Pension Benefits (Tables) - Pension Plans

12 Months Ended

Dec. 31, 2024

Defined Benefit Plan Disclosure [Line Items]

Schedule of Changes in Fair Value of Plan Assets

Changes in Fair Value of Plan Assets and Changes in Projected Benefit Obligation for the Pension Plan for the years ended December 31, 2024 and 2023 is presented below.

DOLLARS IN MILLIONS	2024		2023
Fair Value of Plan Assets at Beginning of Year	$	16.3	$	315.8
Actual Return on Plan Assets	(1.1)		7.1
Benefits Paid	—		(100.9)
Settlement Benefits	2.6		(205.7)
Assets contributed to 401(k) Plan	(4.7)		—
Assets reverted to the Company	(13.1)		—
Fair Value of Plan Assets at End of Year	—		16.3
Projected Benefit Obligation at Beginning of Year	—		292.2
Interest Cost	—		8.4
Benefits Paid	—		(100.9)
Settlement Benefits	—		(205.7)
Actuarial Gains	—		6.0
Projected Benefit Obligation at End of Year	—		—
Funded Status—Plan Assets in Excess of Projected Benefit Obligation	$	—	$	16.3
Unamortized Amount Reported in AOCI at End of Year	$	—	$	—
Accumulated Benefit Obligation at End of Year	$	—	$	—

Schedule of Allocation of Plan Assets

Asset allocations for the Pension Plan at December 31, 2024 and 2023 by asset category were:

ASSET CATEGORY	2024		2023
Cash and Short-term Investments	—	%	100	%
Total	—	%	100	%

Fair Value, Measurement Inputs, Disclosure

Fair value measurements for the Pension Plan’s assets at December 31, 2023 are summarized below.

DOLLARS IN MILLIONS	Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Measured at Net Asset Value		Fair Value
Equity Securities:
Other Equity Interests:
Limited Liability Companies and Limited Partnerships	—		—		—		0.1		0.1
Short-term Investments	16.2		—		—		—		16.2
Total	$	16.2	$	—	$	—	$	0.1	$	16.3

Schedule of Defined Benefit Plan Amounts Recognized in Other Comprehensive Income (Loss)

The components of Comprehensive Pension (Income) Expense for the Pension Plan for the years ended December 31, 2024, 2023 and 2022 were:

DOLLARS IN MILLIONS	2024		2023		2022
Service Cost Earned During the Year	$	—	$	—	$	—
Interest Cost on Projected Benefit Obligation	—		8.4		8.7
Expected Return on Plan Assets	—		(7.9)		(7.4)
Amortization of Prior Service Cost	—		0.4		0.7
Amortization of Actuarial Loss	—		—		1.8
Settlement (Income) Expense	(2.6)		70.2		—
Pension (Income) Expense Recognized in Consolidated Statements of Income (Loss)	(2.6)		71.1		3.8
Unrecognized Pension Loss Arising During the Year	—		—		(12.0)
Prior Service Cost Arising During the Year	—		—		—
Amortization of Prior Service Cost	—		—		(0.7)
Amortization of Accumulated Unrecognized Pension Loss	—		—		(1.8)
Comprehensive Pension (Income) Expense	$	(2.6)	$	71.1	$	(10.7)

Schedule of Assumptions Used

The weighted-average discount rate, service cost discount rate, interest cost discount rate, rate of increase in future compensation levels and expected long-term rate of return on plan assets used to develop the components of Pension Expense for the Pension Plan for the years ended December 31, 2024, 2023 and 2022 were:

	2024		2023		2022
Weighted-average Discount Rate	—	%	5.05	%	2.89	%
Interest Cost Discount Rate	—		4.92		2.35
Rate of Increase in Future Compensation Levels	N/A		N/A		3.40
Expected Long Term Rate of Return on Plan Assets	—		3.79		2.08