Pension and Other Postretirement Benefits (Tables)

9 Months Ended

Mar. 31, 2025

Retirement Benefits [Abstract]

Schedule of Components of the Net Periodic Pension (Income) Expense

The components of the net periodic pension expense (income) related to the Company's pension and other postretirement benefits for the three and nine months ended March 31, 2025 and 2024 were as follows:

	Three Months Ended March 31,
	2025		2024		2025		2024
($ in millions)	Pension Plans				Other Postretirement Plans
Service cost	$	1.9	$	2.1	$	0.4	$	0.3
Interest cost	9.7		10.4		2.5		2.6
Expected return on plan assets	(7.5)		(8.3)		(2.1)		(1.8)
Amortization of net loss (gain)	1.9		1.9		(1.4)		(0.6)
Amortization of prior service cost (credits)	0.5		0.5		0.3		(1.0)
Pension settlement charge	—		51.9		—		—
Net pension expense (income)	$	6.5	$	58.5	$	(0.3)	$	(0.5)

	Nine Months Ended March 31,
	2025		2024		2025		2024
($ in millions)	Pension Plans				Other Postretirement Plans
Service cost	$	6.0	$	6.2	$	1.0	$	1.1
Interest cost	29.0		34.0		7.5		7.6
Expected return on plan assets	(22.5)		(28.5)		(6.3)		(5.5)
Amortization of net loss (gain)	5.7		6.2		(4.2)		(1.9)
Amortization of prior service cost (credits)	1.5		1.6		0.9		(2.9)
Pension settlement charge	—		51.9		—		—
Net pension expense (income)	$	19.7	$	71.4	$	(1.1)	$	(1.6)