Acquisitions - Vantage (Details) - USD ($) $ in Thousands		12 Months Ended
Sep. 26, 2016	Jul. 31, 2017
Vantage
Business Acquisition [Line Items]
Total consideration for the transaction, excluding acquisition-related costs	$ 4,044	$ 4,044

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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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration