Long-Term Debt - Long-Term Debt Outstanding (Details) - USD ($) $ in Thousands	Feb. 28, 2022	May 31, 2021
Long-term debt
Long-term debt	$ 21,521,734	$ 20,603,123
Collateral trust bonds
Long-term debt
Long-term debt, gross	7,547,711	7,452,711
Unamortized discount	(219,775)	(227,046)
Debt issuance costs	(33,787)	(33,721)
Long-term debt	7,294,149	7,191,944
Guaranteed Underwriter Program notes payable
Long-term debt
Long-term debt	6,149,203	6,269,303
Farmer Mac notes payable
Long-term debt
Long-term debt	3,018,130	2,977,909
Other secured notes payable
Long-term debt
Long-term debt, gross	2,755	4,412
Debt issuance costs	(11)	(22)
Long-term debt	2,744	4,390
Notes payable
Long-term debt
Long-term debt	9,170,077	9,251,602
Secured debt
Long-term debt
Long-term debt	16,464,226	16,443,546
Medium-term notes sold through dealers
Long-term debt
Long-term debt, gross	4,891,283	3,943,728
Medium-term notes sold to members
Long-term debt
Long-term debt, gross	186,104	232,346
Medium term notes sold through dealers and to members
Long-term debt
Long-term debt, gross	5,077,387	4,176,074
Unamortized discount	(2,155)	(2,307)
Debt issuance costs	(19,687)	(18,036)
Long-term debt	5,055,545	4,155,731
Other unsecured notes payable
Long-term debt
Long-term debt, gross	1,979	3,886
Unamortized discount	(14)	(35)
Debt issuance costs	(2)	(5)
Total other unsecured notes payable
Long-term debt
Long-term debt	1,963	3,846
Unsecured debt
Long-term debt
Long-term debt	$ 5,057,508	$ 4,159,577

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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