Schedule of Stock Option Activity (Details) - $ / shares	9 Months Ended
Jan. 31, 2023
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	$ 2.34
Weighted Average Remaining Contractual Term (In Years), Beginning	9 years 2 months 12 days
Shares underlying Options Outstanding, Granted	601,089
Weighted Average Exercise Price, Granted	$ 0.68
Shares Underlying Options ,Exercised
Weighted Average Exercise Price, Exercised
Shares Underlying Options, Cancelled/forfeited	(135,903)
Weighted Average Exercise Price, Cancelled/forfeited	$ 1.88
Shares Underlying Options, ending	1,575,542
Weighted average exercise price, ending balance	$ 1.75
Weighted Average Remaining Contractual Term (In Years), Ending	9 years
Shares Underlying Options, Exercisable at Ending	540,546
Weighted Average Exercise Price, Exercisable at ending	$ 3.19
Weighted Average Remaining Contractual Term (In Years), Exercisable at Ending	7 years 10 months 24 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	$ 2.20
Weighted Average Remaining Contractual Term (In Years), Beginning	8 years 9 months 18 days
Shares underlying Options Outstanding, Granted
Weighted Average Exercise Price, Granted
Shares Underlying Options ,Exercised
Weighted Average Exercise Price, Exercised
Shares Underlying Options, Cancelled/forfeited	(8,466)
Weighted Average Exercise Price, Cancelled/forfeited	$ 2.93
Shares Underlying Options, ending	201,656
Weighted average exercise price, ending balance	$ 2.17
Weighted Average Remaining Contractual Term (In Years), Ending	8 years 1 month 6 days
Shares Underlying Options, Exercisable at Ending
Weighted Average Exercise Price, Exercisable at ending

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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- Definition

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

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- Definition

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

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- Definition

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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- Definition

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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-Topic 718
-SubTopic 10
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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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- Definition

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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-Name Accounting Standards Codification
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