Goodwill (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
	Jan. 02, 2016	Jun. 27, 2015
Changes in goodwill
Balance at the beginning of the period	$ 255.5
Currency translation and other adjustments	(3.4)
Goodwill allocation - WaveReady	(6.0)
Balance at the end of the period	246.1	$ 255.5
Goodwill impairment		0.0
Network Enablement
Changes in goodwill
Balance at the beginning of the period	154.5
Currency translation and other adjustments	(2.2)
Goodwill allocation - WaveReady	(6.0)
Balance at the end of the period	146.3	154.5
Service Enablement
Changes in goodwill
Balance at the beginning of the period	92.7
Currency translation and other adjustments	(1.2)
Goodwill allocation - WaveReady	0.0
Balance at the end of the period	91.5	92.7
Optical Security and Performance Products
Changes in goodwill
Balance at the beginning of the period	8.3
Currency translation and other adjustments	0.0
Goodwill allocation - WaveReady	0.0
Balance at the end of the period	$ 8.3	$ 8.3