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Restructuring Activities - Restructuring Liability Activities (Detail) - USD ($) $ in Millions	12 Months Ended
	Jun. 27, 2020	Jun. 29, 2019	Jun. 30, 2018
Fiscal 2020 Restructuring Plan [Member] \| Employee Severance and Benefits [Member]
Restructuring Cost And Reserve [Line Items]
Additional accruals	$ 25.1
Cash payments	(19.0)
Ending Balance	6.1
Fiscal 2019 Retructucturing Plan [Member] \| Employee Severance and Benefits [Member]
Restructuring Cost And Reserve [Line Items]
Beginning Balance	5.2
Additional accruals	7.9	$ 17.7
Cash payments	$ (13.1)	(12.5)
Ending Balance		5.2
November 2017 and April 2018 Restructuring Plan [Member]
Restructuring Cost And Reserve [Line Items]
Beginning Balance		2.3
Additional accruals		0.2	$ 12.0
Cash payments		(2.5)	(9.0)
Ending Balance			2.3
Non-cash settlements			(0.7)
November 2017 and April 2018 Restructuring Plan [Member] \| Employee Severance and Benefits [Member]
Restructuring Cost And Reserve [Line Items]
Beginning Balance		2.2
Additional accruals		0.2	11.0
Cash payments		(2.4)	(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]
Beginning Balance		0.1
Additional accruals			1.0
Cash payments		$ (0.1)	(0.2)
Ending Balance			0.1
Non-cash settlements			$ (0.7)