Goodwill (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Jul. 02, 2016	Apr. 01, 2017
Changes in goodwill
Balance at the beginning of the period		$ 152.1
Currency translation adjustments		(1.4)
Balance at the end of the period	$ 152.1	150.7
Network Enablement
Changes in goodwill
Balance at the beginning of the period		143.8
Currency translation adjustments		(1.4)
Balance at the end of the period	143.8	142.4
Goodwill impairment	0.0
Optical Security and Performance Products
Changes in goodwill
Balance at the beginning of the period		8.3
Currency translation adjustments		0.0
Balance at the end of the period	8.3	$ 8.3
Goodwill impairment	0.0
Service Enablement
Changes in goodwill
Goodwill impairment	$ 91.4