Fair Value of Financial Instruments and Long Term Debt - Schedule of Maturities of Long-Term Debt Including Capitalizied Leases (Details) - USD ($) $ in Thousands	Apr. 30, 2021	Apr. 30, 2020
Finance Leases
2022	$ 2,354
2023	2,484
2024	2,060
2025	734
2026	471
Thereafter	5,982
Finance Leases	14,085	$ 16,746
Senior Notes
2022	0
2023	20,000
2024	32,000
2025	32,000
2026	192,000
Thereafter	1,074,000
Senior Notes	1,350,000
Total
2022	2,354
2023	22,484
2024	34,060
2025	32,734
2026	192,471
Thereafter	1,079,982
Total	$ 1,364,085

Finance Lease Payments Due And Long Term Debt Maturities [Abstract]

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Present value of lessee's discounted obligation for lease payments from finance lease.

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