REVENUE RECOGNITION - Performance Obligations (Details) $ in Millions	Jul. 31, 2019 USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-08-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Unearned revenue	$ 2.9
Unearned revenue, timing of satisfaction	12 years
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-08-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Unearned revenue	$ 0.1
Unearned revenue, timing of satisfaction