Defined Benefit Pension Plan (Detail) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Plan net pension (credit)/charge: |  |  |
Pension scheme settlement | $ 92,400,000 |  |
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 | $ 9,600,000 | $ 10,500,000 | $ (1,600,000)
One Time pension scheme settlement charge | $ 155,600,000 | $ 0 | $ 0
United Kingdom Plan [Member] |  |  |
Plan assumptions at December 31, (%): |  |  |
Discount rate | 5.18% | 4.59% | 4.91%
Inflation rate | 2.85% | 2.70% | 2.85%
Rate of return on plan assets - overall on bid-value | 4.20% | 4.25% | 4.00%
Plan asset allocation by category (%): |  |  |
Total plan asset allocation by category | 100.00% | 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% | 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% | 96.00%
United Kingdom [Member] |  |  |
Plan net pension (credit)/charge: |  |  |
Service cost/(credit) | $ 2,400,000 |  |
Interest cost on PBO | 0 |  |
Expected return on plan assets | 0 |  |
Amortization of prior service cost | 0 |  |
Amortization of actuarial net losses | 0 |  |
United Kingdom [Member] | United Kingdom Plan [Member] |  |  |
Plan net pension (credit)/charge: |  |  |
Service cost/(credit) | (4,900,000) | $ 3,400,000 | $ 2,200,000
Interest cost on PBO | 18,600,000 | 19,600,000 | 10,100,000
Expected return on plan assets | (25,900,000) | (25,200,000) | (16,000,000)
Amortization of prior service cost | 16,800,000 | 500,000 | 500,000
Amortization of actuarial net losses | 0 | (1,600,000) | 0
Net periodic cost/(benefit) | 143,400,000 | (3,300,000) | (3,200,000)
Recycling of residual reserves | 138,800,000 | 0 | 0
Pension scheme settlement charge | 155,600,000 | 0 | 0
Release of historic cumulative translation adjustments | (700,000) | 0 | 0
Pension scheme settlement | 138,100,000 | 0 | 0
Tax relating to the recycling of residual reserves | (34,700,000) | 0 | 0
Tax relating to historic cumulative translation adjustments | (11,000,000) | 0 | 0
Pension scheme settlement | 92,400,000 | 0 | 0
Other Nonoperating Income (Expense), Total | (7,300,000) | (6,700,000) | (5,400,000)
One Time pension scheme settlement charge | 116,700,000 | 0 | 0
United Kingdom [Member] | United Kingdom Plan [Member] | Selling General And Administrative Expenses [Member] |  |  |
Plan net pension (credit)/charge: |  |  |
Service cost/(credit) | (4,900,000) | 3,400,000 | 2,200,000
United Kingdom [Member] | United Kingdom Plan [Member] | Other Nonoperating Income (Expense) [Member] |  |  |
Plan net pension (credit)/charge: |  |  |
Amortization of prior service cost | 0 | 500,000 | 500,000
United Kingdom [Member] | United Kingdom Plan [Member] | Pension Scheme Settlement Charge [Member] |  |  |
Plan net pension (credit)/charge: |  |  |
Amortization of prior service cost | 16,800,000 | 0 | 0
Recycling of residual reserves | 138,800,000 | 0 | 0
Tax relating to the amortization of prior service cost | (4,200,000) | 0 | 0
Tax relating to the recycling of residual reserves | (34,700,000) | 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 | 138,800,000 | 0 | 0
Release of historic cumulative translation adjustments | (700,000) | 0 | 0
Pension scheme settlement | 138,100,000 | 0 |
Tax relating to the recycling of residual reserves | (34,700,000) | 0 | 0
Tax relating to historic cumulative translation adjustments | (11,000,000) | 0 | 0
Pension scheme settlement | $ 92,400,000 | $ 0 | $ 0

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