Schedule of Foreign Currency Forward Contracts (Detail) - Level 2 - USD ($) $ in Millions	Oct. 31, 2017	Jul. 31, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Foreign currency forward contracts asset	$ 0.1	$ 0.6
Total	$ 0.1	$ 0.6

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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