Leases - ROU Assets and Liabilities (Details) - USD ($) $ in Millions	Jun. 30, 2023	Jun. 30, 2022
Operating lease assets:
Other assets	$ 43.9	$ 42.9
Operating lease liabilities:
Accrued liabilities	9.1	9.9
Other liabilities	43.6	42.7
Total operating lease liabilities	$ 52.7	$ 52.6
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Other assets	Other assets
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	Accrued liabilities	Accrued liabilities
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	Other liabilities	Other liabilities
Operating Lease, Liability, Statement of Financial Position [Extensible Enumeration]	Liabilities	Liabilities