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Basis of Presentation - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Jun. 29, 2019	Jun. 30, 2018	Jul. 01, 2017	May 29, 2018	Mar. 22, 2017	Mar. 03, 2017	Aug. 21, 2013
Property, Plant and Equipment
Restricted cash, current	$ 3.5	$ 7.3
Restricted cash, noncurrent	5.4	5.6
Advertising cost during the period	2.6	2.6	$ 2.1
Asset retirement obligations, current	0.4	0.7
Asset retirement obligations, noncurrent	$ 3.2	$ 3.0
Customer A - OSP customer \| Customer Concentration Risk \| Net Revenue
Property, Plant and Equipment
Concentration risk percentage, more than	10.00%	10.00%	10.00%
Building and improvements \| Minimum
Property, Plant and Equipment
Estimated useful lives	10 years
Building and improvements \| Maximum
Property, Plant and Equipment
Estimated useful lives	50 years
Machinery and equipment \| Minimum
Property, Plant and Equipment
Estimated useful lives	2 years
Machinery and equipment \| Maximum
Property, Plant and Equipment
Estimated useful lives	20 years
Furniture, fixtures, software and office equipment \| Minimum
Property, Plant and Equipment
Estimated useful lives	2 years
Furniture, fixtures, software and office equipment \| Maximum
Property, Plant and Equipment
Estimated useful lives	5 years
Software \| Minimum
Property, Plant and Equipment
Estimated useful lives	2 years
Software \| Maximum
Property, Plant and Equipment
Estimated useful lives	5 years
Office equipment \| Minimum
Property, Plant and Equipment
Estimated useful lives	2 years
Office equipment \| Maximum
Property, Plant and Equipment
Estimated useful lives	5 years
Demonstration units \| Minimum
Property, Plant and Equipment
Estimated useful lives	3 years
Demonstration units \| Maximum
Property, Plant and Equipment
Estimated useful lives	5 years
Convertible Debt \| 0.625% Senior Convertible Notes
Property, Plant and Equipment
Interest rate on senior convertible notes	0.625%	0.625%					0.625%
Convertible Debt \| 1.75% Senior Convertible Notes
Property, Plant and Equipment
Interest rate on senior convertible notes	1.75%	1.75%		1.75%
Convertible Debt \| 1.00% Senior Convertible Notes
Property, Plant and Equipment
Interest rate on senior convertible notes	1.00%	1.00%			1.00%	1.00%