Goodwill - Changes in Goodwill (Details) - USD ($) $ in Millions	12 Months Ended
	Jul. 02, 2022	Jul. 03, 2021	Jun. 27, 2020
Changes in goodwill
Balance at the beginning of the period	$ 396.5	$ 381.4
Currency translation and other adjustments	(18.9)	15.1
Acquisitions	10.0
Balance at the end of the period	387.6	396.5
Network Enablement
Changes in goodwill
Balance at the beginning of the period	349.7	334.9
Currency translation and other adjustments	(18.1)	14.8
Acquisitions	0.0
Balance at the end of the period	331.6	349.7
Goodwill balance	633.5	651.6	$ 636.8
Accumulated impairment losses	301.9	301.9	301.9
Service Enablement
Changes in goodwill
Balance at the beginning of the period	4.6	4.3
Currency translation and other adjustments	(0.8)	0.3
Acquisitions	10.0
Balance at the end of the period	13.8	4.6
Goodwill balance	286.3	277.2	276.9
Accumulated impairment losses	272.5	272.6	272.6
Optical Security and Performance Products
Changes in goodwill
Balance at the beginning of the period	42.2	42.2
Balance at the end of the period	42.2	42.2
Goodwill balance	126.7	126.7	126.7
Accumulated impairment losses	$ 84.5	$ 84.5	$ 84.5