Fair Value Measurements - Financial Assets and Liabilities Accounted for at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Oct. 31, 2019	Jul. 31, 2019
Fair Value, Inputs, Level 1 [Member] \| Other Assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading securities	$ 15,212	$ 15,744
Fair Value, Inputs, Level 2 [Member] \| Prepaid expenses and other current assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Foreign exchange contracts	595	474
Fair Value, Inputs, Level 2 [Member] \| Other current liabilities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Foreign exchange contracts	$ 12	$ 5

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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- Definition

Fair value portion of asset contracts related to the exchange of different currencies, including, but not limited to, foreign currency options, forward contracts, and swaps.

+ References

No definition available.

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- Definition

Fair value portion of liability contracts related to the exchange of different currencies, including, but not limited to, foreign currency options, forward (delivery or nondelivery) contracts, and swaps entered into.

+ References

No definition available.

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- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading) and investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.4)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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