Supplemental Balance Sheet Information - Other Accrued Liabilities (Detail) - USD ($) $ in Millions	Sep. 30, 2017	Jun. 30, 2017
Balance Sheet Related Disclosures [Abstract]
Accrued employee-related expenses	$ 82.8	$ 96.4
Restructuring accrual	4.7	5.9
Accrued interest	6.4	0.9
Deferred revenue and fees	77.0	84.9
Accrued income tax	17.8	24.7
Other accrued liabilities and expenses	77.7	68.4
Other accrued liabilities	$ 266.4	$ 281.2