Leases - Summary of Right-of-Use Assets and Lease Liabilities (Details) - USD ($) $ in Millions	Mar. 31, 2023	Jun. 30, 2022
Operating lease assets:
Other assets	$ 37.5	$ 42.9
Operating lease liabilities:
Accrued liabilities	9.0	9.9
Other liabilities	37.5	42.7
Total operating lease liabilities	$ 46.5	$ 52.6