Shareholders' Equity - Summary of Changes in Outstanding Options (Details) - USD ($)	12 Months Ended
Apr. 30, 2022	Apr. 30, 2021	Apr. 30, 2020
Number of Shares
Outstanding at May 1, 2020 (in shares)	4,109,733
Granted (in shares)	1,458,500
Exercised (in shares)	(776,129)	(628,917)	(1,020,910)
Forfeited (in shares)	(245,000)
Expired (in shares)	(7,000)
Outstanding at April 30, 2021 (in shares)	4,540,104	4,109,733
Weighted Average Exercise Price
Outstanding at May 1, 2020 (in usd per share)	$ 13.33
Granted (in usd per share)	21.54
Exercised (in usd per share)	11.06
Forfeited (in usd per share)	19.24
Expired (in usd per share)	9.69
Outstanding at April 30, 2021 (in usd per share)	16.05	$ 13.33
Exercisable at April 30, 2022 (in usd per share)	$ 13.43
Weighted Average Remaining Contractual Term
Outstanding at April 30, 2021	3 years 8 months 12 days
Exercisable at April 30, 2022	2 years 7 months 6 days
Aggregate Intrinsic Value
Outstanding at April 30, 2021	$ 10,585,462
Exercisable at April 30, 2022	$ 4,945,472

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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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Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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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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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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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 price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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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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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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