6. Equity Compensation Plans (Details - Option activity) - Equity Option [Member] shares in Thousands	9 Months Ended
Jan. 31, 2021 $ / shares shares
Number of Options
Number of Options Outstanding, Beginning \| shares	2,896
Number of Options Granted \| shares	893
Number of Options Exercised \| shares	(353)
Number of Options Cancelled or Expired \| shares	(105)
Number of Options Outstanding, Ending \| shares	3,331
Weighted Average Exercise Price
Weighted Average Exercise Price Outstanding, Beginning \| $ / shares	$ 6.20
Weighted Average Exercise Price Granted \| $ / shares	7.43
Weighted Average Exercise Price Exercised \| $ / shares	6.18
Weighted Average Exercise Price Canceled \| $ / shares	7.20
Weighted Average Exercise Price Outstanding, Ending \| $ / shares	$ 6.50

For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

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Weighted average price of options that were either forfeited or expired.

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Gross number of share options (or share units) granted during the period.

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Number of options outstanding, including both vested and non-vested options.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Number of share options (or share units) exercised during the current period.

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