Share-Based Payments - Summary of Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended	12 Months Ended
Jan. 31, 2024	Apr. 30, 2023
Total
Outstanding, beginning balance (in shares)	1,775,667
Granted (in shares)	419,730
Exercised (in shares)	(155,449)
Forfeited (in shares)	(40,750)
Canceled (in shares)	(41,285)
Expired (in shares)	(54,166)
Outstanding, ending balance (in shares)	1,903,747	1,775,667
Vested and expected to vest (in shares)	1,903,747
Exercisable (in shares)	1,457,113
Weighted Average Exercise Price
Outstanding, beginning balance (in dollars per share)	$ 4.80
Granted (in dollars per share)	6.10
Exercised (in dollars per share)	2.31
Forfeited (in dollars per share)	6.21
Canceled (in dollars per share)	4.44
Expired (in dollars per share)	12.78
Outstanding, ending balance (in dollars per share)	5.04	$ 4.80
Vested and expected to vest (in dollars per share)	5.04
Exercisable (in dollars per share)	$ 4.63
Weighted Average Remaining Contractual Life (Years)
Outstanding (in years)	5 years 4 months 24 days	4 years 7 months 6 days
Outstanding, granted (in years)	9 years 8 months 12 days
Vested and expected to vest (in years)	5 years 4 months 24 days
Exercisable (in years)	4 years 3 months 18 days
Aggregate Intrinsic Value
Outstanding	$ 3,068	$ 2,683
Vested and expected to vest	3,068
Exercisable	$ 3,011
Directors and Employees
Total
Outstanding, beginning balance (in shares)	1,739,336
Granted (in shares)	419,730
Exercised (in shares)	(155,449)
Forfeited (in shares)	(40,750)
Canceled (in shares)	(41,285)
Expired (in shares)	(54,166)
Outstanding, ending balance (in shares)	1,867,416	1,739,336
Vested and expected to vest (in shares)	1,867,416
Exercisable (in shares)	1,453,363
Non- Employees
Total
Outstanding, beginning balance (in shares)	36,331
Granted (in shares)	0
Exercised (in shares)	0
Forfeited (in shares)	0
Canceled (in shares)	0
Expired (in shares)	0
Outstanding, ending balance (in shares)	36,331	36,331
Vested and expected to vest (in shares)	36,331
Exercisable (in shares)	3,750

Share Based Compensation Arrangement by Share Based Payment Award, Aggregate Intrinsic Value

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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.

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

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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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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Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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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 price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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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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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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

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