Restructuring and related charges (Details) - Employee Severance [Member] $ in Thousands	9 Months Ended
May 30, 2020 USD ($)
Restructuring Cost and Reserve [Line Items]
Restructuring, Incurred cost	$ 1,400
Restructuring, Expected cost	6,300
Changes to the restructuring liability
Balance as of August 31, 2019	0
Charges	1,386
Cash payments	0
Non-cash settlements or adjustments	0
Balance as of May 30, 2020	$ 1,386

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

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Amount expected to be recognized in earnings for the specified restructuring cost.

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Discloses the amount charged against the accrued restructuring reserves, or earnings if not previously accrued, during the period for the specified type of restructuring cost.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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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.

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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

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Amount of expense (reversal of expense) which increases (decreases) the restructuring reserve from an adjustment to a previously accrued restructuring liability.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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