Pension and Other Postretirement Benefits (Tables)

9 Months Ended

Mar. 31, 2024

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, 2024 and 2023 were as follows:

	Three Months Ended March 31,
	2024		2023		2024		2023
($ in millions)	Pension Plans				Other Postretirement Plans
Service cost	$	2.1	$	2.0	$	0.3	$	0.5
Interest cost	10.4		11.5		2.6		2.4
Expected return on plan assets	(8.3)		(11.2)		(1.8)		(1.7)
Amortization of net loss (gain)	1.9		2.4		(0.6)		(0.4)
Amortization of prior service cost (credits)	0.5		0.5		(1.0)		(1.0)
Pension settlement charge	51.9		—		—		—
Net pension expense (income)	$	58.5	$	5.2	$	(0.5)	$	(0.2)

	Nine Months Ended March 31,
	2024		2023		2024		2023
($ in millions)	Pension Plans				Other Postretirement Plans
Service cost	$	6.2	$	5.9	$	1.1	$	1.5
Interest cost	34.0		34.5		7.6		7.2
Expected return on plan assets	(28.5)		(33.6)		(5.5)		(5.1)
Amortization of net loss (gain)	6.2		7.2		(1.9)		(1.2)
Amortization of prior service cost (credits)	1.6		1.5		(2.9)		(3.0)
Pension settlement charge	51.9		—		—		—
Net pension expense (income)	$	71.4	$	15.5	$	(1.6)	$	(0.6)