Share Incentive Plan - Summary of Information Related to Share Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Apr. 30, 2022	Apr. 30, 2021	Apr. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Beginning balance (in shares)	14,120,179	10,776,188
Options granted (in shares)	701,500	6,325,510
Options exercised and vested (in shares)	(2,924,410)	(2,468,792)
Options canceled/forfeited (in shares)	(536,524)	(512,727)
Ending balance (in shares)	11,360,745	14,120,179	10,776,188
Options vested or expected to vest (in shares)	11,360,745
Options exercisable (in shares)	10,934,625
Weighted-Average Exercise Price
Beginning balance (in US dollars per share)	$ 1.57	$ 0.67
Options granted (in US dollars per share)	6.11	2.70
Options exercised and vested (in US dollars per share)	1.04	0.56
Options canceled/forfeited (in US dollars per share)	3.18	1.72
Ending balance (in US dollars per share)	1.94	$ 1.57	$ 0.67
Options vested or expected to vest (in US dollars per share)	1.94
Options exercisable (in US dollars per share)	$ 1.94
Weighted-Average Remaining Contractual Term and Aggregate Intrinsic Value
Weighted-average remaining contractual term, options outstanding	7 years 1 month 13 days	7 years 10 months 13 days	7 years 6 months 10 days
Weighted-average remaining contractual term, options vested or expected to vest	7 years 1 month 13 days
Weighted-average remaining contractual term, options exercisable	7 years 1 month 13 days
Aggregate intrinsic value, options outstanding, beginning balance	$ 62,613	$ 15,592
Aggregate intrinsic value, options outstanding, ending balance	103,412	$ 62,613	$ 15,592
Aggregate intrinsic value, options vested or expected to vest	103,412
Aggregate intrinsic value, options exercisable	$ 99,497

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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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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 exercisable or convertible options. 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 exercisable options that may 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 exercisable or convertible options. 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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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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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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Weighted average remaining contractual term for fully vested and expected to vest exercisable or convertible options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. 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 remaining contractual term for fully vested and expected to vest options outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. 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 share options (or share units) exercised during the current period.

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