Income Taxes (Tables)

12 Months Ended

Dec. 31, 2023

Income Tax Disclosure [Abstract]

Schedule of Consolidated Income (loss) from Continuing Operations Before Income Taxes by Location

The “Income before income tax expense” line item in the consolidated statements of operations consisted of:

(Dollars in millions)	2023		2022		2021
Domestic	$	9.1	$	58.4	$	34.4
Foreign	67.2		82.0		91.9
Total	$	76.3	$	140.4	$	126.3

Schedule of Income Tax Expense (Benefit) by Location

The “Income tax expense” line item in the consolidated statements of operations consisted of:

(Dollars in millions)	Current		Deferred		Total
2023
Domestic	$	0.4	$	(0.6)	$	(0.2)
Foreign	22.9		(3.0)		19.9
Total	$	23.3	$	(3.6)	$	19.7
2022
Domestic	$	26.8	$	(18.8)	$	8.0
Foreign	17.6		(1.8)		15.8
Total	$	44.4	$	(20.6)	$	23.8
2021
Domestic	$	5.2	$	(2.9)	$	2.3
Foreign	16.2		(0.3)		15.9
Total	$	21.4	$	(3.2)	$	18.2

Schedule of Deferred Tax Assets and Liabilities

Deferred tax assets and liabilities as of December 31, 2023 and 2022, were comprised of the following:

(Dollars in millions)	2023		2022
Deferred tax assets
Accrued employee benefits and compensation	$	7.7	$	8.7
Net operating loss carryforwards	11.8		4.4
Tax credit carryforwards	6.7		2.8
Reserves and accruals	5.7		4.7
Operating leases	3.6		4.2
Capitalized research and development	25.6		21.3
Other	6.9		10.2
Total deferred tax assets	68.0		56.3
Less deferred tax asset valuation allowance	(11.4)		(2.8)
Total deferred tax assets, net of valuation allowance	56.6		53.5
Deferred tax liabilities
Depreciation and amortization	17.7		14.4
Postretirement benefit obligations	0.7		0.7
Unremitted earnings	1.5		2.6
Operating leases	4.1		4.6
Other	5.8		4.2
Total deferred tax liabilities	29.8		26.5
Net deferred tax asset (liability)	$	26.8	$	27.0

Schedule of Effective Income Tax Rate Reconciliation

Income tax expense differs from the amount computed by applying the U.S. federal statutory income tax rate to income before income taxes. The reasons for this difference were as follows:

(Dollars in millions)	2023		2022		2021
Tax expense at Federal statutory income tax rate	$	16.0	$	29.5	$	26.5
Impact of foreign operations	4.0		1.5		2.0
Foreign source income, net of tax credits	(2.3)		(6.5)		(4.9)
State tax, net of federal	(0.5)		6.9		0.2
Deferred tax adjustment	1.2		—		—
Unrecognized tax benefits	(0.2)		1.9		(8.8)
Equity compensation excess tax deductions	0.3		(3.0)		0.3
General business credits	(2.4)		(0.8)		(0.9)
Distribution related foreign taxes	1.1		1.5		2.5
Executive compensation limitation	0.9		2.9		1.6
Valuation allowance change	0.7		(6.9)		0.5
Other	0.9		(3.2)		(0.8)
Income tax expense	$	19.7	$	23.8	$	18.2

Schedule of Reconciliation of Unrecognized Tax Benefits

Unrecognized tax benefits, excluding potential interest and penalties, for the years ended December 31, 2023 and 2022, were as follows:

(Dollars in millions)	2023		2022		2021
Beginning balance as of January 1	$	8.9	$	6.6	$	15.7
Gross increases - current period tax positions	1.1		3.4		1.0
Gross increases - tax positions in prior periods	—		0.2		1.2
Gross decreases - tax positions in prior periods	(0.5)		(0.2)		(9.2)
Foreign currency exchange	0.1		(0.1)		—
Settlements	0.1		(1.0)		(2.1)
Lapse of statue of limitations	$	(1.2)	$	—	$	—
Ending balance as of December 31	$	8.5	$	8.9	$	6.6