Fair Value of Financial Instruments and Long Term Debt - Schedule of Maturities of Long-Term Debt Including Capitalizied Leases (Details) $ in Thousands	Apr. 30, 2020 USD ($)
Finance Leases
2021	$ 2,244
2022	2,354
2023	2,484
2024	2,060
2025	734
Thereafter	6,870
Finance Leases	16,746
Senior Notes
2021	569,000
2022	0
2023	20,000
2024	32,000
2025	32,000
Thereafter	616,000
Senior Notes	1,269,000
Total
2021	571,244
2022	2,354
2023	22,484
2024	34,060
2025	32,734
Thereafter	622,870
Total	$ 1,285,746

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