Fair Value of Financial Instruments and Long Term Debt - Carrying Value of Long-term Debt (Details) $ in Thousands	12 Months Ended
Apr. 30, 2026 USD ($) installment_payment	Apr. 30, 2025 USD ($) installment_payment
Debt Instrument
Finance lease obligations	$ 115,197	$ 108,920
Long-term debt	2,320,875
Debt issuance costs	(4,478)	(5,750)
Total	2,431,594	2,508,545
Less current maturities	101,357	94,925
Long-term debt and finance lease obligations, net of current maturities	$ 2,330,237	$ 2,413,620
Senior Notes \| 3.67% Senior Notes (Series A) due in 7 installments beginning June 17, 2022, and ending June 15, 2028
Debt Instrument
Interest rate	3.67%	3.67%
Number of payments \| installment_payment	7	7
Long-term debt	$ 63,000	$ 87,000
Senior Notes \| 3.75% Senior Notes (Series B) due in 7 installments beginning December 17, 2022 and ending December 18, 2028
Debt Instrument
Interest rate	3.75%	3.75%
Number of payments \| installment_payment	7	7
Long-term debt	$ 21,000	$ 29,000
Senior Notes \| 3.65% Senior Notes (Series C) due in 7 installments beginning May 2, 2025 and ending May 2, 2031
Debt Instrument
Interest rate	3.65%	3.65%
Number of payments \| installment_payment	7	7
Long-term debt	$ 45,000	$ 50,000
Senior Notes \| 3.72% Senior Notes (Series D) due in 7 installments beginning October 28, 2025 and ending October 28, 2031
Debt Instrument
Interest rate	3.72%	3.72%
Number of payments \| installment_payment	7	7
Long-term debt	$ 45,000	$ 50,000
Senior Notes \| 3.77% Senior Notes (Series F) due August 22, 2028
Debt Instrument
Interest rate	3.77%
Long-term debt	$ 250,000	250,000
Senior Notes \| 2.85% Senior Notes (Series G) due August 7, 2030
Debt Instrument
Interest rate	2.85%
Long-term debt	$ 325,000	325,000
Senior Notes \| 2.96% Senior Notes (Series H) due August 6, 2032
Debt Instrument
Interest rate	2.96%
Long-term debt	$ 325,000	325,000
Senior Notes \| Series I Senior Notes
Debt Instrument
Interest rate	5.23%
Long-term debt	$ 150,000	150,000
Senior Notes \| Series J Senior Notes
Debt Instrument
Interest rate	5.43%
Long-term debt	$ 100,000	100,000
Line of Credit \| Term Loan Facility
Debt Instrument
Long-term debt	200,000	200,000
Line of Credit \| Incremental Term Loan Facility
Debt Instrument
Long-term debt	$ 796,875	$ 839,375

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