Loans Impaired Loans - Average Recorded Investment and Interest Income Recognized (Details) - USD ($) $ in Thousands	12 Months Ended
May 31, 2019	May 31, 2018	May 31, 2017
Impaired Loans
Total impaired loans	$ 12,183	$ 12,885	$ 14,349
Interest impaired loans	846	889	905
CFC
Impaired Loans
Total impaired loans	6,322	6,524	6,613
Interest impaired loans	553	571	562
RTFC
Impaired Loans
Total impaired loans	5,861	6,361	7,736
Interest impaired loans	$ 293	$ 318	$ 343

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- Definition

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5212-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5258-111524

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- Definition

Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

+ References

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