Payables and Accrued Expenses - Components of Payables and Accrued Expenses (Details) - USD ($) $ in Millions	Jun. 30, 2023	Jun. 30, 2022
Other Liabilities Disclosure [Abstract]
Accounts payable	$ 157.3	$ 244.9
Employee compensation and benefits	335.6	348.1
Accrued broker fees	148.0	154.1
Accrued dividend payable	85.6	75.0
Accrued taxes	69.7	40.9
Customer deposits	65.6	58.7
Business process outsourcing administration fees	61.7	65.5
Operating lease liabilities	40.9	45.4
Other	55.1	82.2
Total	$ 1,019.5	$ 1,114.9
Operating lease liabilities - Current, extensible list	Payables and accrued expenses	Payables and accrued expenses