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Commitments and Contingencies (Details) £ in Millions	3 Months Ended
Commitments and Contingencies (Details) £ in Millions	Sep. 29, 2018 USD ($)	Sep. 30, 2017 USD ($)	Sep. 29, 2018 GBP (£)	Jun. 30, 2018 USD ($)	Jul. 02, 2016 GBP (£)	Jun. 30, 2016 GBP (£)
Loss Contingencies [Line Items]
Guarantee liabilities	$ 0			$ 0
Standby letters of credit	$ 11,000,000
Product Warranties
Warranty Term for most products	3 years
Changes in warranty reserve
Balance as of beginning of period	$ 8,200,000	$ 5,800,000
Provision for warranty	400,000	500,000
Utilization of reserve	(1,200,000)	(900,000)
Adjustments related to pre-existing warranties (including changes in estimates)	1,600,000	700,000
Acquisition related	0	300,000
Balance as of end of period	9,000,000	$ 6,400,000
Performance bond
Loss Contingencies [Line Items]
Guarantee liabilities	1,600,000
Judicial ruling \| Case related to amendment of pension for foreign subsidiary
Loss Contingencies [Line Items]
Loss contingency accrual	$ 7,700,000		£ 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