Long-Term Debt - Schedule of Long-term Debt, at Amortized Cost (Detail) - USD ($) $ in Thousands	Apr. 30, 2023	Apr. 30, 2022
Debt Instrument [Line Items]
Long-term borrowings, net of unamortized discount and debt issuance costs	$ 396,194	$ 395,477
4.625% Senior Unsecured Notes due 2027
Debt Instrument [Line Items]
Less: Unamortized discount and issuance costs	(3,806)	(4,523)
Long-term borrowings, net of unamortized discount and debt issuance costs	396,194	395,477
4.625% Senior Unsecured Notes due 2027 \| Senior Unsecured Notes
Debt Instrument [Line Items]
Senior Unsecured Notes	$ 400,000	$ 400,000

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Amount of unamortized debt discount (premium) and debt issuance costs.

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Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt classified as noncurrent. Excludes lease obligation.

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