Payables and Accrued Expenses - Components of Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2022	Jun. 30, 2022
Payables and Accruals [Abstract]
Accounts payable	$ 169.8	$ 244.9
Employee compensation and benefits	231.2	348.1
Accrued dividend payable	85.3	75.0
Accrued broker fees	71.8	154.1
Business process outsourcing administration fees	63.3	65.5
Customer deposits	53.8	58.7
Operating lease liabilities	39.2	45.4
Accrued taxes	46.2	40.9
Other	63.6	82.2
Total	$ 824.2	$ 1,114.9
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Total	Total