Retirement Benefit Plans - Components of Net Pension Expense (Detail) - USD ($)
$ in Millions |
12 Months Ended |
Dec. 31, 2025 |
Dec. 31, 2024 |
Dec. 31, 2023 |
| United States [Member] |
|
|
|
| Net Periodic Benefit Cost |
|
|
|
| Service cost |
$ 0.2
|
$ 0.3
|
$ 0.4
|
| Interest cost |
$ 18.1
|
$ 18.3
|
$ 18.7
|
| Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Interest Cost, Statement of Income or Comprehensive Income [Extensible Enumeration] |
Other Nonoperating Income (Expense)
|
Other Nonoperating Income (Expense)
|
Other Nonoperating Income (Expense)
|
| Expected return on plan assets |
$ (30.7)
|
$ (30.7)
|
$ (30.1)
|
| Defined Benefit Plan, Net Periodic Benefit (Cost) Credit, Expected Return (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] |
Other Nonoperating Income (Expense)
|
Other Nonoperating Income (Expense)
|
Other Nonoperating Income (Expense)
|
| Settlements |
$ 0.0
|
$ 0.0
|
$ 0.1
|
| Defined Benefit Plan, Net Periodic Benefit (Cost) Credit, Settlement Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] |
Other Nonoperating Income (Expense)
|
Other Nonoperating Income (Expense)
|
Other Nonoperating Income (Expense)
|
| Amortization of prior service cost |
$ 0.2
|
$ 0.1
|
$ 0.2
|
| Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Amortization of Prior Service Cost (Credit), Statement of Income or Comprehensive Income [Extensible Enumeration] |
Other Nonoperating Income (Expense)
|
Other Nonoperating Income (Expense)
|
Other Nonoperating Income (Expense)
|
| Amortization of unrecognized actuarial loss |
$ 2.8
|
$ 3.5
|
$ 2.8
|
| Defined Benefit Plan, Net Periodic Benefit (Cost) Credit, Amortization of Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] |
Other Nonoperating Income (Expense)
|
Other Nonoperating Income (Expense)
|
Other Nonoperating Income (Expense)
|
| Net periodic (income) benefit expense |
$ (9.4)
|
$ (8.5)
|
$ (7.9)
|
| Foreign [Member] |
|
|
|
| Net Periodic Benefit Cost |
|
|
|
| Service cost |
20.9
|
18.1
|
15.5
|
| Interest cost |
$ 12.4
|
$ 14.2
|
$ 15.7
|
| Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Interest Cost, Statement of Income or Comprehensive Income [Extensible Enumeration] |
Other Nonoperating Income (Expense)
|
Other Nonoperating Income (Expense)
|
Other Nonoperating Income (Expense)
|
| Expected return on plan assets |
$ (24.2)
|
$ (24.4)
|
$ (22.5)
|
| Defined Benefit Plan, Net Periodic Benefit (Cost) Credit, Expected Return (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] |
Other Nonoperating Income (Expense)
|
Other Nonoperating Income (Expense)
|
Other Nonoperating Income (Expense)
|
| Settlements |
$ (2.4)
|
$ (2.2)
|
$ (2.6)
|
| Defined Benefit Plan, Net Periodic Benefit (Cost) Credit, Settlement Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] |
Other Nonoperating Income (Expense)
|
Other Nonoperating Income (Expense)
|
Other Nonoperating Income (Expense)
|
| Amortization of prior service cost |
$ 0.9
|
$ (3.1)
|
$ (4.4)
|
| Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Amortization of Prior Service Cost (Credit), Statement of Income or Comprehensive Income [Extensible Enumeration] |
Other Nonoperating Income (Expense)
|
Other Nonoperating Income (Expense)
|
Other Nonoperating Income (Expense)
|
| Amortization of unrecognized actuarial loss |
$ 0.4
|
$ 0.6
|
$ (2.2)
|
| Defined Benefit Plan, Net Periodic Benefit (Cost) Credit, Amortization of Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] |
Other Nonoperating Income (Expense)
|
Other Nonoperating Income (Expense)
|
Other Nonoperating Income (Expense)
|
| Net periodic (income) benefit expense |
$ 8.0
|
$ 3.2
|
$ (0.5)
|