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Operating Segments and Geographic Information - Reconciliation to Gross Profit and Operating Income (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Jun. 27, 2020	Mar. 28, 2020	Dec. 28, 2019	Sep. 28, 2019	Jun. 29, 2019	Mar. 30, 2019	Dec. 29, 2018	Sep. 29, 2018	Jun. 27, 2020	Jun. 29, 2019	Jun. 30, 2018
Information on reportable segments
Gross profit	$ 154.6	$ 146.8	$ 189.5	$ 174.4	$ 169.5	$ 153.5	$ 178.0	$ 150.4	$ 665.3	$ 651.4	$ 488.4
Stock-based compensation									(44.6)	(38.2)	(30.5)
Amortization of intangibles									(35.1)	(38.1)	(21.0)
Operating income									118.1	67.4	1.9
Change in Fair Value measurement									31.5	5.9	0.0
Restructuring and related charges									(3.5)	(15.4)	(8.3)
Separation related charges											12.4
Non-segment
Information on reportable segments
Gross profit									(38.9)	(38.7)	(43.7)
Operating income									(92.8)	(130.2)	(119.9)
Acquisition related cost									1.4	5.0	12.7
Corporate reconciling items impacting gross profit
Information on reportable segments
Gross profit									665.3	651.4	488.4
Corporate reconciling items impacting gross profit \| Segment
Information on reportable segments
Gross profit									704.2	690.1	532.1
Corporate reconciling items impacting gross profit \| Non-segment
Information on reportable segments
Stock-based compensation									(4.3)	(3.8)	(3.3)
Amortization of intangibles									(32.7)	(34.4)	(26.7)
Other charges unrelated to core operating performance									(1.9)	(0.5)	(13.7)
Corporate reconciling items impacting operating income
Information on reportable segments
Operating income									118.1	67.4	1.9
Restructuring and related charges									(3.5)	(15.4)	(8.3)
Corporate reconciling items impacting operating income \| Segment
Information on reportable segments
Operating income									210.9	197.6	121.8
Corporate reconciling items impacting operating income \| Non-segment
Information on reportable segments
Stock-based compensation									(44.6)	(38.2)	(30.5)
Amortization of intangibles									(67.8)	(72.5)	(47.7)
Change in Fair Value measurement									(31.5)	(5.9)	0.0
Other charges unrelated to core operating performance									$ 8.4	$ 10.0	$ 33.4