Loans - Outstanding Pledged as Collateral (Details) - USD ($) $ in Thousands	Nov. 30, 2019	May 31, 2019
Pledging of Loans and Loans on Deposit
Restricted Cash and Cash Equivalents	$ 10,638	$ 8,282
Collateral trust bonds 2007 indenture
Pledging of Loans and Loans on Deposit
Loans outstanding and pledged as collateral	8,573,623	8,909,909
Secured Debt	7,322,711	7,622,711
Collateral trust bonds 1994 indenture
Pledging of Loans and Loans on Deposit
Secured Debt	35,000	40,000
Notes payable \| Federal Agricultural Mortgage Corporation
Pledging of Loans and Loans on Deposit
Secured Debt	3,094,954	3,054,914
Clean Renewable Energy Bonds Series 2009A
Pledging of Loans and Loans on Deposit
Secured Debt	9,225	9,225
Restricted Cash and Cash Equivalents	1,188	415
Assets Pledged as Collateral	10,944	10,764
Guaranteed Underwriter Program notes payable
Pledging of Loans and Loans on Deposit
Secured Debt	5,363,798	5,410,507
Mortgage notes \| Distribution system mortgage notes \| Collateral trust bonds 2007 indenture
Pledging of Loans and Loans on Deposit
Loans outstanding and pledged as collateral	8,442,063	8,775,231
Mortgage notes \| Distribution system mortgage notes \| Collateral trust bonds 1994 indenture
Pledging of Loans and Loans on Deposit
Loans outstanding and pledged as collateral	45,702	47,331
Mortgage notes \| Distribution and power supply system mortgage notes \| Federal Agricultural Mortgage Corporation
Pledging of Loans and Loans on Deposit
Loans outstanding and pledged as collateral	3,729,692	3,751,798
Mortgage notes \| Distribution and power supply system mortgage notes \| Clean Renewable Energy Bonds Series 2009A
Pledging of Loans and Loans on Deposit
Loans outstanding and pledged as collateral	9,756	10,349
Loans Guaranteed by Rural Utilities Service \| Collateral trust bonds 2007 indenture
Pledging of Loans and Loans on Deposit
Loans outstanding and pledged as collateral	131,560	134,678
Mortgage notes receivable on deposit \| Distribution and power supply system mortgage notes \| Federal Financing Bank
Pledging of Loans and Loans on Deposit
Loans outstanding and pledged as collateral	$ 6,090,864	$ 6,157,218

Carrying amount as of the balance sheet date of assets that have been pledged as collateral.

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- References

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Reflects the aggregate value of loans, trade receivables, securities and financial instruments that serve as collateral for obligations arising from a transfer of financial assets recorded as a secured borrowing.

+ References

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Amount of cash and cash equivalents restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

+ References

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