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, 2026	May 31, 2025
Maturity Amount
Total	$ 1,310,282	$ 1,329,485
Members' certificates, exclusive of certificates amortized annually
Maturity Amount
2027	3,484
2027	4,502
2029	6,265
2030	4,384
2031	64,558
Thereafter	1,045,029
Total	$ 1,128,222
Weighted-Average Interest Rate
2027	3.40%
2027	3.54%
2029	2.49%
2030	3.71%
2031	3.31%
Thereafter	4.64%
Total	4.54%
Loan subordinated certificates
Maturity Amount
Total	$ 227,031	$ 283,157
Other information
Payments not received on certificates subscribed and unissued	20
Average amortization of debt	$ 7,000
Amortization as a percentage of amortizing loan subordinated debt outstanding	6.00%
Amortizing member loan subordinated certificates
Maturity Amount
Total	$ 114,000

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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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