Intangible Assets, Goodwill and Long-Lived Assets - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
Jul. 31, 2019	Jul. 31, 2018	Jul. 31, 2017
Intangible Assets And Goodwill [Line Items]
Pre-tax, non-cash goodwill impairment charge	$ 0	$ 0	$ 0

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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