Acquisitions - BHT Group (Details) - USD ($) $ in Thousands		9 Months Ended
Aug. 23, 2017	Apr. 30, 2018
BHT Group
Business Acquisition [Line Items]
Total consideration for the transaction, excluding acquisition-related costs	$ 60,787	$ 60,787

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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