Financial Instruments and Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2024

Fair Value Disclosures [Abstract]

Schedule of Fair Values of Interest rate Swaps and Interest Rate Caps are Recorded in Consolidated Balance Sheets

As of December 31, 2024, the fair values of the interest rate swaps and interest rate caps are recorded in the Consolidated Balance Sheets as follows:

				Quoted Prices in		Significant		Significant
		December 31,		Active Markets		Observable Inputs		Unobservable Inputs
(dollars in millions)	Balance Sheet Location	2024		Level 1		Level 2		Level 3
Assets:
Interest Rate Swap	Other current assets	$	6.5	$	—	$	6.5	$	—
Interest Rate Swap	Other noncurrent assets	$	2.8	$	—	$	2.8	$	—
Interest Rate Cap	Other current assets	$	1.1	$	—	$	1.1	$	—
Interest Rate Cap	Other noncurrent assets	$	0.2	$	—	$	0.2	$	—
Liabilities:
Interest Rate Swap	Other current liabilities	$	0.1	$	—	$	0.1	$	—

As of December 31, 2023, the fair values of the interest rate swaps and interest rate caps are recorded in the Consolidated Balance Sheets as follows:

				Quoted Prices in		Significant		Significant
		December 31,		Active Markets		Observable Inputs		Unobservable Inputs
(dollars in millions)	Balance Sheet Location	2023		Level 1		Level 2		Level 3
Assets:
Interest Rate Swap	Other current assets	$	10.7	$	—	$	10.7	$	—
Interest Rate Swap	Other noncurrent assets	$	1.8	$	—	$	1.8	$	—
Interest Rate Cap	Other current assets	$	3.2	$	—	$	3.2	$	—
Liabilities:
Interest Rate Swap	Other noncurrent liabilities	$	3.8	$	—	$	3.8	$	—
Interest Rate Cap	Other noncurrent liabilities	$	2.6	$	—	$	2.6	$	—

Schedule of Summarizes the Location of Gains in the Consolidated Statements of Operations in Addition to the Derivative Contract Type

The following table summarizes the location of gains in the Consolidated Statements of Operations that were recognized during the years ended December 31, 2024 and 2023, in addition to the derivative contract type:

		Year ended December 31,
(dollars in millions)	Statement of Operations Location	2024			2023
Interest Rate Swap	Other income, net	$	(17.0	)	$	(9.3	)
Interest Rate Cap	Other income, net	$	(6.1	)	$	(3.8	)

Schedule of Carrying and Fair Values by Balance Sheet Grouping

The carrying and fair values of these items are as follows:

	December 31, 2024				December 31, 2023
(dollars in millions)	Carrying Value		Fair Value		Carrying Value		Fair Value
Long-term debt, including current portion*	$	1,751.2	$	1,755.5	$	1,842.3	$	1,815.1
Other financing arrangements		40.8		39.2		43.6		37.7

* Excludes finance leases, other financing arrangements and note issuance costs