Pension Benefits and Other Postretirement Benefits (Tables)

3 Months Ended

Mar. 31, 2024

Retirement Benefits [Abstract]

Schedule of Components of Net Periodic Benefit Cost

The components of net periodic benefit (credit) cost were as follows:

	Pension Benefits
	Three Months Ended
	March 31,
(Dollars in millions)	2024		2023
Interest cost	0.2		0.3
Expected return of plan assets	(0.3)		(0.4)
Amortization of net loss (gain)	0.1		0.1
Net periodic benefit cost (credit)	$	—	$	—