Income Taxes-Components of Income Tax Expense (Details) - USD ($) $ in Millions	12 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2018
Current Income Tax Expense (Benefit), Continuing Operations [Abstract]
Federal	$ 1.2	$ 2.4	$ 14.1
State and local	0.8	0.3	0.1
Non-U.S.	33.0	25.8	24.9
Total current	35.0	28.5	39.1
Deferred:
Federal	11.1	3.6	24.2
State and local	6.9	(11.6)	(1.0)
Non-U.S.	(13.3)	2.4	6.1
Total deferred	4.7	(5.6)	29.3
Total provision	$ 39.7	$ 22.9	$ 68.4