Other Expense, Net - Schedule of Other Expense, Net (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Mar. 31, 2025	Mar. 31, 2024	Mar. 31, 2025	Mar. 31, 2024
Other Income and Expenses [Abstract]
Interest income	$ (1.6)	$ (0.1)	$ (5.5)	$ (0.4)
Foreign exchange losses (gains)	0.2	(0.1)	0.0	1.3
Unrealized losses (gains) on company-owned life insurance contracts and investments held in rabbi trusts	1.3	(2.5)	(0.6)	(5.0)
Pension earnings, interest and deferrals	3.9	3.7	11.6	10.6
Pension settlement charge	0.0	(51.9)	0.0	(51.9)
Other	0.0	0.0	0.1	0.1
Total other expense, net	$ 3.8	$ 52.9	$ 5.6	$ 58.5