Retirement and Postretirement Plans - Amounts Recognized in the Balance Sheet (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Non-current assets	$ 5.5	$ 9.9
Current liabilities	(66.5)	(43.5)
Non-current liabilities	(110.2)	(160.5)
Pension
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Non-current assets	5.5	9.9
Current liabilities	(65.3)	(42.3)
Non-current liabilities	(80.7)	(130.6)
Total assets (liabilities) recognized	(140.5)	(163.0)
Pension \| United States of America \| Bargaining Plan
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Current liabilities	(64.7)	(41.7)
Non-current liabilities	(65.2)	(114.5)
Total assets (liabilities) recognized	(129.9)	(156.2)
Pension \| United States of America \| Salaried Plan
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Non-current assets	0.0	5.6
Total assets (liabilities) recognized	0.0	5.6
Pension \| United States of America \| Supplemental Plan
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Current liabilities	(0.6)	(0.6)
Non-current liabilities	(15.5)	(15.9)
Total assets (liabilities) recognized	(16.1)	(16.5)
Pension \| United Kingdom \| Pension Scheme
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Non-current assets	5.3	4.3
Total assets (liabilities) recognized	5.3	4.3
Pension \| Mexico \| Pension Plan
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Non-current assets	0.2
Non-current liabilities	0.0	(0.2)
Total assets (liabilities) recognized	0.2	(0.2)
Postretirement
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Current liabilities	(1.2)	(1.2)
Non-current liabilities	(29.5)	(29.9)
Total assets (liabilities) recognized	$ (30.7)	$ (31.1)

Amount of asset (liability), recognized in statement of financial position, for defined benefit pension and other postretirement plans.

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