FAIR VALUE MEASUREMENTS - Financial Assets Measured at Fair Value on Recurring Basis and Classified by Fair Value Hierarchy (Details) - Fair value, measurements, recurring - Money market funds - USD ($) $ in Thousands	Apr. 30, 2022	Jul. 31, 2021
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value disclosure, recurring	$ 34,324	$ 37,320
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value disclosure, recurring	34,324	37,320
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