Accrued Liabilities (Details) - USD ($) $ in Millions	Jun. 30, 2025	Jun. 30, 2024
Accrued Liabilities, Current [Abstract]
Accrued compensation and benefits	$ 142.6	$ 121.6
Accrued interest expense	18.5	18.5
Accrued postretirement benefits	15.3	15.4
Current portion of lease liabilities	8.0	8.8
Accrued taxes	5.7	4.2
Contract liabilities	5.2	12.3
Accrued pension liabilities	3.3	3.3
Accrued income taxes	3.3	1.0
Derivative financial instruments	2.2	3.6
Other	12.2	13.7
Total accrued liabilities	$ 216.3	$ 202.4