Payables and Accrued Expenses - Components of Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2021	Jun. 30, 2021
Payables and Accruals [Abstract]
Accounts payable	$ 192.2	$ 248.9
Employee compensation and benefits	236.8	343.7
Accrued broker fees	80.5	136.0
Accrued dividend payable	74.7	66.8
Business process outsourcing administration fees	74.1	66.1
Customer deposits	64.1	55.5
Operating lease liabilities	40.5	40.2
Accrued taxes	35.8	42.6
Other	79.9	102.9
Total	$ 878.6	$ 1,102.7
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Payables and accrued expenses	Payables and accrued expenses