Quarterly report pursuant to Section 13 or 15(d)

Stockholders' Equity (Schedule of Assumptions Used to Value Stock Options) (Details)

v3.19.2
Stockholders' Equity (Schedule of Assumptions Used to Value Stock Options) (Details) - Stock Incentive Plan and Stock Option Grants to Employees and Directors [Member]
3 Months Ended 12 Months Ended
Jul. 31, 2019
Apr. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Expected life (years) 3 years 3 years 6 months
Expected volatility 46.00% 50.10%
Risk-free interest rate 2.18% 2.63%
Dividend yield 0.00% 0.00%
Expected forfeiture rate