Accrued Expenses and Other Current Liabilities - Components of Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2018	Jun. 30, 2018
Payables and Accruals [Abstract]
Accounts payable	$ 137.5	$ 191.8
Employee compensation and benefits	149.2	233.2
Accrued broker fees	50.5	85.2
Accrued taxes	18.3	25.3
Accrued dividend payable	56.1	42.5
Customer deposits	42.1	39.2
Other	55.4	53.9
Total	$ 509.1	$ 671.0