Employee Benefit Plans - Components of Net Pension (Income)/Expense (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2024	Dec. 31, 2023
Retirement Benefits [Abstract]
Service cost – benefits earned during the period	$ 1.5	$ 1.3	$ 3.0	$ 2.6
Interest cost on projected benefits	21.9	21.1	43.7	42.3
Expected return on plan assets	(29.0)	(29.0)	(58.0)	(58.0)
Net amortization and deferral	0.7	0.8	1.5	1.5
Net pension income	$ (4.9)	$ (5.8)	$ (9.8)	$ (11.6)