Members' Subordinated Certificates - Schedule of amount of members' subordinated certificates maturing in each of the five fiscal years (Details) - USD ($) $ in Thousands	12 Months Ended
May 31, 2023	May 31, 2022
Amount Maturing
Total long-term debt	$ 1,283,436	$ 986,518
Members' certificates, exclusive of certificates amortized annually
Amount Maturing
2024	5,861
2025	7,481
2026	63,078
2027	8,052
2028	5,487
Thereafter	1,133,107
Total long-term debt	$ 1,223,066
Weighted-Average Interest Rate
2024	2.22%
2025	2.71%
2026	3.24%
2027	2.00%
2028	3.04%
Thereafter	4.49%
Total (as a percent)	4.38%
Loan subordinated certificates
Amount Maturing
Total long-term debt	$ 321,211	$ 338,055
Other information
Payments not received on certificates subscribed and unissued	60
Average amortization of debt	$ 12,000
Amortization as a percentage of amortizing loan subordinated debt outstanding	8.00%
Amortizing member loan subordinated certificates
Amount Maturing
Total long-term debt	$ 159,000

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Represents the weighted average interest rate of the amount of long-term debt maturing after the fifth fiscal year following the latest fiscal year.

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Represents the weighted average interest rate of the amount of long-term debt maturing in the fifth fiscal year following the latest fiscal year.

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Represents the weighted average interest rate of the amount of long-term debt maturing in the fourth fiscal year following the latest fiscal year.

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Represents the weighted average interest rate of the amount of long-term debt maturing in the first fiscal year following the latest fiscal year.

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Represents the weighted average interest rate of the amount of long-term debt maturing in the third fiscal year following the latest fiscal year.

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Represents the weighted average interest rate of the amount of long-term debt maturing in the second fiscal year following the latest fiscal year.

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Represents the amortization as a percentage of subordinated debt outstanding.

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Represents the annual average amortized amount of the subordinated debt.

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Represents the amount not received on certificates subscribed and unissued.

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Carrying value as of the balance sheet date of collateralized/uncollateralized debt obligation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion. Subordinated debt places a lender in a lien position behind the primary lender of the company.

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