Benefit Plans (Tables)

12 Months Ended

Dec. 31, 2024

Retirement Benefits [Abstract]

Schedule of Reconciliation of Benefit Obligations

The following table provides a reconciliation of the changes in the benefit obligations and in the fair value of the plan assets for the periods described below.

	Pension Benefits								Other Postretirement Benefits
	U.S. Plans				Non-U.S. Plans
	2024		2023		2024		2023		2024		2023
Reconciliation of Benefit Obligations:
Beginning balance	$	294.0	$	319.8	$	263.2	$	247.5	$	18.3	$	21.0
Service cost	0.1		0.1		2.9		2.6		—		—
Interest cost	13.4		15.7		10.7		11.1		0.8		0.9
Participant contributions	—		—		0.2		—		—		—
Plan amendments	—		—		—		0.3		(10.9)		—
Actuarial losses (gains)(1)	(18.1)		6.0		(11.3)		3.3		0.2		(1.0)
Benefit payments	(22.2)		(16.1)		(14.5)		(13.6)		(2.4)		(2.7)
Acquisitions	—		—		10.2		—		—		—
Plan settlements	(2.5)		(31.5)		—		—		—		—
Other	—		—		0.6		—		—		—
Effect of foreign currency exchange rate changes	—		—		(10.6)		12.0		(0.1)		0.1
Benefit obligations ending balance	$	264.7	$	294.0	$	251.4	$	263.2	$	5.9	$	18.3
Reconciliation of Fair Value of Plan Assets:
Beginning balance	$	237.5	$	263.6	$	206.0	$	196.4
Actual return on plan assets	(6.0)		18.7		(7.1)		6.7
Employer contributions	0.1		2.8		6.5		6.6
Participant contributions	—		—		0.2		—
Acquisitions	—		—		8.5		—
Benefit payments	(22.2)		(16.1)		(14.5)		(13.6)
Plan settlements	(2.5)		(31.5)		—		—
Other	—		—		0.6		—
Effect of foreign currency exchange rate changes	—		—		(5.6)		9.9
Fair value of plan assets ending balance	$	206.9	$	237.5	$	194.6	$	206.0
Funded Status as of Period End	$	(57.8)	$	(56.5)	$	(56.8)	$	(57.2)	$	(5.9)	$	(18.3)

(1)Actuarial losses (gains) primarily resulted from changes in discount rates.

Schedule of Component of Accumulated Other Comprehensive (Loss) Income

Amounts recognized as a component of accumulated other comprehensive income (loss) as of December 31, 2024 and 2023 that have not been recognized as a component of net periodic benefit cost are presented in the following table.

	Pension Benefits								Other Postretirement Benefits
	U.S. Plans				Non-U.S. Plans
	2024		2023		2024		2023		2024		2023
Net actuarial losses (gains)	$	(10.8)	$	(11.0)	$	7.6	$	(1.1)	$	(3.2)	$	(4.3)
Prior service cost	—		—		2.7		2.9		(10.9)		0.1
Amounts included in accumulated other comprehensive income (loss)	$	(10.8)	$	(11.0)	$	10.3	$	1.8	$	(14.1)	$	(4.2)

Schedule of Pension and Other Postretirement Benefit Liabilities included in Balance Sheets

Pension and other postretirement benefit liabilities and assets are included in the following captions in the Consolidated Balance Sheets as of December 31, 2024 and 2023.

	2024		2023
Other assets	$	18.5	$	18.8
Accrued liabilities	(6.4)		(6.2)
Pension and other postretirement benefits	(132.6)		(144.6)

Schedule of Pension plans with an Accumulated Benefit Obligation in Excess of Plan Assets

The following table provides information for pension plans with an accumulated benefit obligation in excess of plan assets as of December 31, 2024 and 2023.

	U.S. Pension Plans				Non-U.S. Pension Plans
	2024		2023		2024		2023
Projected benefit obligations	$	264.7	$	294.0	$	119.7	$	105.4
Accumulated benefit obligation	264.7		294.0		112.7		86.4
Fair value of plan assets	206.9		237.5		42.8		17.0

Schedule of Components of Net Periodic Benefit Cost (Income) and Other Amounts Recognized in Other Comprehensive (Loss) Income, Before Income Tax Effects

The following tables provide the components of net periodic benefit cost (income) and other amounts recognized in other comprehensive income (loss), before income tax effects, for the years ended December 31, 2024, 2023 and 2022.

	U.S. Pension Plans
	2024		2023		2022
Net Periodic Benefit Cost:
Service cost	$	0.1	$	0.1	$	4.4
Interest cost	13.4		15.7		11.3
Expected return on plan assets	(12.7)		(13.2)		(13.0)
Amortization of net actuarial loss	—		0.1		—
Net periodic benefit cost	0.8		2.7		2.7
Loss (gain) due to settlement	0.4		(0.4)		(0.5)
Total net periodic benefit cost recognized	$	1.2	$	2.3	$	2.2
Other Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income (Loss):
Net actuarial loss	$	0.6	$	0.5	$	0.4
Amortization of net actuarial gain (loss)	(0.4)		0.3		0.5
Total recognized in other comprehensive income (loss)	$	0.2	$	0.8	$	0.9
Total recognized in net periodic benefit cost and other comprehensive income (loss)	$	1.4	$	3.1	$	3.1

	Non-U.S. Pension Plans
	2024		2023		2022
Net Periodic Benefit Cost (Income):
Service cost	$	2.9	$	2.6	$	3.3
Interest cost	10.7		11.1		5.9
Expected return on plan assets	(11.2)		(11.0)		(11.8)
Amortization of prior service cost	0.2		0.1		0.1
Amortization of net actuarial loss	(1.3)		(1.7)		0.3
Total net periodic benefit cost (income) recognized	$	1.3	$	1.1	$	(2.2)
Other Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income (Loss):
Net actuarial loss (gain)	$	7.0	$	7.5	$	(33.3)
Amortization of net actuarial gain (loss)	1.3		1.7		(0.3)
Prior service cost	—		0.3		—
Amortization of prior service cost	(0.2)		(0.1)		(0.1)
Effect of foreign currency exchange rate changes	0.4		0.3		(3.2)
Total recognized in other comprehensive income (loss)	$	8.5	$	9.7	$	(36.9)
Total recognized in net periodic benefit cost (income) and other comprehensive income (loss)	$	9.8	$	10.8	$	(39.1)

	Other Postretirement Benefits
	2024		2023		2022
Net Periodic Benefit Cost (Income):
Interest cost	$	0.8	$	0.9	$	0.7
Amortization of prior service cost	0.1		0.1		—
Amortization of net actuarial loss	(0.8)		(1.1)		—
Total net periodic benefit cost (income) recognized	$	0.1	$	(0.1)	$	0.7
Other Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income (Loss):
Net actuarial loss (gain)	$	0.2	$	(1.0)	$	(5.0)
Amortization of net actuarial loss	0.8		1.1		—
Prior service cost	(10.9)		—		—
Amortization of prior service cost	(0.1)		(0.1)		—
Total recognized in other comprehensive income (loss)	$	(10.0)	$	—	$	(5.0)
Total recognized in net periodic benefit cost (income) and other comprehensive income (loss)	$	(9.9)	$	(0.1)	$	(4.3)

Schedule of Assumptions Used

The following actuarial assumptions were used to determine net periodic benefit cost (income) and benefit obligations for the years ended December 31, 2024, 2023 and 2022.

	U.S. Pension Plans						Non-U.S. Pension Plans
	2024		2023		2022		2024		2023		2022
Weighted-average actuarial assumptions used to determine net periodic benefit cost:
Discount rate	5.0	%	5.2	%	2.7	%	4.2	%	4.5	%	1.6	%
Expected long-term rate of return on plan assets	5.8	%	5.4	%	3.5	%	5.5	%	5.5	%	4.4	%
Rate of compensation increases	N/A		N/A		3.0	%	5.0	%	4.3	%	4.3	%
Weighted-average actuarial assumptions used to determine benefit obligations:
Discount rate	5.5	%	5.0	%	5.2	%	4.5	%	4.2	%	4.5	%
Rate of compensation increases	N/A		N/A		N/A		5.0	%	5.0	%	4.3	%

The following actuarial assumptions were used to determine other postretirement benefit plans costs and obligations for the years ended December 31, 2024, 2023 and 2022.

	Other Postretirement Benefits
	2024		2023		2022
Discount rate used to determine net periodic benefit cost	4.9% - 5.1%		4.9% - 5.2%		2.4% - 3.0%
Discount rate used to determine benefit obligations	4.4% - 5.4%		4.9% - 5.1%		4.9% - 5.2%
Weighted-average actuarial assumptions used to determine other postretirement benefit plans costs and obligations:
Healthcare cost trend rate assumed for next year	5.1	%	6.8	%	6.8	%
Rate to which the cost trend rate is assumed to decline (the ultimate trend rate)	4.0	%	4.4	%	4.5	%
Year that the date reaches the ultimate trend rate	2040		2035		2034

Schedule of Expected Benefit Payments

The following table reflects the estimated benefit payments for the next five years and for the years 2030 through 2034. The estimated benefit payments for the non-U.S. pension plans were calculated using foreign exchange rates as of December 31, 2024.

	Pension Benefits				Other Postretirement Benefits
	U.S. Plans		Non-U.S. Plans
2025	$	26.4	$	14.7	$	2.4
2026	25.1		14.9		0.4
2027	24.9		14.5		0.4
2028	23.9		15.1		0.3
2029	23.4		17.1		0.3
Aggregate 2030-2034	98.3		86.0		1.3

Schedule of Allocation of Plan Assets

The following table presents the long-term target allocations for these plans as of December 31, 2024.

	U.S. Plans		UK Plan
Asset category:
Equity	16	%	12	%
Fixed income	83	%	56	%
Real estate and other	1	%	32	%
Total	100	%	100	%

Schedule of Changes in Fair Value of Plan Assets

The following tables present the fair values of the Company’s pension plan assets as of December 31, 2024 and 2023 by asset category within the ASC 820 hierarchy (as defined in Note 21 “Fair Value Measurements”).

	December 31, 2024
	Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Investments Measured at NAV (5)		Total
Asset Category
Cash and cash equivalents(1)	$	5.1	$	—	$	—	$	—	$	5.1
Equity funds:
U.S. small-cap	—		—		—		0.9		0.9
U.S. mid-cap	—		—		—		2.6		2.6
U.S. large-cap	—		2.5		—		11.6		14.1
International equity(2)	—		23.2		—		26.5		49.7
Total equity funds	—		25.7		—		41.6		67.3
Fixed income funds:
Corporate bonds - international	—		23.8		—		15.8		39.6
UK index-linked gilts	—		66.0		—		—		66.0
U.S. fixed income - government securities	—		—		—		20.5		20.5
U.S. fixed income - short duration	—		—		—		1.8		1.8
U.S. fixed income - intermediate duration	—		—		—		25.2		25.2
U.S. fixed income - long duration	—		—		—		122.7		122.7
Global fixed income	—		—		—		1.8		1.8
Total fixed income funds	—		89.8		—		187.8		277.6
Other types of investments:
International real estate(3)	—		11.6		—		—		11.6
Other(4)			—		38.1		1.8		39.9
Total	$	5.1	$	127.1	$	38.1	$	231.2	$	401.5

	December 31, 2023
	Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Investments Measured at NAV (5)		Total
Asset Category
Cash and cash equivalents(1)	$	7.1	$	—	$	—	$	—	$	7.1
Equity funds:
U.S. small-cap	—		—		—		3.7		3.7
U.S. large-cap	—		2.0		—		17.5		19.5
International equity(2)	14.2		10.5		—		17.2		41.9
Total equity funds	14.2		12.5		—		38.4		65.1
Fixed income funds:
Corporate bonds - international	—		26.9		—		15.8		42.7
UK index-linked gilts	—		78.7		—		—		78.7
U.S. fixed income - government securities	—		—		—		43.2		43.2
U.S. fixed income - short duration	—		—		—		1.3		1.3
U.S. fixed income - intermediate duration	—		—		—		30.9		30.9
U.S. fixed income - long corporate	—		—		—		122.3		122.3
Global fixed income	—		—		—		7.2		7.2
Total fixed income funds	—		105.6		—		220.7		326.3
Other types of investments:
International real estate(3)	—		15.4		—		—		15.4
Other(4)			—		29.6		—		29.6
Total	$	21.3	$	133.5	$	29.6	$	259.1	$	443.5

(1)Cash and cash equivalents consist of traditional domestic and foreign highly liquid short-term securities with the goal of providing liquidity and preservation of capital while maximizing return on assets.

(2)The International category consists of investment funds focused on companies operating in developed and emerging markets outside of the U.S. These investments target broad diversification across large and mid/small-cap companies and economic sectors.

(3)International real estate consists primarily of equity and debt investments made, directly or indirectly, in various interests in unimproved and improved real properties.

(4)Other investments consist of insurance and reinsurance contracts securing the retirement benefits. The fair value of these contracts was calculated at the discount value of premiums paid by the Company, less expenses charged by the insurance providers. The insurance providers with which the Company has placed these contracts are well-known financial institutions with an established history of providing insurance services.

(5)Certain investments that are measured at fair value using the net asset value per share (or its equivalent) practical expedient have not been categorized in the fair value hierarchy.