Compensation Related Costs and Share Based Payments - Narrative (Details) - USD ($) $ in Thousands	6 Months Ended
Oct. 31, 2024	Oct. 31, 2023
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award
Number of shares available for grant reduction per stock option issued (in shares)	1
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award
Number of shares available for grant reduction per equity instruments other options issued (in shares)	2
Stock Incentive Plans \| Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award
Performance measurement period	3 years
Downward adjustment percentage	25.00%
Upward adjustment percentage	25.00%
Allocated share-based compensation expense	$ 23,645	$ 19,485
Unrecognized compensation costs related to plan	$ 56,444
Unrecognized compensation costs, weighted average remaining term	1 year 3 months 18 days
Fair value of shares vested	$ 64,615
Stock Incentive Plans \| Restricted Stock Units \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award
Target percentage	0.00%
Stock Incentive Plans \| Restricted Stock Units \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award
Target percentage	200.00%
2018 Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award
Number of shares available for grant (in shares)	950,954
Granted (in shares)	0

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Share-based Compensation Arrangement by Share-based Payment Award, Percent Of Targeted Award

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Share-based Compensation Arrangement By Share-based Payment Award, Number Of Shares Available For Grant Reduction Per Stock Option Issued

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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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.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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

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