Fair value measurements - Carrying Amounts and Fair Values of Financial Instruments, Other than Cash and Cash Equivalents, Receivables and Accounts Payable (Detail) - USD ($) $ in Thousands	Apr. 30, 2026	Apr. 30, 2025
Fair Value Disclosures [Abstract]
Long-term debt, carrying amount	$ 1,879,952	$ 1,996,254
Long-term debt, fair value	$ 1,910,744	$ 2,038,869

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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+ Details

- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

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+ Details