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Equity-Based Compensation (Details) - USD ($) $ in Thousands, shares in Millions	12 Months Ended
	Apr. 30, 2021	Apr. 30, 2020	Apr. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation	$ 8,442	$ 7,060	$ 3,906
Selling, general and administrative expenses
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation	$ 7,900	$ 6,500	$ 3,600
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Term of award	ten years
Minimum \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	3 years
Minimum \| Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	1 year
Maximum \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	4 years
Maximum \| Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	3 years
Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized	2.4
Number of shares available for grant	2.4