Income Taxes - Income Tax Expense (Benefit) (Details) - USD ($) $ in Millions	12 Months Ended
	Jun. 27, 2020	Jun. 29, 2019	Jun. 30, 2018
Federal:
Current	$ 0.0	$ 0.0	$ (4.5)
Deferred	0.0	0.0	(1.7)
Total federal income tax (benefit)	0.0	0.0	(6.2)
State:
Current	2.7	0.1	0.0
Deferred	0.0	0.0	(0.1)
Total state income tax (benefit) expense	2.7	0.1	(0.1)
Foreign:
Current	50.1	33.3	22.0
Deferred	12.5	(1.9)	(2.8)
Total foreign income tax (benefit) expense	62.6	31.4	19.2
Total income tax expense	$ 65.3	$ 31.5	$ 12.9