Retirement and Postretirement Plans - Change in Plan Assets (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023
Pension
Change in plan assets:
Fair value of plan assets at the beginning of year	$ 525.6	$ 549.4
Actual return on plan assets	(1.5)	31.1
Company contributions / payments	39.8	1.8
Benefits paid	(48.2)	(53.8)
Settlements	(118.2)	(6.0)
Foreign currency translation adjustment	(0.9)	3.1
Fair value of plan assets at end of year	396.6	525.6
Funded status at end of year	(140.5)	(163.0)
Pension \| United States of America \| Bargaining Plan
Change in plan assets:
Fair value of plan assets at the beginning of year	334.7	353.9
Actual return on plan assets	2.8	19.3
Company contributions / payments	40.9
Benefits paid	(36.7)	(38.5)
Settlements	0.0	0.0
Fair value of plan assets at end of year	341.7	334.7
Funded status at end of year	(129.9)	(156.2)
Pension \| United States of America \| Salaried Plan
Change in plan assets:
Fair value of plan assets at the beginning of year	129.6	137.7
Actual return on plan assets	(0.9)	9.3
Company contributions / payments	(3.6)
Benefits paid	(6.9)	(11.4)
Settlements	(118.2)	(6.0)
Fair value of plan assets at end of year	0.0	129.6
Funded status at end of year	0.0	5.6
Pension \| United States of America \| Supplemental Plan
Change in plan assets:
Company contributions / payments	0.6	0.6
Benefits paid	(0.6)	(0.6)
Settlements	0.0	0.0
Funded status at end of year	(16.1)	(16.5)
Pension \| United Kingdom \| Pension Scheme
Change in plan assets:
Fair value of plan assets at the beginning of year	61.0	57.5
Actual return on plan assets	(3.4)	2.5
Company contributions / payments	1.9	1.2
Benefits paid	(4.0)	(3.3)
Foreign currency translation adjustment	(0.9)	3.1
Fair value of plan assets at end of year	54.6	61.0
Funded status at end of year	5.3	4.3
Pension \| Mexico \| Pension Plan
Change in plan assets:
Fair value of plan assets at the beginning of year	0.3	0.3
Fair value of plan assets at end of year	0.3	0.3
Funded status at end of year	0.2	(0.2)
Postretirement
Change in plan assets:
Fair value of plan assets at the beginning of year	53.8	59.2
Actual return on plan assets	2.7	5.3
Company contributions / payments	2.4	1.0
Benefits paid	(9.5)	(11.7)
Fair value of plan assets at end of year	49.4	53.8
Funded status at end of year	$ (30.7)	$ (31.1)

Defined benefit pension plan surplus.

No definition available.

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- Definition

Amount of increase (decrease) in plan assets of defined benefit plan from actual return (loss) determined by change in fair value of plan assets adjusted for contributions, benefit payments, and other expenses.

+ References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

+ References

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- Definition

Amount of funded (unfunded) status of defined benefit plan, measured as difference between fair value of plan assets and benefit obligation. Includes, but is not limited to, overfunded (underfunded) status.

+ References

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- Definition

Amount of payment to participant under defined benefit plan which decreases plan assets. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services.

+ References

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- Definition

Amount of foreign currency translation gain (loss) which increases (decreases) plan assets of defined benefit plan.

+ References

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- Definition

Amount of payment, which decreases plan assets of defined benefit plan, for irrevocable action relieving primary responsibility for benefit obligation and eliminating risk for obligation and assets used to effect settlement. Transaction constituting settlement includes, but is not limited to, making lump-sum cash payment to participant in exchange for their rights to receive specified benefits and purchasing nonparticipating annuity contract.

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