Derivatives and Hedging Activities - Fair Values of Derivative Instruments in Consolidated Balance Sheets (Detail) - USD ($) $ in Thousands	Apr. 30, 2021	Jul. 31, 2020
Prepaid expenses and other current assets [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives	$ 724	$ 594
Other current liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives	252	777
Designated as Hedging Instrument [Member] | Unrealized (loss) gain on cash flow hedges | Prepaid expenses and other current assets [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives	724	588
Designated as Hedging Instrument [Member] | Unrealized (loss) gain on cash flow hedges | Other current liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives	242	761
Not designated as hedging Instruments [Member] | Unrealized (loss) gain on cash flow hedges | Prepaid expenses and other current assets [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives	0	6
Not designated as hedging Instruments [Member] | Unrealized (loss) gain on cash flow hedges | Other current liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives	$ 10	$ 16