Property plant and equipment - New ERP System (Details) - USD ($) $ in Millions	12 Months Ended
Jun. 29, 2019	Jun. 30, 2018
ERP System \| Restructuring Integration And Other Expenses
Change in Accounting Estimate [Line Items]
Accelerated depreciation	$ 11.3	$ 52.9

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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