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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=28368275&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 17

-URI http://asc.fasb.org/extlink&oid=28368275&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.

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- Definition

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://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 14A

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=28368275&loc=SL6953550-111524

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Amount of allowance for credit losses related to recorded investment.

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Amount of investment in impaired financing receivables for which there is no related allowance for credit losses.

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Amount of investment in impaired financing receivables for which there is a related allowance for credit losses.

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Reflects the amount of additional interest income that would have been recorded if impaired or nonperforming loans were instead current, in compliance with their original terms, and outstanding throughout the reporting period or since origination (if held for part of the period).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 40

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=25495931&loc=d3e18794-111554

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Loans and Commitments (Details 6) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Feb. 28, 2014	Feb. 28, 2013	Feb. 28, 2014	Feb. 28, 2013	May 31, 2013
Recorded investment in individually-impaired loans and the related specific valuation allowance
With no specific allowance recorded	$ 16,164		$ 16,164		$ 51,953
With a specific allowance recorded	2,265		2,265		10,497
Total impaired loans	18,429		18,429		62,450
Related allowance	0		0		0
Average recorded investment
Total impaired loans	18,565	81,608	24,825	220,300
Interest income recognized
Interest impaired loans	0	435	136	13,522
Interest income reduction as a result of holding loans on non-accrual status
Interest income reduced	242	355	807	1,135
CFC \| Distribution
Recorded investment in individually-impaired loans and the related specific valuation allowance
With no specific allowance recorded	7,584		7,584		46,953
Related allowance	0		0		0
Average recorded investment
Total impaired loans	7,584	70,111	11,939	208,632
Interest income recognized
Interest impaired loans	0	435	136	13,522
CFC \| Power Supply
Recorded investment in individually-impaired loans and the related specific valuation allowance
With no specific allowance recorded	5,000		5,000		5,000
Related allowance	0		0		0
Average recorded investment
Total impaired loans	5,000	5,000	5,000	5,000
Interest income recognized
Interest impaired loans	0	0	0	0
RTFC
Recorded investment in individually-impaired loans and the related specific valuation allowance
With no specific allowance recorded	3,580		3,580		0
With a specific allowance recorded	1,815		1,815		10,497
Related allowance	0		0		0
Average recorded investment
Total impaired loans	5,527	6,497	7,735	6,668
Interest income recognized
Interest impaired loans	0	0	0	0
National Cooperative Services Corporation [Member]
Recorded investment in individually-impaired loans and the related specific valuation allowance
With a specific allowance recorded	450		450
Related allowance	55		55
Average recorded investment
Total impaired loans	454	0	151	0
Interest income recognized
Interest impaired loans	0	0	0	0
Non-performing loans
Interest income reduction as a result of holding loans on non-accrual status
Interest income reduced	120	355	440	1,135
Restructured loans
Interest income reduction as a result of holding loans on non-accrual status
Interest income reduced	$ 122	$ 0	$ 367	$ 0