Accrued Expenses and Other Current Liabilities - Components of Accrued Expenses and Other Current Liabilities (Detail) (USD $) In Millions, unless otherwise specified	Sep. 30, 2013	Jun. 30, 2013
Payables And Accruals [Abstract]
Employee compensation and benefits	$ 82.9	$ 143.1
Accrued broker fees	24.3	49.2
Accrued income tax liability	27.7	51.8
Accrued dividend payable	24.1	21.0
Other	12.8	12.1
Total	$ 171.8	$ 277.2