FAIR VALUE MEASUREMENTS - Financial Assets Measured at Fair Value on Recurring Basis and Classified by Fair Value Hierarchy (Detail) - Fair value, measurements, recurring - Money market funds - USD ($) $ in Thousands	Jan. 31, 2021	Jul. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value disclosure, recurring	$ 45,121	$ 5,117
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value disclosure, recurring	45,121	5,117
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value disclosure, recurring	0	0
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value disclosure, recurring	$ 0	$ 0