Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

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Amount of increase (decrease) in the accrual for restructuring costs.

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Restructuring Activities - Restructuring Liability Activities (Detail) - USD ($) $ in Millions	12 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2016
November 2017 and April 2018 Restructuring Plan [Member]
Restructuring Cost And Reserve [Line Items]
Additional accruals	$ 12.0
Cash payments	(9.0)
Non-cash settlements	(0.7)
Ending Balance	2.3
November 2017 and April 2018 Restructuring Plan [Member] \| Employee Severance and Benefits [Member]
Restructuring Cost And Reserve [Line Items]
Additional accruals	11.0
Cash payments	(8.8)
Ending Balance	2.2
November 2017 and April 2018 Restructuring Plan [Member] \| Facility Consolidation and Related Charges [Member]
Restructuring Cost And Reserve [Line Items]
Additional accruals	1.0
Cash payments	(0.2)
Non-cash settlements	(0.7)
Ending Balance	0.1
June 2016 Restructuring Plan [Member]
Restructuring Cost And Reserve [Line Items]
Beginning Balance		$ 6.7
Additional accruals		7.3	$ 6.7
Adjustments	(0.2)
Cash payments	(0.4)	(12.6)
Non-cash settlements		(0.8)
Ending Balance		0.6	6.7
June 2016 Restructuring Plan [Member] \| Employee Severance and Benefits [Member]
Restructuring Cost And Reserve [Line Items]
Beginning Balance		6.7
Additional accruals		5.0	6.7
Cash payments		(11.7)
Ending Balance			$ 6.7
June 2016 Restructuring Plan [Member] \| Facility Consolidation and Related Charges [Member]
Restructuring Cost And Reserve [Line Items]
Additional accruals		2.3
Adjustments	(0.2)
Cash payments	$ (0.4)	(0.9)
Non-cash settlements		(0.8)
Ending Balance		$ 0.6