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Fair Value Measurements (Tables) | 9 Months Ended
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Jan. 31, 2021
Fair Value Disclosures [Abstract] |
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions | The Company determined the fair value using the Black-Scholes option pricing model with the following assumptions:
|  | January 31, 2021 |  |  | January 31, 2020 |
Dividend rate |  |  | 0.0 | % |  |  | 0.0 | %
Risk-free rate |  |  | 0.07% - 0.08 | % |  |  | 1.5 | %
Expected life (years) |  |  | 0.5 - 0.8 |  |  |  | 1.3 - 1.4 |
Expected volatility |  |  | 146.1 | % |  |  | 109.8% - 130.1 | %

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- Definition Tabular disclosure of the significant assumptions used during the year to estimate the fair value of stock options, including, but not limited to: (a) expected term of share options and similar instruments, (b) expected volatility of the entity's shares, (c) expected dividends, (d) risk-free rate(s), and (e) discount for post-vesting restrictions. + References No definition available. + Details
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- References No definition available. + Details
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