Commitments and Contingencies (Details) £ in Millions	3 Months Ended		6 Months Ended
	Dec. 29, 2018 USD ($)	Dec. 30, 2017 USD ($)	Dec. 29, 2018 USD ($)	Dec. 30, 2017 USD ($)	Dec. 29, 2018 GBP (£)	Jun. 30, 2018 USD ($)	Jul. 02, 2016 GBP (£)	Jun. 30, 2016 GBP (£)
Loss Contingencies [Line Items]
Guarantee liabilities	$ 0		$ 0			$ 0
Charge to discontinued operations	2,400,000	$ 0	2,400,000	$ 0
Standby letters of credit	11,000,000		$ 11,000,000
Product Warranties
Warranty Term for most products			3 years
Changes in warranty reserve
Balance as of beginning of period	9,000,000	6,400,000	$ 8,200,000	5,800,000
Provision for warranty	1,000,000	1,700,000	1,400,000	2,200,000
Utilization of reserve	(1,500,000)	(2,600,000)	(2,700,000)	(3,500,000)
Adjustments related to pre-existing warranties (including changes in estimates)	700,000	1,300,000	2,300,000	2,000,000
Acquisition related	0	0	0	300,000
Balance as of end of period	9,200,000	$ 6,800,000	9,200,000	$ 6,800,000
Performance bond
Loss Contingencies [Line Items]
Guarantee liabilities	1,500,000		1,500,000
Judicial ruling | Case related to amendment of pension for foreign subsidiary
Loss Contingencies [Line Items]
Loss contingency accrual	7,500,000		$ 7,500,000		£ 5.9
Minimum | Judicial ruling | Case related to amendment of pension for foreign subsidiary
Loss Contingencies [Line Items]
Estimated liability | £								£ 5.7
Loss contingency accrual | £							£ 5.7
Maximum | Judicial ruling | Case related to amendment of pension for foreign subsidiary
Loss Contingencies [Line Items]
Estimated liability | £								£ 8.4
Spinoff | Lumentum
Loss Contingencies [Line Items]
Charge to discontinued operations	$ 2,400,000