XML 49 R55.htm IDEA: XBRL DOCUMENT v3.19.3.a.u2
EQUITY AWARD PLANS - ESPP (Details) - Employee Stock Purchase Plan
6 Months Ended
Jan. 31, 2020
Jan. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Expected term (in years) 28 days 24 days
Risk-free interest rate 1.90% 2.50%
Volatility 68.70% 49.50%
Dividend yield 0.00% 0.00%