Schedule of Stock Option Activity (Details)	3 Months Ended
Jul. 31, 2022 $ / shares shares
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Shares underlying options outstanding, beginning	1,110,356
Weighted average exercise price, beginning balance \| $ / shares	$ 2.34
Weighted Average Remaining Contractual Term (In Years), Beginning	9 years 2 months 12 days
Shares underlying options outstanding, granted
Weighted Average Exercise Price, Granted \| $ / shares
Shares Underlying Options Outstanding, Exercised
Weighted Average Exercise Price, Exercised \| $ / shares
Shares Underlying Options Outstanding, Cancelled/forfeited	(37)
Weighted Average Exercise Price, Cancelled/forfeited \| $ / shares	$ 400.00
Shares underlying options outstanding, ending	1,110,319
Weighted average exercise price, ending balance \| $ / shares	$ 2.33
Weighted Average Remaining Contractual Term (In Years), Ending	8 years 10 months 24 days
Shares Underlying Options Outstanding, Exercisable at Ending	297,467
Weighted average exercise price, exercisable at ending \| $ / shares	$ 4.60
Weighted average remaining contractual term (in years), exercisable at ending	7 years 7 months 6 days
Performance Stock Options [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Shares underlying options outstanding, beginning	210,122
Weighted average exercise price, beginning balance \| $ / shares	$ 2.20
Weighted Average Remaining Contractual Term (In Years), Beginning	8 years 9 months 18 days
Shares underlying options outstanding, granted
Shares Underlying Options Outstanding, Exercised
Weighted Average Exercise Price, Exercised \| $ / shares
Shares Underlying Options Outstanding, Cancelled/forfeited
Weighted Average Exercise Price, Cancelled/forfeited \| $ / shares
Shares underlying options outstanding, ending	210,122
Weighted average exercise price, ending balance \| $ / shares	$ 2.20
Weighted Average Remaining Contractual Term (In Years), Ending	8 years 7 months 6 days
Shares Underlying Options Outstanding, Exercisable at Ending
Weighted average exercise price, exercisable at ending \| $ / shares

Weighted Average Remaining Contractual Term (In Years), Ending.

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)
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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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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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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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