Operating Segments and Geographic Information - Information on Reportable Segments (Details) $ in Millions	3 Months Ended
Sep. 28, 2019 USD ($) segment	Sep. 29, 2018 USD ($)
Information on reportable segments
Number of broad business categories (in segment) \| segment	2
Total net revenue	$ 299.8	$ 268.5
Gross profit	$ 174.4	$ 150.4
Gross margin (as a percent)	58.20%	56.00%
Operating income	$ 20.7	$ (1.2)
Operating margin (as a percent)	6.90%	(0.40%)
Other Items
Information on reportable segments
Total net revenue	$ 0.0	$ 0.0
Gross profit	(9.5)	(10.2)
Operating income	(32.0)	(45.0)
Network and Service Enablement \| Segment Measures
Information on reportable segments
Total net revenue	219.8	190.7
Gross profit	$ 140.6	$ 121.2
Gross margin (as a percent)	64.00%	63.60%
Operating income	$ 22.3	$ 16.4
Operating margin (as a percent)	10.10%	8.60%
Network and Service Enablement \| Network Enablement \| Segment Measures
Information on reportable segments
Total net revenue	$ 198.9	$ 164.5
Gross profit	$ 128.0	$ 102.9
Gross margin (as a percent)	64.40%	62.60%
Network and Service Enablement \| Service Enablement \| Segment Measures
Information on reportable segments
Total net revenue	$ 20.9	$ 26.2
Gross profit	$ 12.6	$ 18.3
Gross margin (as a percent)	60.30%	69.80%
Optical Security and Performance Products \| Segment Measures
Information on reportable segments
Total net revenue	$ 80.0	$ 77.8
Gross profit	$ 43.3	$ 39.4
Gross margin (as a percent)	54.10%	50.60%
Operating income	$ 30.4	$ 27.4
Operating margin (as a percent)	38.00%	35.20%
Product revenue
Information on reportable segments
Total net revenue	$ 264.8	$ 241.1
Product revenue \| Other Items
Information on reportable segments
Total net revenue	0.0	0.0
Product revenue \| Network and Service Enablement \| Segment Measures
Information on reportable segments
Total net revenue	184.9	163.5
Product revenue \| Network and Service Enablement \| Network Enablement \| Segment Measures
Information on reportable segments
Total net revenue	177.2	149.9
Product revenue \| Network and Service Enablement \| Service Enablement \| Segment Measures
Information on reportable segments
Total net revenue	7.7	13.6
Product revenue \| Optical Security and Performance Products \| Segment Measures
Information on reportable segments
Total net revenue	79.8	77.6
Service revenue
Information on reportable segments
Total net revenue	35.0	27.4
Service revenue \| Other Items
Information on reportable segments
Total net revenue	0.0	0.0
Service revenue \| Network and Service Enablement \| Segment Measures
Information on reportable segments
Total net revenue	34.9	27.2
Service revenue \| Network and Service Enablement \| Network Enablement \| Segment Measures
Information on reportable segments
Total net revenue	21.7	14.6
Service revenue \| Network and Service Enablement \| Service Enablement \| Segment Measures
Information on reportable segments
Total net revenue	13.2	12.6
Service revenue \| Optical Security and Performance Products \| Segment Measures
Information on reportable segments
Total net revenue	$ 0.2	$ 0.2

Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

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