National Rural Utilities Cooper (NRUC) 10-Q 10 Oct 19 2020 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information	3 Months Ended
	Aug. 31, 2019shares
Document and Entity Information
Entity Registrant Name	NATIONAL RURAL UTILITIES COOPERATIVE FINANCE CORP /DC/
Entity Central Index Key	0000070502
Document Type	10-Q
Document Period End Date	Aug. 31, 2019
Amendment Flag	false
Current Fiscal Year End Date	--05-31
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding	0
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q1
Entity Small Business	false
Entity Emerging Growth Company	false

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations (Unaudited) - USD ($) $ in Thousands		3 Months Ended
		Aug. 31, 2019	Aug. 31, 2018
Income Statement [Abstract]
Interest income		$ 290,015	$ 278,491
Interest expense	[1],[2]	(213,271)	(210,231)
Net interest income		76,744	68,260
Benefit (provision) for loan losses		(30)	109
Net interest income after benefit (provision) for loan losses		76,714	68,369
Non-interest income:
Fee and other income		10,941	3,911
Derivative gains (losses)		(395,725)	7,183
Unrealized gains (losses) on equity securities		1,620	(726)
Total non-interest income		(383,164)	10,368
Non-interest expense:
Salaries and employee benefits		(12,942)	(12,682)
Other general and administrative expenses		(12,387)	(10,523)
Losses on early extinguishment of debt		0	(7,100)
Other non-interest (expense) income		7,179	(394)
Total non-interest expense		(18,150)	(30,699)
Income (loss) before income taxes		(324,600)	48,038
Income tax benefit (expense)		521	(60)
Net income (loss)		(324,079)	47,978
Less: Net (income) loss attributable to noncontrolling interests		1,657	(13)
Net income (loss) attributable to CFC		$ (322,422)	$ 47,965
[1]	Includes amortization of debt discounts and debt issuance costs, which are generally deferred and recognized as interest expense using the effective interest method. Issuance costs related to dealer commercial paper, however, are recognized as interest expense immediately as incurred.
[2]	Includes fees related to funding arrangements, such as up-front fees paid to banks participating in our committed bank revolving line of credit agreements. Depending on the nature of the fee, amounts may be deferred and recognized as interest expense ratably over the term of the arrangement or recognized immediately as incurred.

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive Income (Loss) (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Aug. 31, 2019	Aug. 31, 2018
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ (324,079)	$ 47,978
Other comprehensive income (loss):
Unrealized gains on cash flow hedge	0	24
Reclassification of derivative gains to net income	(112)	(119)
Defined benefit plan adjustments	145	131
Other comprehensive income (loss)	33	36
Total comprehensive income (loss)	(324,046)	48,014
Less: Total comprehensive (income) loss attributable to noncontrolling interests	1,657	(13)
Total comprehensive income (loss) attributable to CFC	$ (322,389)	$ 48,001

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Aug. 31, 2019	May 31, 2019
Assets:
Cash and cash equivalents	$ 231,050	$ 177,922
Restricted cash	9,138	8,282
Total cash, cash equivalents and restricted cash	240,188	186,204
Investment securities:
Equity securities	63,922	87,533
Debt securities held-to-maturity, at amortized cost	569,575	565,444
Total investment securities	633,497	652,977
Loans to members	26,299,838	25,916,904
Less: Allowance for loan losses	(17,565)	(17,535)
Loans to members, net	26,282,273	25,899,369
Accrued interest receivable	133,119	133,605
Other receivables	35,878	36,712
Fixed assets, net	121,692	120,627
Derivative assets	85,533	41,179
Other assets	46,576	53,699
Total assets	27,578,756	27,124,372
Liabilities:
Accrued interest payable	209,931	158,997
Debt outstanding:
Short-term borrowings	4,027,645	3,607,726
Long-term debt	19,094,236	19,210,793
Subordinated deferrable debt	985,981	986,020
Members’ subordinated certificates:
Membership subordinated certificates	630,474	630,474
Loan and guarantee subordinated certificates	504,841	505,485
Member capital securities	221,170	221,170
Total members’ subordinated certificates	1,356,485	1,357,129
Total debt outstanding	25,464,347	25,161,668
Patronage capital retirement payable	61,102	0
Deferred income	55,614	57,989
Derivative liabilities	820,872	391,724
Other liabilities	48,462	50,112
Total liabilities	26,660,328	25,820,490
CFC equity:
Retained equity	891,332	1,276,882
Accumulated other comprehensive income	(114)	(147)
Total CFC equity	891,218	1,276,735
Noncontrolling interests	27,210	27,147
Total equity	918,428	1,303,882
Total liabilities and equity	$ 27,578,756	$ 27,124,372

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Changes in Equity (Unaudited) - USD ($) $ in Thousands	Total	Non-controlling Interests	Total CFC Equity	Accumulated Other Comprehensive Income (Loss)	CFC Retained Equity	Unallocated Net Income (Loss)	Members’ Capital Reserve	Patronage Capital Allocated	Membership Fees and Educational Fund
Cumulative effect from adoption of new accounting standard				$ (8,794)	$ 8,794	$ 8,794
Balance as of June 1, 2018	$ 1,505,853	$ 31,520	$ 1,474,333	(250)	1,474,583	(27,640)	$ 687,785	$ 811,493	$ 2,945
Balance at May. 31, 2018	1,505,853	31,520	1,474,333	8,544	1,465,789	(36,434)	687,785	811,493	2,945
Net income (loss)	47,978	13	47,965		47,965	47,965
Other comprehensive income	36		36	36
Patronage capital retirement	(47,507)		(47,507)		(47,507)	0		(47,507)
Other	216	552	(336)		(336)				(336)
Balance at Aug. 31, 2018	1,506,576	32,085	1,474,491	(214)	1,474,705	20,325	687,785	763,986	2,609
Balance at May. 31, 2019	1,303,882	27,147	1,276,735	(147)	1,276,882	(345,775)	759,097	860,578	2,982
Net income (loss)	(324,079)	(1,657)	(322,422)		(322,422)	(322,422)
Other comprehensive income	33		33	33	0	0
Patronage capital retirement	(62,822)	0	(62,822)		(62,822)			(62,822)
Other	1,414	1,720	(306)		(306)				(306)
Balance at Aug. 31, 2019	$ 918,428	$ 27,210	$ 891,218	$ (114)	$ 891,332	$ (668,197)	$ 759,097	$ 797,756	$ 2,676

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Aug. 31, 2019	Aug. 31, 2018
Cash flows from operating activities:
Net income (loss)	$ (324,079)	$ 47,978
Adjustments to reconcile net income to net cash provided by operating activities:
Amortization of deferred loan fees	(2,332)	(2,609)
Amortization of debt issuance costs and deferred charges	2,357	3,003
Amortization of discount on long-term debt	2,626	2,802
Amortization of issuance costs for bank revolving lines of credit	1,268	1,328
Depreciation and amortization	2,374	2,230
Provision (benefit) for loan losses	30	(109)
Loss on early extinguishment of debt	0	7,100
Gain on sale of land	(7,713)	0
Unrealized losses on equity securities	(1,620)	726
Derivative forward value (gains) losses	384,682	(20,012)
Changes in operating assets and liabilities:
Accrued interest receivable	485	3,099
Accrued interest payable	50,934	56,614
Deferred income	(43)	398
Other	(9,160)	(20,818)
Net cash provided by operating activities	99,809	81,730
Cash flows from investing activities:
Advances on loans, net	(382,936)	(3,942)
Investment in fixed assets	(3,087)	(4,253)
Proceeds from sale of land	21,618	0
Net proceeds from time deposits	0	100,000
Proceeds from Sale and Maturity of Debt and Equity Securities, FV-NI, Held-for-investment	25,000	0
Purchases of held-to-maturity debt securities	(23,650)	(40,684)
Proceeds from maturities of held-to-maturity debt securities	19,533	7,339
Net cash provided by (used in) investing activities	(343,522)	58,460
Cash flows from financing activities:
Proceeds from short-term borrowings, net	355,750	29,246
Proceeds from short-term borrowings with original maturity greater than 90 days	679,062	296,242
Repayments of short term-debt with original maturity greater than 90 days	(614,892)	(328,262)
Proceeds from issuance of long-term debt, net of discount and issuance costs	94,256	349,509
Payments for retirement of long-term debt	(215,751)	(395,284)
Payments made for early extinguishment of debt	0	(7,100)
Payments for issuance costs for subordinated deferrable debt	(84)	0
Proceeds from issuance of members’ subordinated certificates	1,289	471
Payments for retirement of members’ subordinated certificates	(1,933)	(2,378)
Payments for retirement of patronage capital	0	(46,956)
Net cash provided by (used in) financing activities	297,697	(104,512)
Net increase in cash, cash equivalents and restricted cash	53,984	35,678
Beginning cash, cash equivalents and restricted cash	186,204	238,824
Ending cash, cash equivalents and restricted cash	240,188	274,502
Supplemental disclosure of cash flow information:
Cash paid for interest	$ 155,330	$ 148,063

Summary of Significant Accounti

Summary of Significant Accounting Policies - (Notes)	3 Months Ended
	Aug. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Summary of Significant Accounting Policies	NOTE 1—SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES The Company National Rural Utilities Cooperative Finance Corporation (“CFC”) is a member-owned cooperative association incorporated under the laws of the District of Columbia in April 1969. CFC’s principal purpose is to provide its members with financing to supplement the loan programs of the Rural Utilities Service (“RUS”) of the United States Department of Agriculture (“USDA”). CFC makes loans to its rural electric members so they can acquire, construct and operate electric distribution systems, generation and transmission (“power supply”) systems and related facilities. CFC also provides its members with credit enhancements in the form of letters of credit and guarantees of debt obligations. As a cooperative, CFC is owned by and exclusively serves its membership, which consists of not-for-profit entities or subsidiaries or affiliates of not-for-profit entities. CFC is exempt from federal income taxes. Basis of Presentation and Use of Estimates The accompanying unaudited interim condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States (“GAAP”). The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts and related disclosures during the period. Management’s most significant estimates and assumptions involve determining the allowance for loan losses and the fair value of financial assets and liabilities. Actual results could differ from these estimates. We believe these financial statements reflect all adjustments of a normal, recurring nature that are, in the opinion of management, necessary for the fair presentation of the results for the interim period. The results of operations for interim periods are not necessarily indicative of results for the entire fiscal year. Certain reclassifications have been made to prior periods to conform to the current presentation. The accompanying financial statements should be read in conjunction with the audited consolidated financial statements, and related notes thereto, included in CFC’s Annual Report on Form 10-K for the fiscal year ended May 31, 2019 (“ 2019 Form 10-K”). Refer to “Note 1—Summary of Significant Accounting Policies” in our 2019 Form 10-K for a discussion of our significant accounting policies. Principles of Consolidation The accompanying condensed consolidated financial statements include the accounts of CFC, variable interest entities (“VIEs”) where CFC is the primary beneficiary and subsidiary entities created and controlled by CFC to hold foreclosed assets. CFC did no t have any entities that held foreclosed assets as of August 31, 2019 or May 31, 2019 . All intercompany balances and transactions have been eliminated. National Cooperative Services Corporation (“NCSC”) and Rural Telephone Finance Cooperative (“RTFC”) are VIEs that are required to be consolidated by CFC. NCSC is a taxable member-owned cooperative that may provide financing to members of CFC, government or quasi-government entities which own electric utility systems that meet the Rural Electrification Act definition of “rural,” and for-profit and nonprofit entities that are owned, operated or controlled by, or provide significant benefits to certain members of CFC. RTFC is a taxable Subchapter T cooperative association that provides financing for its rural telecommunications members and their affiliates. Unless stated otherwise, references to “we,” “our” or “us” relate to CFC and its consolidated entities. Restricted Cash Restricted cash, which consists primarily of member funds held in escrow for certain specifically designed cooperative programs, totaled $9 million and $8 million as of August 31, 2019 and May 31, 2019 , respectively. Assets Held for Sale On March 14, 2018, CFC entered into a purchase and sale agreement (“the agreement”), which was subsequently amended, for the sale of a parcel of land, consisting of approximately 28 acres, located in Loudoun County, Virginia. We designated the property, which had a carrying value of $14 million , as held for sale and reclassified it from fixed assets, net to other assets on our consolidated balance sheet. On July 22, 2019, we closed on the sale of the land and received net proceeds of $22 million , resulting in a gain of $8 million on the sale of this property, which is reported in other non-interest income (expense) on our condensed consolidated statements of operations. Interest Income The following table presents interest income, by interest-earning asset category, for the three months ended August 31, 2019 and 2018 . Three Months Ended August 31, (Dollars in thousands) 2019 2018 Interest income by interest-earning asset type: Long-term fixed-rate loans (1) $ 258,478 $ 251,801 Long-term variable-rate loans 9,756 9,381 Line of credit loans 16,033 11,633 TDR loans (2) 206 218 Other income, net (3) (284 ) (325 ) Total loans 284,189 272,708 Cash, time deposits and investment securities 5,826 5,783 Total interest income $ 290,015 $ 278,491 ____________________________ (1) Includes loan conversion fees, which are generally deferred and recognized as interest income using the effective interest method. (2) Troubled debt restructured (“TDR”) loans. (3) Consists of late payment fees, commitment fees and net amortization of deferred loan fees and loan origination costs. Deferred income of $56 million and $58 million as of August 31, 2019 and May 31, 2019 , respectively, consists primarily of deferred loan conversion fees totaling $50 million and $52 million , respectively. Deferred loan conversion fees are recognized in interest income using the effective interest method. Interest Expense The following table presents interest expense, by debt product type, for the three months ended August 31, 2019 and 2018 . Three Months Ended August 31, (Dollars in thousands) 2019 2018 Interest expense by debt product type: (1)(2) Short-term borrowings $ 22,822 $ 19,419 Medium-term notes 32,076 32,410 Collateral trust bonds 65,381 77,705 Guaranteed Underwriter Program notes payable 40,433 35,334 Farmer Mac notes payable 25,074 21,111 Other notes payable 254 322 Subordinated deferrable debt 12,882 9,417 Subordinated certificates 14,349 14,513 Total interest expense $ 213,271 $ 210,231 ____________________________ (1) Includes amortization of debt discounts and debt issuance costs, which are generally deferred and recognized as interest expense using the effective interest method. Issuance costs related to dealer commercial paper, however, are recognized as interest expense immediately as incurred. (2) Includes fees related to funding arrangements, such as up-front fees paid to banks participating in our committed bank revolving line of credit agreements. Depending on the nature of the fee, amounts may be deferred and recognized as interest expense ratably over the term of the arrangement or recognized immediately as incurred. Recent Accounting Changes and Other Developments Accounting Standards Adopted in Fiscal Year 2020 Derivatives and Hedging—Targeted Improvements to Accounting for Hedging Activities In August 2017, the FASB issued ASU 2017-12, Derivatives and Hedging—Targeted Improvements to Accounting for Hedging Acti vities, which expands the types of risk management strategies that qualify for hedge accounting treatment to more closely align the results of hedge accounting with the economics of certain risk management activities and simplifies certain hedge documentation and assessment requirement. It also eliminates the concept of separately recording hedge ineffectiveness and expands disclosure requirements. The guidance is effective for public entities for fiscal years beginning after December 15, 2018, including interim periods within those years. Early adoption is permitted in any interim period or fiscal year before the effective date. We adopted this guidance on June 1, 2019. Hedge accounting is elective, and we currently apply hedge accounting on a limited basis, specifically when we enter into treasury rate lock agreements. The adoption of this guidance did not have an impact on our consolidated financial statements or cash flows. If we continue to elect not to apply hedge accounting to our interest rate swaps, the guidance will not have an impact on our consolidated financial statements or cash flows. Receivables—Nonrefundable Fees and Other Cost In March 2017, the FASB issued ASU 2017-08, Receivables—Nonrefundable Fees and Other Costs, which shortens the amortization period for the premium on certain callable debt securities to the earliest call date rather the maturity date. The guidance is applicable to any individual debt security, purchased at a premium, with an explicit and noncontingent call feature with a fixed price on a preset date. The guidance does not impact the accounting for purchased callable debt securities held at a discount. The guidance is effective for public entities in fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. We adopted this guidance on June 1, 2019. The adoption of this guidance did not have a material impact on our consolidated financial statements or cash flows. Leases In February 2016, the FASB issued ASU 2016-02, Leases, which provides new guidance that is intended to improve financial reporting about leasing transactions. The new guidance requires the recognition of a right-of use asset and lease liability on the consolidated balance sheet by lessees for those leases classified as operating leases under previous guidance. It also requires new disclosures to help investors and other financial statement users better understand the amount, timing, and uncertainty of cash flows arising from leases. The guidance is effective for fiscal years and interim periods within those fiscal years beginning after December 15, 2018. We adopted this guidance on June 1, 2019. The adoption of this guidance did not have a material impact on our consolidated financial statements or cash flows. Accounting Standards Issued But Not Yet Adopted Fair Value Measurement—Changes to the Disclosure Requirements for Fair Value Measurement In August 2018, the FASB issued ASU 2018-13, Fair Value Measurement—Changes to the Disclosure Requirements for Fair Value Measurement, which eliminates, adds and modifies certain disclosure requirements for fair value measurements as part of its disclosure framework project. The guidance is effective for public entities for fiscal years beginning after December 15, 2019, including interim periods within those years. Early adoption is permitted in any interim period or fiscal year before the effective date. The guidance is effective for us beginning June 1, 2020. We do not expect that the adoption of this guidance will have a material impact on our consolidated financial statements or cash flows. Financial Instruments—Credit Losses: Measurement of Credit Losses on Financial Instruments In June 2016, the FASB issued ASU 2016-13, Financial Instruments—Credit Losses: Measurement of Credit Losses on Financial Instruments, which replaces the existing incurred credit loss model and establishes a single credit loss framework based on a current expected credit loss model for financial assets carried at amortized cost, including loans and held-to- maturity debt securities. The current expected loss model requires an entity to estimate credit losses expected over the life of the credit exposure upon initial recognition of that exposure when the financial asset is originated or acquired, which will generally result in earlier recognition of credit losses. The guidance also amends the other-than-temporary model for available-for-sale debt securities by requiring the use of an allowance, rather than directly reducing the carrying value of the security. The new guidance also requires expanded credit quality disclosures. The new guidance is effective for fiscal years and interim periods within those fiscal years, beginning after December 15, 2019. This guidance is effective for us on June 1, 2020. While early adoption is permitted, we do not expect to elect that option. We are continuing to evaluate the impact of the guidance on our consolidated financial statements, including assessing and evaluating assumptions and models to estimate losses. Upon adoption of the guidance on June 1, 2020, we will be required to record a cumulative effect adjustment to retained earnings for the impact as of the date of adoption. The impact will depend on our portfolio composition and credit quality at the date of adoption, as well as forecasts at that time.

Variable Interest Entities - (N

Variable Interest Entities - (Notes)	3 Months Ended
	Aug. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Variable Interest Entity Disclosure	NOTE 2—VARIABLE INTEREST ENTITIES NCSC and RTFC meet the definition of a VIE because they do not have sufficient equity investment at risk to finance their activities without financial support. CFC is the primary source of funding for NCSC and the sole source of funding for RTFC. Under the terms of management agreements with each company, CFC manages the business operations of NCSC and RTFC. CFC also unconditionally guarantees full indemnification for any loan losses of NCSC and RTFC pursuant to guarantee agreements with each company. CFC earns management and guarantee fees from its agreements with NCSC and RTFC. NCSC and RTFC creditors have no recourse against CFC in the event of a default by NCSC and RTFC, unless there is a guarantee agreement under which CFC has guaranteed NCSC or RTFC debt obligations to a third party. The following table provides information on incremental consolidated assets and liabilities of VIEs included in CFC’s condensed consolidated financial statements, after intercompany eliminations, as of August 31, 2019 and May 31, 2019 . (Dollars in thousands) August 31, 2019 May 31, 2019 Total loans outstanding $ 1,048,892 $ 1,087,988 Other assets 10,074 10,963 Total assets $ 1,058,966 $ 1,098,951 Long-term debt $ 6,000 $ 6,000 Other liabilities 36,878 33,385 Total liabilities $ 42,878 $ 39,385 The following table provides information on CFC’s credit commitments to NCSC and RTFC, and its potential exposure to loss as of August 31, 2019 and May 31, 2019 . (Dollars in thousands) August 31, 2019 May 31, 2019 CFC credit commitments $ 5,500,000 $ 5,500,000 Outstanding commitments: Borrowings payable to CFC (1) 1,019,103 1,059,629 Credit enhancements: CFC third-party guarantees 11,339 10,091 Other credit enhancements 16,171 14,251 Total credit enhancements (2) 27,510 24,342 Total outstanding commitments 1,046,613 1,083,971 CFC available credit commitments $ 4,453,387 $ 4,416,029 ____________________________ (1) Borrowings payable to CFC are eliminated in consolidation. (2) Excludes interest due on these instruments. CFC loans to NCSC and RTFC are secured by all assets and revenue of NCSC and RTFC. CFC’s maximum potential exposure, including interest due, for the credit enhancements totaled $29 million as of August 31, 2019 . The maturities for obligations guaranteed by CFC extend through 2031.

Investment Securities - (Notes)

Investment Securities - (Notes)	3 Months Ended
	Aug. 31, 2019
Investments [Abstract]
Investment Securities	NOTE 3—INVESTMENT SECURITIES We currently hold investments in equity and debt securities. We record purchases and sales of our investment securities on a trade-date basis. The accounting and measurement framework for investment securities differs depending on the security type and the classification. Equity Securities The following table presents the fair value of our equity securities, all of which had readily determinable fair values, as of August 31, 2019 and May 31, 2019 . (Dollars in thousands) August 31, 2019 May 31, 2019 Equity securities at fair value: Farmer Mac—Series A, B and C non-cumulative preferred stock $ 58,166 $ 82,445 Farmer Mac—class A common stock 5,756 5,088 Total equity securities at fair value $ 63,922 $ 87,533 We recognized net unrealized gains on our investments in equity securities of $2 million for the three months ended August 31, 2019 . We recognized net unrealized losses on our investments in equity securities of $1 million during the three months ended August 31, 2018 . These unrealized amounts are reported as a component of non-interest income on our condensed consolidated statements of operations. On June 12, 2019, Farmer Mac redeemed its Series B non-cumulative preferred stock at a redemption price of $25.00 per share, plus any declared and unpaid dividends through and including the redemption date. The amortized cost of our investment in the Farmer Mac Series B non-cumulative preferred stock was $25 million as of the redemption date, which equaled the per share redemption price. Debt Securities We currently classify and account for our investments in debt securities as held to maturity because we have the positive intent and ability to hold these securities to maturity. If we acquire debt securities that we may sell prior to maturity in response to changes in our investment strategy, liquidity needs, credit risk mitigating considerations, market risk profile or for other reasons, we would classify such securities as available for sale. We report debt securities classified as held to maturity on our condensed consolidated balance sheets at amortized cost. Interest income, including amortization of premiums and accretion of discounts, is generally recognized over the contractual life of the securities based on the effective yield method. Pursuant to our investment policy guidelines, all fixed-income debt securities, at the time of purchase, must be rated at least investment grade and on stable outlook based on external credit ratings from at least two of the leading global credit rating agencies, when available, or the corresponding equivalent, when not available. Securities rated investment grade, that is those rated Baa3 or higher by Moody’s Investors Service (“Moody’s”) or BBB- or higher by S&P or BBB- or higher by Fitch Ratings Inc. (“Fitch”), are generally considered by the rating agencies to be of lower credit risk than non-investment grade securities. Amortized Cost and Fair Value of Debt Securities The following tables present the amortized cost and fair value of our debt securities and the corresponding gross unrealized gains and losses, by classification category and major security type, as of August 31, 2019 and May 31, 2019 . August 31, 2019 (Dollars in thousands) Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value Debt securities held-to-maturity: Certificates of deposit $ 6,123 $ 2 $ — $ 6,125 Commercial paper 5,950 — — 5,950 U.S. agency debt securities 4,563 201 — 4,764 Corporate debt securities 481,914 9,426 (219 ) 491,121 Commercial MBS: Agency 7,243 473 — 7,716 Non-agency 3,453 — (5 ) 3,448 Total commercial MBS 10,696 473 (5 ) 11,164 U.S. state and municipality debt securities 9,606 520 — 10,126 Foreign government debt securities 1,257 58 — 1,315 Other ABS (1) 49,466 448 (3 ) 49,911 Total debt securities held-to-maturity $ 569,575 $ 11,128 $ (227 ) $ 580,476 May 31, 2019 (Dollars in thousands) Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value Debt securities held-to-maturity: Certificates of deposit $ 1,000 $ — $ — $ 1,000 Commercial paper 12,395 — — 12,395 U.S. agency debt securities 3,207 108 — 3,315 Corporate debt securities 478,578 4,989 (912 ) 482,655 Commercial MBS: Agency 7,255 291 — 7,546 Non-agency 3,453 — (7 ) 3,446 Total commercial MBS 10,708 291 (7 ) 10,992 U.S. state and municipality debt securities 9,608 352 — 9,960 Foreign government debt securities 1,254 42 — 1,296 Other ABS (1) 48,694 290 (48 ) 48,936 Total debt securities held-to-maturity $ 565,444 $ 6,072 $ (967 ) $ 570,549 ____________________________ (1) Consists primarily of securities backed by auto lease loans, equipment-backed loans, auto loans and credit card loans. Debt Securities in Gross Unrealized Loss Position An unrealized loss exists when the fair value of an individual security is less than its amortized cost basis. The following table presents the fair value and gross unrealized losses for debt securities in a gross loss position, aggregated by security type, and the length of time the securities have been in a continuous unrealized loss position as of August 31, 2019 and May 31, 2019 . The securities are segregated between investments that have been in a continuous unrealized loss position for less than 12 months and 12 months or more based on the point in time that the fair value declined below the amortized cost basis. August 31, 2019 Unrealized Loss Position Less than 12 Months Unrealized Loss Position 12 Months or Longer Total (Dollars in thousands) Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Debt securities held-to-maturity: Corporate debt securities $ 50,895 $ (75 ) $ 45,650 $ (144 ) $ 96,545 $ (219 ) Commercial MBS, non-agency 3,447 (5 ) — — 3,447 (5 ) Other ABS (1) — — 7,909 (3 ) 7,909 (3 ) Total debt securities held-to-maturity $ 54,342 $ (80 ) $ 53,559 $ (147 ) $ 107,901 $ (227 ) May 31, 2019 Unrealized Loss Position Less than 12 Months Unrealized Loss Position 12 Months or Longer Total (Dollars in thousands) Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Debt securities held-to-maturity: Commercial paper (2) $ 2,688 $ — $ — $ — $ 2,688 $ — Corporate debt securities 45,999 (198 ) 164,086 (714 ) 210,085 (912 ) Commercial MBS, non-agency 1,996 (4 ) 1,448 (3 ) 3,444 (7 ) Other ABS (1) 1,982 (4 ) 13,840 (44 ) 15,822 (48 ) Total debt securities held-to-maturity $ 52,665 $ (206 ) $ 179,374 $ (761 ) $ 232,039 $ (967 ) ____________________________ (1) Consists primarily of securities backed by auto lease loans, equipment-backed loans, auto loans and credit card loans. (2) Unrealized losses on the commercial paper investments are less than $1,000 . Other-Than-Temporary Impairment We conduct periodic reviews of all securities with unrealized losses to evaluate whether the impairment is other than temporary. The number of individual securities in an unrealized loss position was 84 as of August 31, 2019 . We have assessed each security with gross unrealized losses included in the above table for credit impairment. As part of that assessment, we concluded that the unrealized losses are driven by changes in market interest rates rather than by adverse changes in the credit quality of these securities. Based on our assessment, we expect to recover the entire amortized cost basis of these securities, as we do not intend to sell any of the securities and have concluded that it is more likely than not that we will not be required to sell prior to recovery of the amortized cost basis. Accordingly, we currently consider the impairment of these securities to be temporary. Contractual Maturity and Yield The following table presents, by major security type, the remaining contractual maturity based on amortized cost and fair value of our held-to-maturity investment securities as of August 31, 2019 and May 31, 2019 . Because borrowers may have the right to call or prepay certain obligations, the expected maturities of our investments may differ from the scheduled contractual maturities presented below. August 31, 2019 (Dollars in thousands) Due in 1 Year or Less Due > 1 Year through 5 Years Due > 5 Years through 10 Years Due >10 Years Total Amortized cost: Certificates of deposit $ 5,123 $ 1,000 $ — $ — $ 6,123 Commercial paper 5,950 — — — 5,950 U.S. agency debt securities — 2,682 1,881 — 4,563 Corporate debt securities 61,766 408,037 12,111 — 481,914 Commercial MBS: Agency — 2,078 5,165 — 7,243 Non-agency — — — 3,453 3,453 Total commercial MBS — 2,078 5,165 3,453 10,696 U.S. state and municipality debt securities — 9,606 — — 9,606 Foreign government debt securities — 1,257 — — 1,257 Other ABS (1) — 49,466 — — 49,466 Total $ 72,839 $ 474,126 $ 19,157 $ 3,453 $ 569,575 Fair value: Certificates of deposit $ 5,125 $ 1,000 $ — $ — $ 6,125 Commercial paper 5,950 — — — 5,950 U.S. agency debt securities — 2,811 1,953 — 4,764 Corporate debt securities 61,784 416,655 12,682 — 491,121 Commercial MBS: Agency — 2,210 5,506 — 7,716 Non-Agency — — — 3,448 3,448 Total commercial MBS — 2,210 5,506 3,448 11,164 U.S. state and municipality debt securities — 10,126 — — 10,126 Foreign government debt securities — 1,315 — — 1,315 Other ABS (1) — 49,911 — — 49,911 Total $ 72,859 $ 484,028 $ 20,141 $ 3,448 $ 580,476 Weighted average coupon (2) 2.32 % 3.03 % 3.00 % 3.02 % 2.94 % May 31, 2019 (Dollars in thousands) Due in 1 Year or Less Due > 1 Year through 5 Years Due > 5 Years through 10 Years Due >10 Years Total Amortized cost: Certificates of deposit $ — $ 1,000 $ — $ — $ 1,000 Commercial paper 12,395 — — — 12,395 U.S. agency debt securities — 2,678 529 — 3,207 Corporate debt securities 51,923 414,788 11,867 — 478,578 Commercial MBS: Agency — 310 6,945 — 7,255 Non-agency — — — 3,453 3,453 Total Commercial MBS — 310 6,945 3,453 10,708 U.S. state and municipality debt securities — 9,608 — — 9,608 Foreign government debt securities — 1,254 — — 1,254 Other ABS (1) 510 45,730 2,454 — 48,694 Total $ 64,828 $ 475,368 $ 21,795 $ 3,453 $ 565,444 Fair value: Certificates of deposit $ — $ 1,000 $ — $ — $ 1,000 Commercial paper 12,395 — — — 12,395 U.S. agency debt securities — 2,769 546 — 3,315 Corporate debt securities 51,818 418,606 12,231 — 482,655 Commercial MBS: Agency — 317 7,229 — 7,546 Non-agency — — — 3,446 3,446 Total commercial MBS — 317 7,229 3,446 10,992 U.S. state and municipality debt securities — 9,960 — — 9,960 Foreign government debt securities — 1,296 — — 1,296 Other ABS (1) 509 45,916 2,511 — 48,936 Total $ 64,722 $ 479,864 $ 22,517 $ 3,446 $ 570,549 Weighted average coupon (2) 2.08 % 3.10 % 3.07 % 3.26 % 2.98 % ____________________________ (1) Consists primarily of securities backed by auto lease loans, equipment-backed loans, auto loans and credit card loans. (2) Calculated based on the weighted average coupon rate, which excludes the impact of amortization of premium and accretion of discount. The average contractual maturity and weighted average coupon of our held-to-maturity investment securities was three years and 2.94% , respectively, as of August 31, 2019 . The average credit rating of these securities, based on the equivalent lowest credit rating by Moody’s, S&P and Fitch was A2, A and A, respectively, as of August 31, 2019 . Realized Gains and Losses We did not sell any of our debt securities during the three months ended August 31, 2019 , and therefore have not recorded any realized gains or losses. In connection with Farmer Mac’s early redemption of its Series B non-cumulative preferred stock, we recorded a realized loss on equity securities of $0.2 million for the three months ended August 31, 2019 .

Loans - (Notes)

Loans - (Notes)	3 Months Ended
	Aug. 31, 2019
Loans and Leases Receivable Disclosure [Abstract]
Loans	NOTE 4—LOANS Loans, which are classified as held for investment, are carried at the outstanding unpaid principal balance net of unamortized loan origination costs. The following table presents the outstanding principal balance of loans to members, including deferred loan origination costs, and unadvanced loan commitments by loan type and member class, as of August 31, 2019 and May 31, 2019 . August 31, 2019 May 31, 2019 (Dollars in thousands) Loans Outstanding Unadvanced Commitments (1) Loans Outstanding Unadvanced Commitments (1) Loan type: Long-term loans: Fixed rate $ 23,677,234 $ — $ 23,094,253 $ — Variable rate 962,541 5,140,530 1,066,880 5,448,636 Total long-term loans 24,639,775 5,140,530 24,161,133 5,448,636 Lines of credit 1,648,824 7,913,213 1,744,531 7,788,922 Total loans outstanding 26,288,599 13,053,743 25,905,664 13,237,558 Deferred loan origination costs 11,239 — 11,240 — Loans to members $ 26,299,838 $ 13,053,743 $ 25,916,904 $ 13,237,558 Member class: CFC: Distribution $ 20,484,460 $ 8,568,888 $ 20,155,266 $ 8,773,018 Power supply 4,671,035 3,456,266 4,578,841 3,466,680 Statewide and associate 84,212 168,564 83,569 165,687 Total CFC 25,239,707 12,193,718 24,817,676 12,405,385 NCSC 697,791 575,888 742,888 552,840 RTFC 351,101 284,137 345,100 279,333 Total loans outstanding 26,288,599 13,053,743 25,905,664 13,237,558 Deferred loan origination costs 11,239 — 11,240 — Loans to members $ 26,299,838 $ 13,053,743 $ 25,916,904 $ 13,237,558 ____________________________ (1) The interest rate on unadvanced loan commitments is not set until an advance is made; therefore, all long-term unadvanced loan commitments are reported as variable-rate. However, the borrower may select either a fixed or a variable rate when an advance on a commitment is made. Unadvanced Loan Commitments Unadvanced loan commitments represent approved and executed loan contracts for which funds have not been advanced to borrowers. The following table summarizes the available balance under unadvanced loan commitments as of August 31, 2019 and the related maturities by fiscal year and thereafter by loan type: Available Balance Notional Maturities of Unadvanced Loan Commitments (Dollars in thousands) 2020 2021 2022 2023 2024 Thereafter Line of credit loans $ 7,913,213 $ 609,206 $ 4,128,566 $ 485,285 $ 1,364,426 $ 1,055,813 $ 269,917 Long-term loans 5,140,530 306,460 665,361 1,295,466 1,080,699 1,634,791 157,753 Total $ 13,053,743 $ 915,666 $ 4,793,927 $ 1,780,751 $ 2,445,125 $ 2,690,604 $ 427,670 Unadvanced line of credit commitments accounted for 61% of total unadvanced loan commitments as of August 31, 2019 , while unadvanced long-term loan commitments accounted for 39% of total unadvanced loan commitments. Unadvanced line of credit commitments are typically revolving facilities for periods not to exceed five years. Unadvanced line of credit commitments generally serve as supplemental back-up liquidity to our borrowers. Historically, borrowers have not drawn the full commitment amount for line of credit facilities, and we have experienced a very low utilization rate on line of credit loan facilities regardless of whether or not we are obligated to fund the facility where a material adverse change exists. Our unadvanced long-term loan commitments have a five-year draw period under which a borrower may advance funds prior to the expiration of the commitment. We expect that the majority of the long-term unadvanced loan commitments of $5,141 million will be advanced prior to the expiration of the commitment. Because we historically have experienced a very low utilization rate on line of credit loan facilities, which account for the majority of our total unadvanced loan commitments, we believe the unadvanced loan commitment total of $13,054 million as of August 31, 2019 is not necessarily representative of our future funding cash requirements. Unadvanced Loan Commitments—Conditional The substantial majority of our line of credit commitments and all of our unadvanced long-term loan commitments include material adverse change clauses. Unadvanced loan commitments subject to material adverse change clauses totaled $10,050 million and $10,294 million as of August 31, 2019 and May 31, 2019 , respectively. Prior to making an advance on these facilities, we confirm that there has been no material adverse change in the business or condition, financial or otherwise, of the borrower since the time the loan was approved and confirm that the borrower is currently in compliance with loan terms and conditions. In some cases, the borrower’s access to the full amount of the facility is further constrained by the designated purpose, imposition of borrower-specific restrictions or by additional conditions that must be met prior to advancing funds. Unadvanced Loan Commitments—Unconditional Unadvanced loan commitments not subject to material adverse change clauses at the time of each advance consisted of unadvanced committed lines of credit totaling $3,004 million and $2,944 million as of August 31, 2019 and May 31, 2019 , respectively. As such, we are required to advance amounts on these committed facilities as long as the borrower is in compliance with the terms and conditions of the facility. The following table summarizes the available balance under unconditional committed lines of credit, and the related maturities by fiscal year and thereafter, as of August 31, 2019 . Available Balance Notional Maturities of Unconditional Committed Lines of Credit (Dollars in thousands) 2020 2021 2022 2023 2024 Thereafter Committed lines of credit $3,003,647 $260,886 $478,489 $171,875 $1,166,687 $811,510 $114,200 Loan Sales We transfer, from time to time, loans to third parties under our direct loan sale program. We sold CFC loans with outstanding balances totaling $20 million , at par for cash, during the three months ended August 31, 2019 . We did not have any loan sales during the three months ended August 31, 2018 . We recorded immaterial losses upon the sale of these loans, attributable to the unamortized deferred loan origination costs associated with the transferred loans. Pledging of Loans We are required to pledge eligible mortgage notes in an amount at least equal to the outstanding balance of our secured debt. The following table summarizes our loans outstanding as collateral pledged to secure our collateral trust bonds, Clean Renewable Energy Bonds, notes payable to Farmer Mac and notes payable under USDA’s Guaranteed Underwriter Program (“Guaranteed Underwriter Program”) and the amount of the corresponding debt outstanding as of August 31, 2019 and May 31, 2019 . See “Note 6—Short-Term Borrowings” and “Note 7—Long-Term Debt” for information on our borrowings. (Dollars in thousands) August 31, 2019 May 31, 2019 Collateral trust bonds: 2007 indenture: Distribution system mortgage notes $ 8,557,299 $ 8,775,231 RUS-guaranteed loans qualifying as permitted investments 133,129 134,678 Total pledged collateral $ 8,690,428 $ 8,909,909 Collateral trust bonds outstanding 7,622,711 7,622,711 1994 indenture: Distribution system mortgage notes $ 46,522 $ 47,331 Collateral trust bonds outstanding 40,000 40,000 Farmer Mac: Distribution and power supply system mortgage notes $ 3,760,219 $ 3,751,798 Notes payable outstanding 2,962,478 3,054,914 Clean Renewable Energy Bonds Series 2009A: Distribution and power supply system mortgage notes $ 9,799 $ 10,349 Cash 802 415 Total pledged collateral $ 10,601 $ 10,764 Notes payable outstanding 9,225 9,225 Federal Financing Bank: Distribution and power supply system mortgage notes $ 6,127,684 $ 6,157,218 Notes payable outstanding 5,387,155 5,410,507 Credit Concentration Concentrations may exist when there are amounts loaned to borrowers engaged in similar activities or in geographic areas that would cause them to be similarly impacted by economic or other conditions or when there are large exposures to single borrowers. As a tax-exempt, member-owned finance cooperative, CFC’s principal focus is to provide funding to its rural electric utility cooperative members to assist them in acquiring, constructing and operating electric distribution systems, power supply systems and related facilities. We serve electric and telecommunications members throughout the United States, with a total of 900 borrowers located in 49 states as of August 31, 2019 . Loans to borrowers in Texas accounted for approximately 16% and 15% of total loans outstanding as of August 31, 2019 and May 31, 2019 , respectively, representing the largest concentration of outstanding loans to borrowers and the largest number of borrowers in any one state. Because we lend primarily to our rural electric utility cooperative members, we have a loan portfolio subject to single-industry and single-obligor concentration risks. Loans outstanding to electric utility organizations represented approximately 99% of total loans outstanding as of August 31, 2019 , unchanged from May 31, 2019 . The remaining loans outstanding in our portfolio were to RTFC members, affiliates and associates in the telecommunications industry. The outstanding loan exposure for our 20 largest borrowers was 22% as of both August 31, 2019 and May 31, 2019 . The 20 largest borrowers consisted of 10 distribution systems, nine power supply systems and one NCSC associate as of both August 31, 2019 and May 31, 2019 . The largest total outstanding exposure to a single borrower or controlled group represented approximately 2% of total loans outstanding as of both August 31, 2019 and May 31, 2019 . As part of our strategy in managing our credit exposure, we entered into a long-term standby purchase commitment agreement with Farmer Mac during fiscal year 2016. Under this agreement, we may designate certain long-term loans to be covered under the commitment, subject to approval by Farmer Mac, and in the event any such loan later goes into payment default for at least 90 days, upon request by us, Farmer Mac must purchase such loan at par value. The aggregate unpaid principal balance of designated and Farmer Mac approved loans was $602 million and $619 million as of August 31, 2019 and May 31, 2019 , respectively. Under the agreement, we are required to pay Farmer Mac a monthly fee based on the unpaid principal balance of loans covered under the purchase commitment. No loans had been put to Farmer Mac for purchase, pursuant to this agreement, as of August 31, 2019 . Also, we had long-term loans totaling $152 million and $154 million as of August 31, 2019 and May 31, 2019 , respectively, guaranteed by RUS. Credit Quality Assessing the overall credit quality of our loan portfolio and measuring our credit risk is an ongoing process that involves tracking payment status, charge-offs, troubled debt restructurings, nonperforming and impaired loans, the internal risk ratings of our borrowers and other indicators of credit risk. We monitor and subject each borrower and loan facility in our loan portfolio to an individual risk assessment based on quantitative and qualitative factors. Internal risk ratings and payment status trends are indicators, among others, of the probability of borrower default and level of credit risk in our loan portfolio. Borrower Risk Ratings As part of our credit risk management process, we monitor and evaluate each borrower and loan in our loan portfolio and assign internal borrower and loan facility risk ratings based on quantitative and qualitative assessments. Our borrower risk ratings are intended to assess probability of default. Each risk rating is reassessed annually following the receipt of the borrower’s audited financial statements; however, interim risk-rating downgrades or upgrades may occur as a result of significant developments or trends. Our borrower risk ratings are intended to align with banking regulatory agency credit risk rating definitions of pass and criticized classifications, with criticized divided between special mention, substandard and doubtful. Pass ratings reflect relatively low probability of default, while criticized ratings have a higher probability of default. Following is a description of each rating category. • Pass : Borrowers that are not experiencing difficulty and/or not showing a potential or well-defined credit weakness. • Special Mention : Borrowers that may be characterized by a potential credit weakness or deteriorating financial condition that is not sufficiently serious to warrant a classification of substandard or doubtful. • Substandard : Borrowers that display a well-defined credit weakness that may jeopardize the full collection of principal and interest. • Doubtful : Borrowers that have a well-defined credit weakness or weaknesses that make full collection of principal and interest, on the basis of currently known facts, conditions and collateral values, highly questionable and improbable. Loans to borrowers in the pass, special mention and substandard categories are generally considered not to be individually impaired and are included in the loan pools for determining the collective reserve component of the allowance for loan losses. Loans to borrowers in the doubtful category are considered to be impaired and are therefore individually assessed for impairment in determining the specific reserve component of the allowance for loan losses. The following tables present total loans outstanding, by member class and borrower risk rating category, based on the risk ratings used in the estimation of our allowance for loan losses as of August 31, 2019 and May 31, 2019 . For purposes of these tables and for determining the allowance for loan losses, loans to borrowers that are supported by a full guarantee of repayment by the parent company are grouped in the same risk rating category of the guarantor parent company, rather than the risk rating category of the subsidiary borrower. August 31, 2019 (Dollars in thousands) Pass Special Mention Substandard Doubtful Total CFC: Distribution $ 20,354,654 $ 8,222 $ 121,584 $ — $ 20,484,460 Power supply 4,623,131 — 47,904 — 4,671,035 Statewide and associate 69,212 15,000 — — 84,212 CFC total 25,046,997 23,222 169,488 — 25,239,707 NCSC 697,791 — — — 697,791 RTFC 345,634 — 5,467 — 351,101 Total loans outstanding $ 26,090,422 $ 23,222 $ 174,955 $ — $ 26,288,599 May 31, 2019 (Dollars in thousands) Pass Special Mention Substandard Doubtful Total CFC: Distribution $ 20,022,193 $ 10,375 $ 122,698 $ — $ 20,155,266 Power supply 4,530,708 — 48,133 — 4,578,841 Statewide and associate 68,569 15,000 — — 83,569 CFC total 24,621,470 25,375 170,831 — 24,817,676 NCSC 742,888 — — — 742,888 RTFC 339,508 — 5,592 — 345,100 Total loans outstanding $ 25,703,866 $ 25,375 $ 176,423 $ — $ 25,905,664 The substantial majority of the loans in the substandard category are attributable to loans to one electric distribution cooperative borrower and its subsidiary totaling $169 million and $171 million as of August 31, 2019 and May 31, 2019 , respectively. The electric distribution cooperative owns and operates a distribution and transmission system. Several years ago, it established a subsidiary to deploy retail broadband service in underserved rural communities. Although the borrower has experienced financial difficulties due to recent net losses and liquidity constraints, the borrower and its subsidiary are current with regard to all principal and interest payments and have never been delinquent. The borrower, which operates in a territory that is not rate-regulated, recently increased its electric and broadband rates and has begun taking other actions to improve its financial performance and liquidity. All of the loans outstanding to this borrower were secured under our typical collateral requirements for long-term loan advances as of August 31, 2019 . We currently expect to collect all principal and interest amounts due from the borrower and its subsidiary. Accordingly, the loans outstanding to this borrower and its subsidiary were not deemed to be impaired as of August 31, 2019 . Payment Status of Loans The following tables present the payment status of loans outstanding by member class as of August 31, 2019 and May 31, 2019 . As indicated in the table, we did not have any past due loans as of either August 31, 2019 or May 31, 2019 . August 31, 2019 (Dollars in thousands) Current 30-89 Days Past Due 90 Days or More Past Due (1) Total Past Due Total Loans Outstanding Nonaccrual Loans CFC: Distribution $ 20,484,460 $ — $ — $ — $ 20,484,460 $ — Power supply 4,671,035 — — — 4,671,035 — Statewide and associate 84,212 — — — 84,212 — CFC total 25,239,707 — — — 25,239,707 — NCSC 697,791 — — — 697,791 — RTFC 351,101 — — — 351,101 — Total loans outstanding $ 26,288,599 $ — $ — $ — $ 26,288,599 $ — Percentage of total loans 100.00 % — % — % — % 100.00 % — % May 31, 2019 (Dollars in thousands) Current 30-89 Days Past Due 90 Days or More Past Due (1) Total Total Loans Outstanding Nonaccrual Loans CFC: Distribution $ 20,155,266 $ — $ — $ — $ 20,155,266 $ — Power supply 4,578,841 — — — 4,578,841 — Statewide and associate 83,569 — — — 83,569 — CFC total 24,817,676 — — — 24,817,676 — NCSC 742,888 — — — 742,888 — RTFC 345,100 — — — 345,100 — Total loans outstanding $ 25,905,664 $ — $ — $ — $ 25,905,664 $ — Percentage of total loans 100.00 % — % — % — % 100.00 % — % ____________________________ (1) All loans 90 days or more past due are on nonaccrual status. Troubled Debt Restructurings We did not have any loans modified as TDRs during the three months ended August 31, 2019 . The following table provides a summary of loans modified as TDRs in prior periods, the performance status of these loans and the unadvanced loan commitments related to the TDR loans, by member class, as of August 31, 2019 and May 31, 2019 . August 31, 2019 May 31, 2019 (Dollars in thousands) Loans Outstanding % of Total Loans Unadvanced Commitments Loans Outstanding % of Total Loans Unadvanced Commitments TDR loans: Performing TDR loans: CFC/Distribution $ 5,755 0.02 % $ — $ 6,261 0.03 % $ — RTFC 5,467 0.02 — 5,592 0.02 — Total performing TDR loans 11,222 0.04 — 11,853 0.05 — Total TDR loans $ 11,222 0.04 % $ — $ 11,853 0.05 % $ — We did not have any TDR loans classified as nonperforming as of August 31, 2019 or May 31, 2019 . TDR loans classified as performing as of August 31, 2019 and May 31, 2019 were performing in accordance with the terms of their respective restructured loan agreement and on accrual status as of the respective reported dates. One borrower with a TDR loan also had two line of credit facilities as of both August 31, 2019 and May 31, 2019 . One line of credit facility for $6 million as of both August 31, 2019 and May 31, 2019 , is restricted for fuel purchases only. Outstanding loans under this facility totaled $1 million and $3 million as of August 31, 2019 and May 31, 2019 , respectively, and were classified as performing as of each respective date. The other line of credit facility for $2 million as of both August 31, 2019 and May 31, 2019 , provides bridge funding for electric work plan expenditures in anticipation of receiving RUS funding. Outstanding loans under this facility totaled $1 million as of both August 31, 2019 and May 31, 2019 , respectively, and were classified as performing. Nonperforming Loans In addition to TDR loans that may be classified as nonperforming, we also may have nonperforming loans that have not been modified as a TDR. We did not have any loans classified as nonperforming as of either August 31, 2019 or May 31, 2019 . We had no foregone interest income for loans on nonaccrual status during the three months ended August 31, 2019 and 2018 . Impaired Loans The following table provides information on loans classified as individually impaired as of August 31, 2019 and May 31, 2019 . August 31, 2019 May 31, 2019 (Dollars in thousands) Recorded Investment Related Allowance Recorded Investment Related Allowance With no specific allowance recorded: CFC $ 5,755 $ — $ 6,261 $ — With a specific allowance recorded: RTFC 5,467 989 5,592 1,021 Total impaired loans $ 11,222 $ 989 $ 11,853 $ 1,021 The following table presents, by company, the average recorded investment for individually impaired loans and the interest income recognized on these loans for the three months ended August 31, 2019 and 2018 . Three Months Ended August 31, 2019 2018 2019 2018 (Dollars in thousands) Average Recorded Investment Interest Income Recognized CFC $ 6,239 $ 6,504 $ 137 $ 142 RTFC 5,547 6,048 69 76 Total impaired loans $ 11,786 $ 12,552 $ 206 $ 218 Net Charge-Offs Charge-offs represent the amount of a loan that has been removed from our consolidated balance sheet when the loan is deemed uncollectible. Generally the amount of a charge-off is the recorded investment in excess of the fair value of the expected cash flows from the loan, or, if the loan is collateral dependent, the fair value of the underlying collateral securing the loan. We report charge-offs net of amounts recovered on previously charged off loans. We had no loan defaults or charge-offs during the three months ended August 31, 2019 and 2018 .

Allowance for Loan Losses - (No

Allowance for Loan Losses - (Notes)	3 Months Ended
	Aug. 31, 2019
Loans and Leases Receivable Disclosure [Abstract]
Allowance for Loan Losses	NOTE 5—ALLOWANCE FOR LOAN LOSSES We maintain an allowance for loan losses that represents management’s estimate of probable losses inherent in our loan portfolio as of each balance sheet date. Our allowance for loan losses consists of a collective allowance for loans in our portfolio that are not individually impaired and a specific allowance for loans identified as individually impaired. The allowance for loan losses is reported separately on the consolidated balance sheet, and the provision for loan losses is separately reported on our condensed consolidated statements of operations. The following tables summarize changes, by company, in the allowance for loan losses as of and for the three months ended August 31, 2019 and 2018 . Three Months Ended August 31, 2019 (Dollars in thousands) CFC NCSC RTFC Total Balance as of May 31, 2019 $ 13,120 $ 2,007 $ 2,408 $ 17,535 Provision (benefit) for loan losses (158 ) 70 118 30 Balance as of August 31, 2019 $ 12,962 $ 2,077 $ 2,526 $ 17,565 Three Months Ended August 31, 2018 (Dollars in thousands) CFC NCSC RTFC Total Balance as of May 31, 2018 $ 12,300 $ 2,082 $ 4,419 $ 18,801 Provision (benefit) for loan losses 208 (70 ) (247 ) (109 ) Balance as of August 31, 2018 $ 12,508 $ 2,012 $ 4,172 $ 18,692 The following tables present, by company, the components of our allowance for loan losses and the recorded investment of the related loans as of August 31, 2019 and May 31, 2019 . August 31, 2019 (Dollars in thousands) CFC NCSC RTFC Total Ending balance of the allowance: Collective allowance $ 12,962 $ 2,077 $ 1,537 $ 16,576 Specific allowance — — 989 989 Total ending balance of the allowance $ 12,962 $ 2,077 $ 2,526 $ 17,565 Recorded investment in loans: Collectively evaluated loans $ 25,233,952 $ 697,791 $ 345,634 $ 26,277,377 Individually evaluated loans 5,755 — 5,467 11,222 Total recorded investment in loans $ 25,239,707 $ 697,791 $ 351,101 $ 26,288,599 Total recorded investment in loans, net (1) $ 25,226,745 $ 695,714 $ 348,575 $ 26,271,034 Allowance coverage ratio: Allowance as a percentage of total recorded investment in loans 0.05 % 0.30 % 0.72 % 0.07 % May 31, 2019 (Dollars in thousands) CFC NCSC RTFC Total Ending balance of the allowance: Collective allowance $ 13,120 $ 2,007 $ 1,387 $ 16,514 Specific allowance — — 1,021 1,021 Total ending balance of the allowance $ 13,120 $ 2,007 $ 2,408 $ 17,535 Recorded investment in loans: Collectively evaluated loans $ 24,811,415 $ 742,888 $ 339,508 $ 25,893,811 Individually evaluated loans 6,261 — 5,592 11,853 Total recorded investment in loans $ 24,817,676 $ 742,888 $ 345,100 $ 25,905,664 Total recorded investment in loans, net (1) $ 24,804,556 $ 740,881 $ 342,692 $ 25,888,129 Allowance coverage ratio: Allowance as a percentage of total recorded investment in loans 0.05 % 0.27 % 0.70 % 0.07 % ____________________________ (1) Excludes unamortized deferred loan origination costs of $11 million as of both August 31, 2019 and May 31, 2019 . As noted above in “Note 4-Loans,” we did not have any loans classified as nonperforming as of either August 31, 2019 or May 31, 2019 . In addition to the allowance for loan losses, we also maintain a reserve for unadvanced loan commitments at a level estimated by management to provide for probable losses under these commitments as of each balance sheet date, which was less than $1 million as of both August 31, 2019 and May 31, 2019 .

Short-Term Borrowings - (Notes)

Short-Term Borrowings - (Notes)	3 Months Ended
	Aug. 31, 2019
Debt Disclosure [Abstract]
Short-Term Debt	NOTE 6—SHORT-TERM BORROWINGS Short-term borrowings consist of borrowings with an original contractual maturity of one year or less and do not include the current portion of long-term debt. Our short-term borrowings totaled $4,028 million and accounted for 16% of total debt outstanding as of August 31, 2019 , compared with $3,608 million , or 14% , of total debt outstanding as of May 31, 2019 . The following table provides comparative information on our short-term borrowings as of August 31, 2019 and May 31, 2019 . (Dollars in thousands) August 31, 2019 May 31, 2019 Short-term borrowings: Commercial paper: Commercial paper sold through dealers, net of discounts $ 829,763 $ 944,616 Commercial paper sold directly to members, at par 1,240,830 1,111,795 Total commercial paper 2,070,593 2,056,411 Select notes to members 1,277,927 1,023,952 Daily liquidity fund notes to members 435,070 298,817 Medium-term notes to members 244,055 228,546 Total short-term borrowings $ 4,027,645 $ 3,607,726 Committed Bank Revolving Line of Credit Agreements We had $2,975 million of commitments under committed bank revolving line of credit agreements as of both August 31, 2019 and May 31, 2019 , respectively. Under our current committed bank revolving line of credit agreements, we have the ability to request up to $300 million of letters of credit, which would result in a reduction in the remaining available amount under the facilities. The following table presents the total commitment, the net amount available for use and the outstanding letters of credit under our committed bank revolving line of credit agreements as of August 31, 2019 and May 31, 2019 . August 31, 2019 May 31, 2019 (Dollars in millions) Total Commitment Letters of Credit Outstanding Net Available for Use Total Commitment Letters of Credit Outstanding Net Available for Use Maturity Annual Facility Fee (1) 3-year agreement $ 1,440 $ — $ 1,440 $ 1,440 $ — $ 1,440 November 28, 2021 7.5 bps 5-year agreement 1,535 3 1,532 1,535 3 1,532 November 28, 2023 10 bps Total $ 2,975 $ 3 $ 2,972 $ 2,975 $ 3 $ 2,972 ____________________________ (1) Facility fee determined by CFC’s senior unsecured credit ratings based on the pricing schedules put in place at the inception of the related agreement. We had no borrowings outstanding under our committed bank revolving line of credit agreements as of August 31, 2019 or May 31, 2019 , and we were in compliance with all covenants and conditions under the agreements as of each date.

Long-Term Debt - (Notes)

Long-Term Debt - (Notes)	3 Months Ended
	Aug. 31, 2019
Debt Instruments [Abstract]
Long-Term Debt	NOTE 7—LONG-TERM DEBT The following table displays long-term debt outstanding, by debt type, as of August 31, 2019 and May 31, 2019 . (Dollars in thousands) August 31, 2019 May 31, 2019 Secured long-term debt: Collateral trust bonds $ 7,662,711 $ 7,662,711 Unamortized discount (242,123 ) (244,643 ) Debt issuance costs (32,952 ) (34,336 ) Total collateral trust bonds 7,387,636 7,383,732 Guaranteed Underwriter Program notes payable 5,387,155 5,410,507 Farmer Mac notes payable 2,962,478 3,054,914 Other secured notes payable 9,225 9,225 Debt issuance costs (162 ) (178 ) Total other secured notes payable 9,063 9,047 Total secured notes payable 8,358,696 8,474,468 Total secured long-term debt 15,746,332 15,858,200 Unsecured long-term debt: Medium-term notes sold through dealers 2,935,540 2,962,375 Medium-term notes sold to members 418,208 397,080 Subtotal medium-term notes 3,353,748 3,359,455 Unamortized discount (848 ) (931 ) Debt issuance costs (18,492 ) (19,399 ) Total unsecured medium-term notes 3,334,408 3,339,125 Unsecured notes payable 13,701 13,701 Unamortized discount (164 ) (187 ) Debt issuance costs (41 ) (46 ) Total unsecured notes payable 13,496 13,468 Total unsecured long-term debt 3,347,904 3,352,593 Total long-term debt $ 19,094,236 $ 19,210,793 Collateral Trust Bonds Collateral trust bonds represent secured obligations sold to investors in the capital markets. Collateral trust bonds are secured by the pledge of mortgage notes or eligible securities in an amount at least equal to the principal balance of the bonds outstanding. On September 13, 2019, we provided notice to investors that we will redeem all $300 million outstanding principal amount of our 2.30% collateral trust bonds due November 15, 2019 on October 15, 2019. Secured Notes Payable We had outstanding secured notes payable totaling $5,387 million and $5,411 million as of August 31, 2019 and May 31, 2019 , respectively, under bond purchase agreements with the Federal Financing Bank and a bond guarantee agreement with RUS issued under the Guaranteed Underwriter Program, which provides guarantees to the Federal Financing Bank. We pay RUS a fee of 30 basis points per year on the total amount outstanding. We had up to $1,350 million available for access under the Guaranteed Underwriter Program as of August 31, 2019 . The notes outstanding under the Guaranteed Underwriter Program contain a provision that if during any portion of the fiscal year, our senior secured credit ratings do not have at least two of the following ratings: (i) A3 or higher from Moody’s, (ii) A- or higher from S&P, (iii) A- or higher from Fitch, or (iv) an equivalent rating from a successor rating agency to any of the above rating agencies, we may not make cash patronage capital distributions in excess of 5% of total patronage capital. We are required to pledge eligible distribution system or power supply system loans as collateral in an amount at least equal to the total principal amount of notes outstanding under the Guaranteed Underwriter Program. See “Note 4—Loans” for additional information on the collateral pledged to secure notes payable under this program. We have two revolving note purchase agreements with Farmer Mac, which together allow us to borrow up to $5,500 million from Farmer Mac. Under our first revolving note purchase agreement with Farmer Mac, dated March 24, 2011, as amended, we can currently borrow, subject to market conditions, up to $5,200 million at any time through January 11, 2022, and such date shall automatically extend on each anniversary date of the closing for an additional year, unless prior to any such anniversary date, Farmer Mac provides us with a notice that the draw period will not be extended beyond the remaining term. This revolving note purchase agreement allows us to borrow, repay and re-borrow funds at any time through maturity, as market conditions permit, provided that the outstanding principal amount at any time does not exceed the total available under the agreement. Each borrowing under the revolving note purchase agreement is evidenced by a pricing agreement setting forth the interest rate, maturity date and other related terms as we may negotiate with Farmer Mac at the time of each such borrowing. We may select a fixed rate or variable rate at the time of each advance with a maturity as determined in the applicable pricing agreement. Under this note purchase agreement with Farmer Mac, we had outstanding secured notes payable totaling $2,962 million and $3,055 million as of August 31, 2019 and May 31, 2019 , respectively. Under our second revolving note purchase agreement with Farmer Mac, dated July 31, 2015, as amended, we can borrow up to $300 million at any time through December 20, 2023 at a fixed spread over London Interbank Offered Rate (“LIBOR”). This agreement also allows us to borrow, repay and re-borrow funds at any time through maturity, provided that the outstanding principal amount at any time does not exceed the total available under the agreement. Prior to the maturity date, Farmer Mac may terminate the agreement upon 30 days written notice to us on periodic facility renewal dates, the first of which was January 31, 2019. Subsequent facility renewal dates are on each June 20 or December 20 thereafter until the maturity date. We may terminate the agreement upon 30 days written notice at any time. We did not have any outstanding notes payable under this revolving note purchase agreement with Farmer Mac as of August 31, 2019 and May 31, 2019 . Under the terms of the first revolving note purchase agreement with Farmer Mac described above, the $5,200 million commitment will increase to $5,500 million in the event the second revolving note purchase agreement is terminated. We are required to pledge eligible distribution system or power supply system loans as collateral in an amount at least equal to the total principal amount of notes outstanding under each of our Farmer Mac revolving note purchase agreements. See “Note 4—Loans” for additional information on the collateral pledged to secure notes payable under these programs. We were in compliance with all covenants and conditions under our senior debt indentures as of August 31, 2019 and May 31, 2019 .

Subordinated Deferrable Debt -

Subordinated Deferrable Debt - (Notes)	3 Months Ended
	Aug. 31, 2019
Subordinated Debt [Abstract]
Subordinated Deferrable Debt	NOTE 8—SUBORDINATED DEFERRABLE DEBT The following table presents subordinated deferrable debt outstanding as of August 31, 2019 and May 31, 2019 . See “Note 8—Subordinated Deferrable Debt” of our 2019 Form 10-K for additional information on the terms of our subordinated deferrable debt outstanding. (Dollars in thousands) August 31, 2019 May 31, 2019 4.75% due 2043 with a call date of April 30, 2023 $ 400,000 $ 400,000 5.25% due 2046 with a call date of April 20, 2026 350,000 350,000 5.50% due 2064 with a call date of May 15, 2024 250,000 250,000 Debt issuance costs (14,019 ) (13,980 ) Total subordinated deferrable debt $ 985,981 $ 986,020

Derivative Instruments and Hedg

Derivative Instruments and Hedging Activities - (Notes)	3 Months Ended
	Aug. 31, 2019
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Financial Instruments	NOTE 9—DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES We are an end user of derivative financial instruments and do not engage in derivative trading. We use derivatives, primarily interest rate swaps and Treasury rate locks, to manage interest rate risk. Derivatives may be privately negotiated contracts, which are often referred to as OTC derivatives, or they may be listed and traded on an exchange. We generally engage in OTC derivative transactions. Accounting for Derivatives In accordance with the accounting standards for derivatives and hedging activities, we record derivative instruments at fair value as either a derivative asset or derivative liability on our condensed consolidated balance sheets. We report derivative asset and liability amounts on a gross basis based on individual contracts, which does not take into consideration the effects of master netting agreements or collateral netting. Our derivatives transactions are not collateralized and do not include collateralization agreements with counterparties. Derivatives in a gain position are reported as derivative assets on our condensed consolidated balance sheets, while derivatives in a loss position are reported as derivative liabilities. Accrued interest related to derivatives is reported on our condensed consolidated balance sheets as a component of either accrued interest receivable or accrued interest payable. If we do not elect hedge accounting treatment, changes in the fair value of derivative instruments, which consist of net accrued periodic derivative cash settlements expense and derivative forward value amounts, are recognized in our condensed consolidated statements of operations under derivative gains (losses). If we elect hedge accounting treatment for derivatives, we formally document, designate and assess the effectiveness of the hedge relationship. Changes in the fair value of derivatives designated as qualifying fair value hedges are recognized in the same line item on our condensed consolidated statements of operations as the earnings effect of the related hedged item. Changes in the fair value of derivatives designated as qualifying cash flow hedges are recorded as a component of AOCI. Those amounts are reclassified into earnings in the same period during which the forecasted transaction impacts earnings and presented in the same line item on our condensed consolidated statements of operations as the earnings effect of the related hedged item. We generally do not designate interest rate swaps, which represented all of our outstanding derivatives as of August 31, 2019 , for hedge accounting. Accordingly, changes in the fair value of interest rate swaps are reported in our condensed consolidated statements of operations under derivative gains (losses). Net periodic cash settlements expense related to interest rate swaps are classified as an operating activity in our consolidated statements of cash flows. Outstanding Notional Amount of Derivatives Not Designated as Accounting Hedges The notional amount provides an indication of the volume of our derivatives activity, but this amount is not recorded on our condensed consolidated balance sheets. The notional amount is used only as the basis on which interest payments are determined and is not the amount exchanged. The following table shows the outstanding notional amounts and the weighted-average rate paid and received for our interest rate swaps, by type, as of August 31, 2019 and May 31, 2019 . The substantial majority of our interest rate swaps use an index based on LIBOR for either the pay or receive leg of the swap agreement. August 31, 2019 May 31, 2019 (Dollars in thousands) Notional Amount Weighted- Average Rate Paid Weighted- Average Rate Received Notional Weighted- Weighted- Pay-fixed swaps $ 7,319,015 2.84 % 2.27 % $ 7,379,280 2.83 % 2.60 % Receive-fixed swaps 3,399,000 2.96 2.56 3,399,000 3.25 2.56 Total interest rate swaps 10,718,015 2.88 2.36 10,778,280 2.97 2.58 Forward pay-fixed swaps 65,000 65,000 Total $ 10,783,015 $ 10,843,280 Impact of Derivatives on Condensed Consolidated Balance Sheets The following table displays the fair value of the derivative assets and derivative liabilities recorded on our condensed consolidated balance sheets and the related outstanding notional amount of our interest rate swaps by derivatives type, as of August 31, 2019 and May 31, 2019 . August 31, 2019 May 31, 2019 (Dollars in thousands) Fair Value Notional Balance Fair Value Notional Balance Derivative assets: Interest rate swaps $ 85,533 $ 2,641,803 $ 41,179 $ 2,332,104 Derivative liabilities: Interest rate swaps $ 820,872 $ 8,141,212 $ 391,724 $ 8,511,176 All of our master swap agreements include netting provisions that allow for offsetting of all contracts with a given counterparty in the event of default by one of the two parties. However, as indicated above, we report derivative asset and liability amounts on a gross basis by individual contracts. The following table presents the gross fair value of derivative assets and liabilities reported on our condensed consolidated balance sheets as of August 31, 2019 and May 31, 2019 , and provides information on the impact of netting provisions and collateral pledged, if any. August 31, 2019 Gross Amount of Recognized Assets/ Liabilities Gross Amount Offset in the Balance Sheet Net Amount of Assets/ Liabilities Presented in the Balance Sheet Gross Amount Not Offset in the Balance Sheet (Dollars in thousands) Financial Instruments Cash Collateral Pledged Net Amount Derivative assets: Interest rate swaps $ 85,533 $ — $ 85,533 $ 85,533 $ — $ — Derivative liabilities: Interest rate swaps 820,872 — 820,872 85,533 — 735,339 May 31, 2019 Gross Amount of Recognized Assets/ Liabilities Gross Amount Offset in the Balance Sheet Net Amount of Assets/ Liabilities Presented in the Balance Sheet Gross Amount Not Offset in the Balance Sheet (Dollars in thousands) Financial Instruments Cash Collateral Pledged Net Amount Derivative assets: Interest rate swaps $ 41,179 $ — $ 41,179 $ 41,176 $ — $ 3 Derivative liabilities: Interest rate swaps 391,724 — 391,724 41,176 — 350,548 Impact of Derivatives on Condensed Consolidated Statements of Operations Derivative gains (losses) reported in our condensed consolidated statements of operations consist of derivative cash settlements expense and derivative forward value gains (losses). Derivative cash settlements expense represents net contractual interest expense accruals on interest rate swaps during the period. The derivative forward value gains (losses) represent the change in fair value of our interest rate swaps during the reporting period due to changes in the estimate of future interest rates over the remaining life of our derivative contracts. The following table presents the components of the derivative gains (losses) reported in our condensed consolidated statements of operations for our interest rate swaps for three months ended August 31, 2019 and 2018 . Three Months Ended August 31, (Dollars in thousands) 2019 2018 Derivative gains (losses) attributable to: Derivative cash settlements expense $ (11,043 ) $ (12,829 ) Derivative forward value gains (losses) (384,682 ) 20,012 Derivative gains (losses) $ (395,725 ) $ 7,183 Credit Risk-Related Contingent Features Our derivative contracts typically contain mutual early-termination provisions, generally in the form of a credit rating trigger. Under the mutual credit rating trigger provisions, either counterparty may, but is not obligated to, terminate and settle the agreement if the credit rating of the other counterparty falls below a level specified in the agreement. If a derivative contract is terminated, the amount to be received or paid by us would be equal to the prevailing fair value, as defined in the agreement, as of the termination date. Our senior unsecured credit ratings from Moody’s and S&P were A2 and A, respectively, as of August 31, 2019 . Both Moody’s and S&P had our ratings on stable outlook as of August 31, 2019 . The following table displays the notional amounts of our derivative contracts with rating triggers as of August 31, 2019 , and the payments that would be required if the contracts were terminated as of that date because of a downgrade of our unsecured credit ratings or the counterparty’s unsecured credit ratings below A3/A-, below Baa1/BBB+, to or below Baa2/BBB, below Baa3/BBB-, or to or below Ba2/BB+ by Moody’s or S&P, respectively. In calculating the payment amounts that would be required upon termination of the derivative contracts, we assumed that the amounts for each counterparty would be netted in accordance with the provisions of the master netting agreements for each counterparty. The net payment amounts are based on the fair value of the underlying derivative instrument, excluding the credit risk valuation adjustment, plus any unpaid accrued interest amounts. (Dollars in thousands) Notional Amount Payable Due from CFC Receivable Due to CFC Net (Payable)/Receivable Impact of rating downgrade trigger: Falls below A3/A- (1) $ 50,460 $ (10,748 ) $ — $ (10,748 ) Falls below Baa1/BBB+ 6,989,288 (471,249 ) — (471,249 ) Falls to or below Baa2/BBB (2) 558,159 (20,778 ) — (20,778 ) Falls below Baa3/BBB- 221,473 (14,759 ) — (14,759 ) Total $ 7,819,380 $ (517,534 ) $ — $ (517,534 ) ____________________________ (1) Rating trigger for CFC falls below A3/A-, while rating trigger for counterparty falls below Baa1/BBB+ by Moody’s or S&P, respectively. (2) Rating trigger for CFC falls to or below Baa2/BBB, while rating trigger for counterparty falls to or below Ba2/BB+ by Moody’s or S&P, respectively. We have outstanding notional amount of derivatives with one counterparty subject to a ratings trigger and early termination provision in the event of a downgrade of CFC’s senior unsecured credit ratings below Baa3, BBB- or BBB- by Moody’s, S&P or Fitch, respectively, which is not included in the above table, totaling $165 million as of August 31, 2019 . These contracts were in an unrealized loss position of $41 million as of August 31, 2019 . Our largest counterparty exposure, based on the outstanding notional amount, accounted for approximately 23% of the total outstanding notional amount of derivatives as of both August 31, 2019 and May 31, 2019 . The aggregate fair value amount, including the credit valuation adjustment, of all interest rate swaps with rating triggers that were in a net liability position was $543 million as of August 31, 2019 .

Equity - (Notes)

Equity - (Notes)	3 Months Ended
	Aug. 31, 2019
Stockholders' Equity Note [Abstract]
Equity	NOTE 10—EQUITY Total equity decreased by $385 million to $918 million as of August 31, 2019 . The decrease was primarily attributable to our reported net loss of $324 million for the three months ended August 31, 2019 and the CFC Board of Directors authorization in the current quarter to retire patronage capital of $63 million . In July 2019 , the CFC Board of Directors authorized the allocation of the fiscal year 2019 net earnings as follows: $97 million to members in the form of patronage, $71 million to the members’ capital reserve and $1 million to the cooperative educational fund. The amount of patronage capital allocated each year by CFC’s Board of Directors is based on adjusted net income, which excludes the impact of derivative forward value gains (losses). See “MD&A—Non-GAAP Financial Measures” for information on adjusted net income. In July 2019 , the CFC Board of Directors authorized the retirement of allocated net earnings totaling $63 million , consisting of $48 million , which represented 50% of the patronage capital allocation for fiscal year 2019 , and $15 million , which represented the portion of the allocation from fiscal year 1994 net earnings that has been held for 25 years pursuant to the CFC Board of Directors policy. This amount was returned to members in cash in September 2019. The remaining portion of the amount allocated for fiscal year 2019 will be retained by CFC for 25 years under current guidelines adopted by the CFC Board of Directors in June 2009. The CFC Board of Directors is required to make annual allocations of adjusted net income, if any. CFC has made annual retirements of allocated net earnings in 39 of the last 40 fiscal years; however, future retirements of allocated amounts are determined based on CFC’s financial condition. The CFC Board of Directors has the authority to change the current practice for allocating and retiring net earnings at any time, subject to applicable laws. See “Item 1. Business—Allocation and Retirement of Patronage Capital” of our 2019 Form 10-K for additional information. Accumulated Other Comprehensive Income (Loss) The following tables summarize, by component, the activity in AOCI as of and for the three months ended August 31, 2019 and 2018 . Three Months Ended August 31, 2019 (Dollars in thousands) Unrealized Gains (Losses) Equity Securities Unrealized Gains Derivatives (1 ) Unrealized Gains (Losses) Cash Flow Hedges Unrealized Losses Defined Benefit Plan ( 2) Total Beginning balance $ — $ 2,571 $ — $ (2,718 ) $ (147 ) (Gains) losses reclassified into earnings — (112 ) — 145 33 Ending balance $ — $ 2,459 $ — $ (2,573 ) $ (114 ) Three Months Ended August 31, 2018 (Dollars in thousands) Unrealized Gains (Losses) Equity Securities Unrealized Gains Derivatives (1) Unrealized Gains (Losses) Cash Flow Hedges Unrealized Losses Defined Benefit Plan ( 2) Total Beginning balance $ 8,794 $ 3,039 $ (1,059 ) $ (2,230 ) $ 8,544 Cumulative effect of changes from adoption of new accounting standards (8,794 ) — — — (8,794 ) Unrealized gains — — 24 — 24 (Gains) losses reclassified into earnings — (119 ) — 131 12 Other comprehensive income (loss) — (119 ) 24 131 36 Ending balance $ — $ 2,920 $ (1,035 ) $ (2,099 ) $ (214 ) ____________________________ (1) Amounts are reclassified into income in the derivative forward value gains (losses) component of the derivative gains (losses) line item of our condensed consolidated statements of operations. (2) Amounts are reclassified into income in the other general and administrative expenses line item of our condensed consolidated statements of operations. We expect to reclassify less than $1 million of amounts in AOCI related to unrealized derivative gains into earnings over the next 12 months.

Guarantees - (Notes)

Guarantees - (Notes)	3 Months Ended
	Aug. 31, 2019
Guarantees [Abstract]
Guarantees	NOTE 11—GUARANTEES The following table summarizes total guarantees, by type of guarantee and by member class, as of August 31, 2019 and May 31, 2019 . (Dollars in thousands) August 31, 2019 May 31, 2019 Total by type: Long-term tax-exempt bonds (1) $ 311,590 $ 312,190 Letters of credit (2) 342,831 379,001 Other guarantees 146,906 146,244 Total $ 801,327 $ 837,435 Total by member class: CFC: Distribution $ 242,630 $ 235,919 Power supply 542,060 586,717 Statewide and associate 5,298 4,708 CFC total 789,988 827,344 NCSC 9,765 8,517 RTFC 1,574 1,574 Total $ 801,327 $ 837,435 ____________________________ (1) Represents the outstanding principal amount of long-term fixed-rate and variable-rate guaranteed bonds. (2) Reflects our maximum potential exposure for letters of credit. Long-term tax-exempt bonds of $312 million as of both August 31, 2019 and May 31, 2019 included $247 million of adjustable or variable-rate bonds that may be converted to a fixed rate as specified in the applicable indenture for each bond offering. We are unable to determine the maximum amount of interest that we may be required to pay related to the remaining adjustable and variable-rate bonds. Many of these bonds have a call provision that allows us to call the bond in the event of a default, which would limit our exposure to future interest payments on these bonds. Our maximum potential exposure generally is secured by mortgage liens on the members’ assets and future revenue. If a member’s debt is accelerated because of a determination that the interest thereon is not tax-exempt, the member’s obligation to reimburse us for any guarantee payments will be treated as a long-term loan. The remaining long-term tax-exempt bonds of $65 million as of August 31, 2019 are fixed-rate. The maximum potential exposure for these bonds, including the outstanding principal of $65 million and related interest through maturity, totaled $90 million as of August 31, 2019 . The maturities for long-term tax-exempt bonds and the related guarantees extend through calendar year 2042. Of the outstanding letters of credit of $343 million and $379 million as of August 31, 2019 and May 31, 2019 , respectively, $104 million and $126 million , respectively, were secured. We did not have any letters of credit outstanding that provided for standby liquidity for adjustable and floating-rate tax-exempt bonds issued for the benefit of our members as of August 31, 2019 . The maturities for the outstanding letters of credit as of August 31, 2019 extend through calendar year 2039. In addition to the letters of credit listed in the table above, under master letter of credit facilities in place as of August 31, 2019 , we may be required to issue up to an additional $57 million in letters of credit to third parties for the benefit of our members. All of our master letter of credit facilities were subject to material adverse change clauses at the time of issuance as of August 31, 2019 . Prior to issuing a letter of credit, we would confirm that there has been no material adverse change in the business or condition, financial or otherwise, of the borrower since the time the loan was approved and confirm that the borrower is currently in compliance with the letter of credit terms and conditions. The maximum potential exposure for other guarantees was $147 million as of both August 31, 2019 and May 31, 2019 of which $25 million was secured as of both August 31, 2019 and May 31, 2019 . The maturities for these other guarantees listed in the table above extend through calendar year 2025. Guarantees under which our right of recovery from our members was not secured totaled $360 million and $374 million and represented 45% of total guarantees as of both August 31, 2019 and May 31, 2019 . In addition to the guarantees described above, we were also the liquidity provider for $247 million of variable-rate tax-exempt bonds as of August 31, 2019 , issued for our member cooperatives. While the bonds are in variable-rate mode, in return for a fee, we have unconditionally agreed to purchase bonds tendered or put for redemption if the remarketing agents are unable to sell such bonds to other investors. We were not required to perform as liquidity provider pursuant to these obligations during the three months ended August 31, 2019 or the prior fiscal year. Guarantee Liability As of both August 31, 2019 and May 31, 2019 , we recorded a guarantee liability of $14 million which represents the contingent and noncontingent exposures related to guarantees and liquidity obligations. The contingent guarantee liability was $1 million as of both August 31, 2019 and May 31, 2019 , based on management’s estimate of exposure to losses within the guarantee portfolio. The remaining balance of the total guarantee liability of $13 million as of both August 31, 2019 and May 31, 2019 , respectively, relates to our noncontingent obligation to stand ready to perform over the term of our guarantees and liquidity obligations that we have entered into or modified since January 1, 2003.

Fair Value Measurement - (Notes

Fair Value Measurement - (Notes)	3 Months Ended
	Aug. 31, 2019
Fair Value Disclosures [Abstract]
Fair Value Measurement	NOTE 12—FAIR VALUE MEASUREMENT We use fair value measurements for the initial recording of certain assets and liabilities and periodic remeasurement of certain assets and liabilities on a recurring or nonrecurring basis. The accounting guidance for fair value measurements and disclosures establishes a three-level fair value hierarchy that prioritizes the inputs into the valuation techniques used to measure fair value. The levels of the fair value hierarchy, in priority order, include Level 1, Level 2 and Level 3. For additional information regarding the fair value hierarchy and a description of the methodologies we use to measure fair value, see “Note 14—Fair Value Measurement” to the Consolidated Financial Statements in our 2019 Form 10-K. The following tables present the carrying value and fair value for all of our financial instruments, including those carried at amortized cost, as of August 31, 2019 and May 31, 2019 . The tables also display the classification within the fair value hierarchy of the valuation technique used in estimating fair value. August 31, 2019 Fair Value Measurement Level (Dollars in thousands) Carrying Value Fair Value Level 1 Level 2 Level 3 Assets: Cash and cash equivalents $ 231,050 $ 231,050 $ 231,050 $ — $ — Restricted cash 9,138 9,138 9,138 — — Equity securities 63,922 63,922 63,922 — — Debt securities held-to-maturity 569,575 580,476 — 580,476 — Deferred compensation investments 5,923 5,923 5,923 — — Loans to members, net 26,282,273 28,353,451 — — 28,353,451 Accrued interest receivable 133,119 133,119 — 133,119 — Debt service reserve funds 17,151 17,151 17,151 — — Derivative assets 85,533 85,533 — 85,533 — Liabilities: Short-term borrowings $ 4,027,645 $ 4,028,391 $ — $ 4,028,391 $ — Long-term debt 19,094,236 20,650,260 — 11,840,788 8,809,472 Accrued interest payable 209,931 209,931 — 209,931 — Guarantee liability 13,514 13,406 — — 13,406 Derivative liabilities 820,872 820,872 — 820,872 — Subordinated deferrable debt 985,981 1,055,555 — 1,055,555 — Members’ subordinated certificates 1,356,485 1,356,485 — — 1,356,485 May 31, 2019 Fair Value Measurement Level (Dollars in thousands) Carrying Value Fair Value Level 1 Level 2 Level 3 Assets: Cash and cash equivalents $ 177,922 $ 177,922 $ 177,922 $ — $ — Restricted cash 8,282 8,282 8,282 — — Equity securities 87,533 87,533 87,533 — — Debt securities held-to-maturity 565,444 570,549 — 570,549 — Deferred compensation investments 4,984 4,984 4,984 — — Loans to members, net 25,899,369 25,743,503 — — 25,743,503 Accrued interest receivable 133,605 133,605 — 133,605 — Debt service reserve funds 17,151 17,151 17,151 — — Derivative assets 41,179 41,179 — 41,179 — Liabilities: Short-term borrowings $ 3,607,726 $ 3,608,259 $ — $ 3,608,259 $ — Long-term debt 19,210,793 20,147,183 — 11,482,715 8,664,468 Accrued interest payable 158,997 158,997 — 158,997 — Guarantee liability 13,666 13,307 — — 13,307 Derivative liabilities 391,724 391,724 — 391,724 — Subordinated deferrable debt 986,020 1,004,707 — 1,004,707 — Members’ subordinated certificates 1,357,129 1,357,129 — — 1,357,129 Transfers Between Levels We monitor the availability of observable market data to assess the appropriate classification of financial instruments within the fair value hierarchy and transfer between Level 1, Level 2, and Level 3 accordingly. Observable market data includes but is not limited to quoted prices and market transactions. Changes in economic conditions or market liquidity generally will drive changes in availability of observable market data. Changes in availability of observable market data, which also may result in changes in the valuation technique used, are generally the cause of transfers between levels. We did not have any transfers between levels for financial instruments measured at fair value on a recurring basis for the three months ended August 31, 2019 and 2018 . Recurring Fair Value Measurements The following table presents the carrying value and fair value of financial instruments reported in our condensed consolidated financial statements at fair value on a recurring basis as of August 31, 2019 and May 31, 2019 , and the classification of the valuation technique within the fair value hierarchy. August 31, 2019 May 31, 2019 (Dollars in thousands) Level 1 Level 2 Total Level 1 Level 2 Total Equity securities $ 63,922 $ — $ 63,922 $ 87,533 $ — $ 87,533 Deferred compensation investments 5,923 — 5,923 4,984 — 4,984 Derivative assets — 85,533 85,533 — 41,179 41,179 Derivative liabilities — 820,872 820,872 — 391,724 391,724 Nonrecurring Fair Value We may be required, from time to time, to measure certain assets at fair value on a nonrecurring basis on our condensed consolidated balance sheets. These assets are not measured at fair value on an ongoing basis but are subject to fair value adjustments in certain circumstances, such as in the application of lower of cost or fair value accounting or when we evaluate for impairment. Assets measured at fair value on a nonrecurring basis and still held during the three months ended August 31, 2019 and 2018 consisted of certain impaired loans. Fair value measurement adjustments for individually impaired loans are recorded in the provision for loan losses on our condensed consolidated statements of operations. The fair value of these assets is determined based on the use of significant unobservable inputs, which are considered Level 3 in the fair value hierarchy. We did not have any nonrecurring fair value measurement adjustments recorded in earnings attributable to these assets during the three months ended August 31, 2019 and 2018 . Significant Unobservable Level 3 Inputs Impaired Loans The fair value of impaired loans is typically measured based on the present value of expected future cash flows. Our estimate of expected future cash flows incorporates, among other items, assumptions regarding default rates, loss severities, the amounts and timing of prepayments, as well as the characteristics of the loan. If we expect repayment to be provided solely by the continued operation or sale of the underlying collateral, the fair value of the collateral less estimated costs to sell is used as the basis for measuring fair value. We employ various approaches and techniques to determine the fair value of collateral-dependent loans, including developing market multiples and obtaining valuations from third-party specialists. The significant unobservable inputs used in measuring the fair value of collateral-dependent loans include estimated cash flows before interest, taxes, depreciation and amortization and market multiples for comparable companies. Our Credit Risk Management group reviews the unobservable inputs to assess the reasonableness of the assumptions used and the accuracy of the work performed. We did not have any impaired collateral-dependent loans as of August 31, 2019 or May 31, 2019.

Business Segments - (Notes)

Business Segments - (Notes)	3 Months Ended
	Aug. 31, 2019
Segment Reporting [Abstract]
Segment Information	NOTE 13—BUSINESS SEGMENTS The following tables display segment results for the three months ended August 31, 2019 and 2018 , and assets attributable to each segment as of August 31, 2019 and August 31, 2018 . Three Months Ended August 31, 2019 (Dollars in thousands) CFC Other Elimination Consolidated Total Statement of operations: Interest income $ 287,964 $ 12,347 $ (10,296 ) $ 290,015 Interest expense (213,135 ) (10,432 ) 10,296 (213,271 ) Net interest income 74,829 1,915 — 76,744 Provision for loan losses (30 ) — — (30 ) Net interest income after provision for loan losses 74,799 1,915 — 76,714 Non-interest income: Fee and other income 12,282 7,821 (9,162 ) 10,941 Derivative losses: Derivative cash settlements expense (10,801 ) (242 ) — (11,043 ) Derivative forward value losses (382,762 ) (1,920 ) — (384,682 ) Derivative losses (393,563 ) (2,162 ) — (395,725 ) Unrealized gains on equity securities 1,620 — — 1,620 Total non-interest income (379,661 ) 5,659 (9,162 ) (383,164 ) Non-interest expense: General and administrative expenses (24,739 ) (2,235 ) 1,645 (25,329 ) Other non-interest (expense) income 7,179 (7,517 ) 7,517 7,179 Total non-interest expense (17,560 ) (9,752 ) 9,162 (18,150 ) Loss before income taxes (322,422 ) (2,178 ) — (324,600 ) Income tax benefit — 521 — 521 Net loss $ (322,422 ) $ (1,657 ) $ — $ (324,079 ) August 31, 2019 CFC Other Elimination Consolidated Total Assets: Total loans outstanding $ 26,258,810 $ 1,048,892 $ (1,019,103 ) $ 26,288,599 Deferred loan origination costs 11,239 — — 11,239 Loans to members 26,270,049 1,048,892 (1,019,103 ) 26,299,838 Less: Allowance for loan losses (17,565 ) — — (17,565 ) Loans to members, net 26,252,484 1,048,892 (1,019,103 ) 26,282,273 Other assets 1,286,409 105,290 (95,216 ) 1,296,483 Total assets $ 27,538,893 $ 1,154,182 $ (1,114,319 ) $ 27,578,756 Three Months Ended August 31, 2018 (Dollars in thousands) CFC Other Elimination Consolidated Total Statement of operations: Interest income $ 276,243 $ 12,984 $ (10,736 ) $ 278,491 Interest expense (210,050 ) (10,917 ) 10,736 (210,231 ) Net interest income 66,193 2,067 — 68,260 Benefit for loan losses 109 — — 109 Net interest income after benefit for loan losses 66,302 2,067 — 68,369 Non-interest income: Fee and other income 5,199 564 (1,852 ) 3,911 Derivative gains (losses): Derivative cash settlements expense (12,562 ) (267 ) — (12,829 ) Derivative forward value gains 19,671 341 — 20,012 Derivative gains 7,109 74 — 7,183 Unrealized losses on equity securities (726 ) — — (726 ) Total non-interest income 11,582 638 (1,852 ) 10,368 Non-interest expense: General and administrative expenses (22,425 ) (2,374 ) 1,594 (23,205 ) Losses on early extinguishment of debt (7,100 ) — — (7,100 ) Other non-interest expense (394 ) (258 ) 258 (394 ) Total non-interest expense (29,919 ) (2,632 ) 1,852 (30,699 ) Income before income taxes 47,965 73 — 48,038 Income tax expense — (60 ) — (60 ) Net income $ 47,965 $ 13 $ — $ 47,978 August 31, 2018 CFC Other Elimination Consolidated Total Assets: Total loans outstanding $ 25,138,742 $ 1,139,507 $ (1,106,813 ) $ 25,171,436 Deferred loan origination costs 11,218 — — 11,218 Loans to members 25,149,960 1,139,507 (1,106,813 ) 25,182,654 Less: Allowance for loan losses (18,692 ) — — (18,692 ) Loans to members, net 25,131,268 1,139,507 (1,106,813 ) 25,163,962 Other assets 1,501,315 106,902 (95,972 ) 1,512,245 Total assets $ 26,632,583 $ 1,246,409 $ (1,202,785 ) $ 26,676,207

Summary of Significant Accoun_2

Summary of Significant Accounting Policies - (Policies)	3 Months Ended
	Aug. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
The Company	The Company National Rural Utilities Cooperative Finance Corporation (“CFC”) is a member-owned cooperative association incorporated under the laws of the District of Columbia in April 1969. CFC’s principal purpose is to provide its members with financing to supplement the loan programs of the Rural Utilities Service (“RUS”) of the United States Department of Agriculture (“USDA”). CFC makes loans to its rural electric members so they can acquire, construct and operate electric distribution systems, generation and transmission (“power supply”) systems and related facilities. CFC also provides its members with credit enhancements in the form of letters of credit and guarantees of debt obligations. As a cooperative, CFC is owned by and exclusively serves its membership, which consists of not-for-profit entities or subsidiaries or affiliates of not-for-profit entities. CFC is exempt from federal income taxes.
Basis of Presentation	Basis of Presentation and Use of Estimates The accompanying unaudited interim condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States (“GAAP”).
Use of Estimates	The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts and related disclosures during the period. Management’s most significant estimates and assumptions involve determining the allowance for loan losses and the fair value of financial assets and liabilities. Actual results could differ from these estimates. We believe these financial statements reflect all adjustments of a normal, recurring nature that are, in the opinion of management, necessary for the fair presentation of the results for the interim period. The results of operations for interim periods are not necessarily indicative of results for the entire fiscal year. Certain reclassifications have been made to prior periods to conform to the current presentation.
Principles of Consolidation	Principles of Consolidation The accompanying condensed consolidated financial statements include the accounts of CFC, variable interest entities (“VIEs”) where CFC is the primary beneficiary and subsidiary entities created and controlled by CFC to hold foreclosed assets. CFC did no t have any entities that held foreclosed assets as of August 31, 2019 or May 31, 2019 . All intercompany balances and transactions have been eliminated. National Cooperative Services Corporation (“NCSC”) and Rural Telephone Finance Cooperative (“RTFC”) are VIEs that are required to be consolidated by CFC. NCSC is a taxable member-owned cooperative that may provide financing to members of CFC, government or quasi-government entities which own electric utility systems that meet the Rural Electrification Act definition of “rural,” and for-profit and nonprofit entities that are owned, operated or controlled by, or provide significant benefits to certain members of CFC. RTFC is a taxable Subchapter T cooperative association that provides financing for its rural telecommunications members and their affiliates. Unless stated otherwise, references to “we,” “our” or “us” relate to CFC and its consolidated entities.
Restricted Cash	Restricted Cash Restricted cash, which consists primarily of member funds held in escrow for certain specifically designed cooperative programs, totaled $9 million and $8 million as of August 31, 2019 and May 31, 2019 , respectively.
Assets Held for Sale	Assets Held for Sale On March 14, 2018, CFC entered into a purchase and sale agreement (“the agreement”), which was subsequently amended, for the sale of a parcel of land, consisting of approximately 28 acres, located in Loudoun County, Virginia. We designated the property, which had a carrying value of $14 million , as held for sale and reclassified it from fixed assets, net to other assets on our consolidated balance sheet. On July 22, 2019, we closed on the sale of the land and received net proceeds of $22 million , resulting in a gain of $8 million on the sale of this property, which is reported in other non-interest income (expense) on our condensed consolidated statements of operations.
Revenue Recognition, Interest	The following table presents interest income, by interest-earning asset category, for the three months ended August 31, 2019 and 2018 . Three Months Ended August 31, (Dollars in thousands) 2019 2018 Interest income by interest-earning asset type: Long-term fixed-rate loans (1) $ 258,478 $ 251,801 Long-term variable-rate loans 9,756 9,381 Line of credit loans 16,033 11,633 TDR loans (2) 206 218 Other income, net (3) (284 ) (325 ) Total loans 284,189 272,708 Cash, time deposits and investment securities 5,826 5,783 Total interest income $ 290,015 $ 278,491 ____________________________ (1) Includes loan conversion fees, which are generally deferred and recognized as interest income using the effective interest method. (2) Troubled debt restructured (“TDR”) loans. (3) Consists of late payment fees, commitment fees and net amortization of deferred loan fees and loan origination costs. Deferred income of $56 million and $58 million as of August 31, 2019 and May 31, 2019 , respectively, consists primarily of deferred loan conversion fees totaling $50 million and $52 million , respectively. Deferred loan conversion fees are recognized in interest income using the effective interest method.
Interest Expense, Policy	The following table presents interest expense, by debt product type, for the three months ended August 31, 2019 and 2018 . Three Months Ended August 31, (Dollars in thousands) 2019 2018 Interest expense by debt product type: (1)(2) Short-term borrowings $ 22,822 $ 19,419 Medium-term notes 32,076 32,410 Collateral trust bonds 65,381 77,705 Guaranteed Underwriter Program notes payable 40,433 35,334 Farmer Mac notes payable 25,074 21,111 Other notes payable 254 322 Subordinated deferrable debt 12,882 9,417 Subordinated certificates 14,349 14,513 Total interest expense $ 213,271 $ 210,231 ____________________________ (1) Includes amortization of debt discounts and debt issuance costs, which are generally deferred and recognized as interest expense using the effective interest method. Issuance costs related to dealer commercial paper, however, are recognized as interest expense immediately as incurred. (2) Includes fees related to funding arrangements, such as up-front fees paid to banks participating in our committed bank revolving line of credit agreements. Depending on the nature of the fee, amounts may be deferred and recognized as interest expense ratably over the term of the arrangement or recognized immediately as incurred.
Recent Accounting Changes and Other Developments	Recent Accounting Changes and Other Developments Accounting Standards Adopted in Fiscal Year 2020 Derivatives and Hedging—Targeted Improvements to Accounting for Hedging Activities In August 2017, the FASB issued ASU 2017-12, Derivatives and Hedging—Targeted Improvements to Accounting for Hedging Acti vities, which expands the types of risk management strategies that qualify for hedge accounting treatment to more closely align the results of hedge accounting with the economics of certain risk management activities and simplifies certain hedge documentation and assessment requirement. It also eliminates the concept of separately recording hedge ineffectiveness and expands disclosure requirements. The guidance is effective for public entities for fiscal years beginning after December 15, 2018, including interim periods within those years. Early adoption is permitted in any interim period or fiscal year before the effective date. We adopted this guidance on June 1, 2019. Hedge accounting is elective, and we currently apply hedge accounting on a limited basis, specifically when we enter into treasury rate lock agreements. The adoption of this guidance did not have an impact on our consolidated financial statements or cash flows. If we continue to elect not to apply hedge accounting to our interest rate swaps, the guidance will not have an impact on our consolidated financial statements or cash flows. Receivables—Nonrefundable Fees and Other Cost In March 2017, the FASB issued ASU 2017-08, Receivables—Nonrefundable Fees and Other Costs, which shortens the amortization period for the premium on certain callable debt securities to the earliest call date rather the maturity date. The guidance is applicable to any individual debt security, purchased at a premium, with an explicit and noncontingent call feature with a fixed price on a preset date. The guidance does not impact the accounting for purchased callable debt securities held at a discount. The guidance is effective for public entities in fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. We adopted this guidance on June 1, 2019. The adoption of this guidance did not have a material impact on our consolidated financial statements or cash flows. Leases In February 2016, the FASB issued ASU 2016-02, Leases, which provides new guidance that is intended to improve financial reporting about leasing transactions. The new guidance requires the recognition of a right-of use asset and lease liability on the consolidated balance sheet by lessees for those leases classified as operating leases under previous guidance. It also requires new disclosures to help investors and other financial statement users better understand the amount, timing, and uncertainty of cash flows arising from leases. The guidance is effective for fiscal years and interim periods within those fiscal years beginning after December 15, 2018. We adopted this guidance on June 1, 2019. The adoption of this guidance did not have a material impact on our consolidated financial statements or cash flows. Accounting Standards Issued But Not Yet Adopted Fair Value Measurement—Changes to the Disclosure Requirements for Fair Value Measurement In August 2018, the FASB issued ASU 2018-13, Fair Value Measurement—Changes to the Disclosure Requirements for Fair Value Measurement, which eliminates, adds and modifies certain disclosure requirements for fair value measurements as part of its disclosure framework project. The guidance is effective for public entities for fiscal years beginning after December 15, 2019, including interim periods within those years. Early adoption is permitted in any interim period or fiscal year before the effective date. The guidance is effective for us beginning June 1, 2020. We do not expect that the adoption of this guidance will have a material impact on our consolidated financial statements or cash flows. Financial Instruments—Credit Losses: Measurement of Credit Losses on Financial Instruments In June 2016, the FASB issued ASU 2016-13, Financial Instruments—Credit Losses: Measurement of Credit Losses on Financial Instruments, which replaces the existing incurred credit loss model and establishes a single credit loss framework based on a current expected credit loss model for financial assets carried at amortized cost, including loans and held-to- maturity debt securities. The current expected loss model requires an entity to estimate credit losses expected over the life of the credit exposure upon initial recognition of that exposure when the financial asset is originated or acquired, which will generally result in earlier recognition of credit losses. The guidance also amends the other-than-temporary model for available-for-sale debt securities by requiring the use of an allowance, rather than directly reducing the carrying value of the security. The new guidance also requires expanded credit quality disclosures. The new guidance is effective for fiscal years and interim periods within those fiscal years, beginning after December 15, 2019. This guidance is effective for us on June 1, 2020. While early adoption is permitted, we do not expect to elect that option. We are continuing to evaluate the impact of the guidance on our consolidated financial statements, including assessing and evaluating assumptions and models to estimate losses. Upon adoption of the guidance on June 1, 2020, we will be required to record a cumulative effect adjustment to retained earnings for the impact as of the date of adoption. The impact will depend on our portfolio composition and credit quality at the date of adoption, as well as forecasts at that time.
Derivatives	Accounting for Derivatives In accordance with the accounting standards for derivatives and hedging activities, we record derivative instruments at fair value as either a derivative asset or derivative liability on our condensed consolidated balance sheets. We report derivative asset and liability amounts on a gross basis based on individual contracts, which does not take into consideration the effects of master netting agreements or collateral netting. Our derivatives transactions are not collateralized and do not include collateralization agreements with counterparties. Derivatives in a gain position are reported as derivative assets on our condensed consolidated balance sheets, while derivatives in a loss position are reported as derivative liabilities. Accrued interest related to derivatives is reported on our condensed consolidated balance sheets as a component of either accrued interest receivable or accrued interest payable. If we do not elect hedge accounting treatment, changes in the fair value of derivative instruments, which consist of net accrued periodic derivative cash settlements expense and derivative forward value amounts, are recognized in our condensed consolidated statements of operations under derivative gains (losses). If we elect hedge accounting treatment for derivatives, we formally document, designate and assess the effectiveness of the hedge relationship. Changes in the fair value of derivatives designated as qualifying fair value hedges are recognized in the same line item on our condensed consolidated statements of operations as the earnings effect of the related hedged item. Changes in the fair value of derivatives designated as qualifying cash flow hedges are recorded as a component of AOCI. Those amounts are reclassified into earnings in the same period during which the forecasted transaction impacts earnings and presented in the same line item on our condensed consolidated statements of operations as the earnings effect of the related hedged item. We generally do not designate interest rate swaps, which represented all of our outstanding derivatives as of August 31, 2019 , for hedge accounting. Accordingly, changes in the fair value of interest rate swaps are reported in our condensed consolidated statements of operations under derivative gains (losses). Net periodic cash settlements expense related to interest rate swaps are classified as an operating activity in our consolidated statements of cash flows.
Fair Value Measurement	We use fair value measurements for the initial recording of certain assets and liabilities and periodic remeasurement of certain assets and liabilities on a recurring or nonrecurring basis. The accounting guidance for fair value measurements and disclosures establishes a three-level fair value hierarchy that prioritizes the inputs into the valuation techniques used to measure fair value. The levels of the fair value hierarchy, in priority order, include Level 1, Level 2 and Level 3. For additional information regarding the fair value hierarchy and a description of the methodologies we use to measure fair value, see “Note 14—Fair Value Measurement” to the Consolidated Financial Statements in our 2019 Form 10-K.
Impaired loans	Impaired Loans The fair value of impaired loans is typically measured based on the present value of expected future cash flows. Our estimate of expected future cash flows incorporates, among other items, assumptions regarding default rates, loss severities, the amounts and timing of prepayments, as well as the characteristics of the loan. If we expect repayment to be provided solely by the continued operation or sale of the underlying collateral, the fair value of the collateral less estimated costs to sell is used as the basis for measuring fair value. We employ various approaches and techniques to determine the fair value of collateral-dependent loans, including developing market multiples and obtaining valuations from third-party specialists. The significant unobservable inputs used in measuring the fair value of collateral-dependent loans include estimated cash flows before interest, taxes, depreciation and amortization and market multiples for comparable companies. Our Credit Risk Management group reviews the unobservable inputs to assess the reasonableness of the assumptions used and the accuracy of the work performed.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies - (Tables)	3 Months Ended
	Aug. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedule of components of interest income	The following table presents interest income, by interest-earning asset category, for the three months ended August 31, 2019 and 2018 . Three Months Ended August 31, (Dollars in thousands) 2019 2018 Interest income by interest-earning asset type: Long-term fixed-rate loans (1) $ 258,478 $ 251,801 Long-term variable-rate loans 9,756 9,381 Line of credit loans 16,033 11,633 TDR loans (2) 206 218 Other income, net (3) (284 ) (325 ) Total loans 284,189 272,708 Cash, time deposits and investment securities 5,826 5,783 Total interest income $ 290,015 $ 278,491 ____________________________ (1) Includes loan conversion fees, which are generally deferred and recognized as interest income using the effective interest method. (2) Troubled debt restructured (“TDR”) loans. (3) Consists of late payment fees, commitment fees and net amortization of deferred loan fees and loan origination costs.
Schedule of Components of Interest (Expense)	The following table presents interest expense, by debt product type, for the three months ended August 31, 2019 and 2018 . Three Months Ended August 31, (Dollars in thousands) 2019 2018 Interest expense by debt product type: (1)(2) Short-term borrowings $ 22,822 $ 19,419 Medium-term notes 32,076 32,410 Collateral trust bonds 65,381 77,705 Guaranteed Underwriter Program notes payable 40,433 35,334 Farmer Mac notes payable 25,074 21,111 Other notes payable 254 322 Subordinated deferrable debt 12,882 9,417 Subordinated certificates 14,349 14,513 Total interest expense $ 213,271 $ 210,231 ____________________________ (1) Includes amortization of debt discounts and debt issuance costs, which are generally deferred and recognized as interest expense using the effective interest method. Issuance costs related to dealer commercial paper, however, are recognized as interest expense immediately as incurred. (2) Includes fees related to funding arrangements, such as up-front fees paid to banks participating in our committed bank revolving line of credit agreements. Depending on the nature of the fee, amounts may be deferred and recognized as interest expense ratably over the term of the arrangement or recognized immediately as incurred.

Variable Interest Entities - (T

Variable Interest Entities - (Tables)	3 Months Ended
	Aug. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedule of Variable Interest Entities	The following table provides information on incremental consolidated assets and liabilities of VIEs included in CFC’s condensed consolidated financial statements, after intercompany eliminations, as of August 31, 2019 and May 31, 2019 . (Dollars in thousands) August 31, 2019 May 31, 2019 Total loans outstanding $ 1,048,892 $ 1,087,988 Other assets 10,074 10,963 Total assets $ 1,058,966 $ 1,098,951 Long-term debt $ 6,000 $ 6,000 Other liabilities 36,878 33,385 Total liabilities $ 42,878 $ 39,385
Schedule of Variable Interest Entities, Credit Commitments	The following table provides information on CFC’s credit commitments to NCSC and RTFC, and its potential exposure to loss as of August 31, 2019 and May 31, 2019 . (Dollars in thousands) August 31, 2019 May 31, 2019 CFC credit commitments $ 5,500,000 $ 5,500,000 Outstanding commitments: Borrowings payable to CFC (1) 1,019,103 1,059,629 Credit enhancements: CFC third-party guarantees 11,339 10,091 Other credit enhancements 16,171 14,251 Total credit enhancements (2) 27,510 24,342 Total outstanding commitments 1,046,613 1,083,971 CFC available credit commitments $ 4,453,387 $ 4,416,029 ____________________________ (1) Borrowings payable to CFC are eliminated in consolidation. (2) Excludes interest due on these instruments.

Investment Securities - (Tables

Investment Securities - (Tables)	3 Months Ended
	Aug. 31, 2019
Investments [Abstract]
Equity Securities	The following table presents the fair value of our equity securities, all of which had readily determinable fair values, as of August 31, 2019 and May 31, 2019 . (Dollars in thousands) August 31, 2019 May 31, 2019 Equity securities at fair value: Farmer Mac—Series A, B and C non-cumulative preferred stock $ 58,166 $ 82,445 Farmer Mac—class A common stock 5,756 5,088 Total equity securities at fair value $ 63,922 $ 87,533
Unrealized Gain (Loss) on Investments	The following tables present the amortized cost and fair value of our debt securities and the corresponding gross unrealized gains and losses, by classification category and major security type, as of August 31, 2019 and May 31, 2019 . August 31, 2019 (Dollars in thousands) Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value Debt securities held-to-maturity: Certificates of deposit $ 6,123 $ 2 $ — $ 6,125 Commercial paper 5,950 — — 5,950 U.S. agency debt securities 4,563 201 — 4,764 Corporate debt securities 481,914 9,426 (219 ) 491,121 Commercial MBS: Agency 7,243 473 — 7,716 Non-agency 3,453 — (5 ) 3,448 Total commercial MBS 10,696 473 (5 ) 11,164 U.S. state and municipality debt securities 9,606 520 — 10,126 Foreign government debt securities 1,257 58 — 1,315 Other ABS (1) 49,466 448 (3 ) 49,911 Total debt securities held-to-maturity $ 569,575 $ 11,128 $ (227 ) $ 580,476 May 31, 2019 (Dollars in thousands) Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value Debt securities held-to-maturity: Certificates of deposit $ 1,000 $ — $ — $ 1,000 Commercial paper 12,395 — — 12,395 U.S. agency debt securities 3,207 108 — 3,315 Corporate debt securities 478,578 4,989 (912 ) 482,655 Commercial MBS: Agency 7,255 291 — 7,546 Non-agency 3,453 — (7 ) 3,446 Total commercial MBS 10,708 291 (7 ) 10,992 U.S. state and municipality debt securities 9,608 352 — 9,960 Foreign government debt securities 1,254 42 — 1,296 Other ABS (1) 48,694 290 (48 ) 48,936 Total debt securities held-to-maturity $ 565,444 $ 6,072 $ (967 ) $ 570,549 ____________________________ (1) Consists primarily of securities backed by auto lease loans, equipment-backed loans, auto loans and credit card loans.
Schedule of Unrealized Loss on Investments	The following table presents the fair value and gross unrealized losses for debt securities in a gross loss position, aggregated by security type, and the length of time the securities have been in a continuous unrealized loss position as of August 31, 2019 and May 31, 2019 . The securities are segregated between investments that have been in a continuous unrealized loss position for less than 12 months and 12 months or more based on the point in time that the fair value declined below the amortized cost basis. August 31, 2019 Unrealized Loss Position Less than 12 Months Unrealized Loss Position 12 Months or Longer Total (Dollars in thousands) Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Debt securities held-to-maturity: Corporate debt securities $ 50,895 $ (75 ) $ 45,650 $ (144 ) $ 96,545 $ (219 ) Commercial MBS, non-agency 3,447 (5 ) — — 3,447 (5 ) Other ABS (1) — — 7,909 (3 ) 7,909 (3 ) Total debt securities held-to-maturity $ 54,342 $ (80 ) $ 53,559 $ (147 ) $ 107,901 $ (227 ) May 31, 2019 Unrealized Loss Position Less than 12 Months Unrealized Loss Position 12 Months or Longer Total (Dollars in thousands) Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Debt securities held-to-maturity: Commercial paper (2) $ 2,688 $ — $ — $ — $ 2,688 $ — Corporate debt securities 45,999 (198 ) 164,086 (714 ) 210,085 (912 ) Commercial MBS, non-agency 1,996 (4 ) 1,448 (3 ) 3,444 (7 ) Other ABS (1) 1,982 (4 ) 13,840 (44 ) 15,822 (48 ) Total debt securities held-to-maturity $ 52,665 $ (206 ) $ 179,374 $ (761 ) $ 232,039 $ (967 ) ____________________________ (1) Consists primarily of securities backed by auto lease loans, equipment-backed loans, auto loans and credit card loans. (2) Unrealized losses on the commercial paper investments are less than $1,000 .
Investments Classified by Contractual Maturity Date	The following table presents, by major security type, the remaining contractual maturity based on amortized cost and fair value of our held-to-maturity investment securities as of August 31, 2019 and May 31, 2019 . Because borrowers may have the right to call or prepay certain obligations, the expected maturities of our investments may differ from the scheduled contractual maturities presented below. August 31, 2019 (Dollars in thousands) Due in 1 Year or Less Due > 1 Year through 5 Years Due > 5 Years through 10 Years Due >10 Years Total Amortized cost: Certificates of deposit $ 5,123 $ 1,000 $ — $ — $ 6,123 Commercial paper 5,950 — — — 5,950 U.S. agency debt securities — 2,682 1,881 — 4,563 Corporate debt securities 61,766 408,037 12,111 — 481,914 Commercial MBS: Agency — 2,078 5,165 — 7,243 Non-agency — — — 3,453 3,453 Total commercial MBS — 2,078 5,165 3,453 10,696 U.S. state and municipality debt securities — 9,606 — — 9,606 Foreign government debt securities — 1,257 — — 1,257 Other ABS (1) — 49,466 — — 49,466 Total $ 72,839 $ 474,126 $ 19,157 $ 3,453 $ 569,575 Fair value: Certificates of deposit $ 5,125 $ 1,000 $ — $ — $ 6,125 Commercial paper 5,950 — — — 5,950 U.S. agency debt securities — 2,811 1,953 — 4,764 Corporate debt securities 61,784 416,655 12,682 — 491,121 Commercial MBS: Agency — 2,210 5,506 — 7,716 Non-Agency — — — 3,448 3,448 Total commercial MBS — 2,210 5,506 3,448 11,164 U.S. state and municipality debt securities — 10,126 — — 10,126 Foreign government debt securities — 1,315 — — 1,315 Other ABS (1) — 49,911 — — 49,911 Total $ 72,859 $ 484,028 $ 20,141 $ 3,448 $ 580,476 Weighted average coupon (2) 2.32 % 3.03 % 3.00 % 3.02 % 2.94 % May 31, 2019 (Dollars in thousands) Due in 1 Year or Less Due > 1 Year through 5 Years Due > 5 Years through 10 Years Due >10 Years Total Amortized cost: Certificates of deposit $ — $ 1,000 $ — $ — $ 1,000 Commercial paper 12,395 — — — 12,395 U.S. agency debt securities — 2,678 529 — 3,207 Corporate debt securities 51,923 414,788 11,867 — 478,578 Commercial MBS: Agency — 310 6,945 — 7,255 Non-agency — — — 3,453 3,453 Total Commercial MBS — 310 6,945 3,453 10,708 U.S. state and municipality debt securities — 9,608 — — 9,608 Foreign government debt securities — 1,254 — — 1,254 Other ABS (1) 510 45,730 2,454 — 48,694 Total $ 64,828 $ 475,368 $ 21,795 $ 3,453 $ 565,444 Fair value: Certificates of deposit $ — $ 1,000 $ — $ — $ 1,000 Commercial paper 12,395 — — — 12,395 U.S. agency debt securities — 2,769 546 — 3,315 Corporate debt securities 51,818 418,606 12,231 — 482,655 Commercial MBS: Agency — 317 7,229 — 7,546 Non-agency — — — 3,446 3,446 Total commercial MBS — 317 7,229 3,446 10,992 U.S. state and municipality debt securities — 9,960 — — 9,960 Foreign government debt securities — 1,296 — — 1,296 Other ABS (1) 509 45,916 2,511 — 48,936 Total $ 64,722 $ 479,864 $ 22,517 $ 3,446 $ 570,549 Weighted average coupon (2) 2.08 % 3.10 % 3.07 % 3.26 % 2.98 % ____________________________ (1) Consists primarily of securities backed by auto lease loans, equipment-backed loans, auto loans and credit card loans. (2) Calculated based on the weighted average coupon rate, which excludes the impact of amortization of premium and accretion of discount.

Loans - (Tables)

Loans - (Tables)	3 Months Ended
	Aug. 31, 2019
Loans and Leases Receivable Disclosure [Abstract]
Summary of loans outstanding to members and unadvanced commitments by loan type and by member class	The following table presents the outstanding principal balance of loans to members, including deferred loan origination costs, and unadvanced loan commitments by loan type and member class, as of August 31, 2019 and May 31, 2019 . August 31, 2019 May 31, 2019 (Dollars in thousands) Loans Outstanding Unadvanced Commitments (1) Loans Outstanding Unadvanced Commitments (1) Loan type: Long-term loans: Fixed rate $ 23,677,234 $ — $ 23,094,253 $ — Variable rate 962,541 5,140,530 1,066,880 5,448,636 Total long-term loans 24,639,775 5,140,530 24,161,133 5,448,636 Lines of credit 1,648,824 7,913,213 1,744,531 7,788,922 Total loans outstanding 26,288,599 13,053,743 25,905,664 13,237,558 Deferred loan origination costs 11,239 — 11,240 — Loans to members $ 26,299,838 $ 13,053,743 $ 25,916,904 $ 13,237,558 Member class: CFC: Distribution $ 20,484,460 $ 8,568,888 $ 20,155,266 $ 8,773,018 Power supply 4,671,035 3,456,266 4,578,841 3,466,680 Statewide and associate 84,212 168,564 83,569 165,687 Total CFC 25,239,707 12,193,718 24,817,676 12,405,385 NCSC 697,791 575,888 742,888 552,840 RTFC 351,101 284,137 345,100 279,333 Total loans outstanding 26,288,599 13,053,743 25,905,664 13,237,558 Deferred loan origination costs 11,239 — 11,240 — Loans to members $ 26,299,838 $ 13,053,743 $ 25,916,904 $ 13,237,558 ____________________________ (1) The interest rate on unadvanced loan commitments is not set until an advance is made; therefore, all long-term unadvanced loan commitments are reported as variable-rate. However, the borrower may select either a fixed or a variable rate when an advance on a commitment is made.
Schedule of available balance and maturities of lines of credit	The following table summarizes the available balance under unadvanced loan commitments as of August 31, 2019 and the related maturities by fiscal year and thereafter by loan type: Available Balance Notional Maturities of Unadvanced Loan Commitments (Dollars in thousands) 2020 2021 2022 2023 2024 Thereafter Line of credit loans $ 7,913,213 $ 609,206 $ 4,128,566 $ 485,285 $ 1,364,426 $ 1,055,813 $ 269,917 Long-term loans 5,140,530 306,460 665,361 1,295,466 1,080,699 1,634,791 157,753 Total $ 13,053,743 $ 915,666 $ 4,793,927 $ 1,780,751 $ 2,445,125 $ 2,690,604 $ 427,670
Summary of available balance under committed lines of credit and the related maturities by fiscal year	The following table summarizes the available balance under unconditional committed lines of credit, and the related maturities by fiscal year and thereafter, as of August 31, 2019 . Available Balance Notional Maturities of Unconditional Committed Lines of Credit (Dollars in thousands) 2020 2021 2022 2023 2024 Thereafter Committed lines of credit $3,003,647 $260,886 $478,489 $171,875 $1,166,687 $811,510 $114,200
Summary of loans outstanding as collateral pledged to secure the entity's collateral trust bonds, Clean Renewable Energy Bonds and notes payable to the Federal Agricultural Mortgage Corporation and the amount of the corresponding debt outstanding	The following table summarizes our loans outstanding as collateral pledged to secure our collateral trust bonds, Clean Renewable Energy Bonds, notes payable to Farmer Mac and notes payable under USDA’s Guaranteed Underwriter Program (“Guaranteed Underwriter Program”) and the amount of the corresponding debt outstanding as of August 31, 2019 and May 31, 2019 . See “Note 6—Short-Term Borrowings” and “Note 7—Long-Term Debt” for information on our borrowings. (Dollars in thousands) August 31, 2019 May 31, 2019 Collateral trust bonds: 2007 indenture: Distribution system mortgage notes $ 8,557,299 $ 8,775,231 RUS-guaranteed loans qualifying as permitted investments 133,129 134,678 Total pledged collateral $ 8,690,428 $ 8,909,909 Collateral trust bonds outstanding 7,622,711 7,622,711 1994 indenture: Distribution system mortgage notes $ 46,522 $ 47,331 Collateral trust bonds outstanding 40,000 40,000 Farmer Mac: Distribution and power supply system mortgage notes $ 3,760,219 $ 3,751,798 Notes payable outstanding 2,962,478 3,054,914 Clean Renewable Energy Bonds Series 2009A: Distribution and power supply system mortgage notes $ 9,799 $ 10,349 Cash 802 415 Total pledged collateral $ 10,601 $ 10,764 Notes payable outstanding 9,225 9,225 Federal Financing Bank: Distribution and power supply system mortgage notes $ 6,127,684 $ 6,157,218 Notes payable outstanding 5,387,155 5,410,507
Schedule of loan portfolio by risk rating category and member class based on available data	The following tables present total loans outstanding, by member class and borrower risk rating category, based on the risk ratings used in the estimation of our allowance for loan losses as of August 31, 2019 and May 31, 2019 . For purposes of these tables and for determining the allowance for loan losses, loans to borrowers that are supported by a full guarantee of repayment by the parent company are grouped in the same risk rating category of the guarantor parent company, rather than the risk rating category of the subsidiary borrower. August 31, 2019 (Dollars in thousands) Pass Special Mention Substandard Doubtful Total CFC: Distribution $ 20,354,654 $ 8,222 $ 121,584 $ — $ 20,484,460 Power supply 4,623,131 — 47,904 — 4,671,035 Statewide and associate 69,212 15,000 — — 84,212 CFC total 25,046,997 23,222 169,488 — 25,239,707 NCSC 697,791 — — — 697,791 RTFC 345,634 — 5,467 — 351,101 Total loans outstanding $ 26,090,422 $ 23,222 $ 174,955 $ — $ 26,288,599 May 31, 2019 (Dollars in thousands) Pass Special Mention Substandard Doubtful Total CFC: Distribution $ 20,022,193 $ 10,375 $ 122,698 $ — $ 20,155,266 Power supply 4,530,708 — 48,133 — 4,578,841 Statewide and associate 68,569 15,000 — — 83,569 CFC total 24,621,470 25,375 170,831 — 24,817,676 NCSC 742,888 — — — 742,888 RTFC 339,508 — 5,592 — 345,100 Total loans outstanding $ 25,703,866 $ 25,375 $ 176,423 $ — $ 25,905,664
Past Due Financing Receivables	The following tables present the payment status of loans outstanding by member class as of August 31, 2019 and May 31, 2019 . As indicated in the table, we did not have any past due loans as of either August 31, 2019 or May 31, 2019 . August 31, 2019 (Dollars in thousands) Current 30-89 Days Past Due 90 Days or More Past Due (1) Total Past Due Total Loans Outstanding Nonaccrual Loans CFC: Distribution $ 20,484,460 $ — $ — $ — $ 20,484,460 $ — Power supply 4,671,035 — — — 4,671,035 — Statewide and associate 84,212 — — — 84,212 — CFC total 25,239,707 — — — 25,239,707 — NCSC 697,791 — — — 697,791 — RTFC 351,101 — — — 351,101 — Total loans outstanding $ 26,288,599 $ — $ — $ — $ 26,288,599 $ — Percentage of total loans 100.00 % — % — % — % 100.00 % — % May 31, 2019 (Dollars in thousands) Current 30-89 Days Past Due 90 Days or More Past Due (1) Total Total Loans Outstanding Nonaccrual Loans CFC: Distribution $ 20,155,266 $ — $ — $ — $ 20,155,266 $ — Power supply 4,578,841 — — — 4,578,841 — Statewide and associate 83,569 — — — 83,569 — CFC total 24,817,676 — — — 24,817,676 — NCSC 742,888 — — — 742,888 — RTFC 345,100 — — — 345,100 — Total loans outstanding $ 25,905,664 $ — $ — $ — $ 25,905,664 $ — Percentage of total loans 100.00 % — % — % — % 100.00 % — % ____________________________ (1) All loans 90 days or more past due are on nonaccrual status.
Schedule of Troubled Debt Restructured loans	The following table provides a summary of loans modified as TDRs in prior periods, the performance status of these loans and the unadvanced loan commitments related to the TDR loans, by member class, as of August 31, 2019 and May 31, 2019 . August 31, 2019 May 31, 2019 (Dollars in thousands) Loans Outstanding % of Total Loans Unadvanced Commitments Loans Outstanding % of Total Loans Unadvanced Commitments TDR loans: Performing TDR loans: CFC/Distribution $ 5,755 0.02 % $ — $ 6,261 0.03 % $ — RTFC 5,467 0.02 — 5,592 0.02 — Total performing TDR loans 11,222 0.04 — 11,853 0.05 — Total TDR loans $ 11,222 0.04 % $ — $ 11,853 0.05 % $ —
Impaired Financing Receivable with Related Allowance Recorded Investment	The following table provides information on loans classified as individually impaired as of August 31, 2019 and May 31, 2019 . August 31, 2019 May 31, 2019 (Dollars in thousands) Recorded Investment Related Allowance Recorded Investment Related Allowance With no specific allowance recorded: CFC $ 5,755 $ — $ 6,261 $ — With a specific allowance recorded: RTFC 5,467 989 5,592 1,021 Total impaired loans $ 11,222 $ 989 $ 11,853 $ 1,021
Schedule of average recorded investment in impaired loans and the interest income recognized by member class	The following table presents, by company, the average recorded investment for individually impaired loans and the interest income recognized on these loans for the three months ended August 31, 2019 and 2018 . Three Months Ended August 31, 2019 2018 2019 2018 (Dollars in thousands) Average Recorded Investment Interest Income Recognized CFC $ 6,239 $ 6,504 $ 137 $ 142 RTFC 5,547 6,048 69 76 Total impaired loans $ 11,786 $ 12,552 $ 206 $ 218

Allowance for Loan Losses - (Ta

Allowance for Loan Losses - (Tables)	3 Months Ended
	Aug. 31, 2019
Loans and Leases Receivable Disclosure [Abstract]
Allowance for Credit Losses on Financing Receivables	The following tables summarize changes, by company, in the allowance for loan losses as of and for the three months ended August 31, 2019 and 2018 . Three Months Ended August 31, 2019 (Dollars in thousands) CFC NCSC RTFC Total Balance as of May 31, 2019 $ 13,120 $ 2,007 $ 2,408 $ 17,535 Provision (benefit) for loan losses (158 ) 70 118 30 Balance as of August 31, 2019 $ 12,962 $ 2,077 $ 2,526 $ 17,565 Three Months Ended August 31, 2018 (Dollars in thousands) CFC NCSC RTFC Total Balance as of May 31, 2018 $ 12,300 $ 2,082 $ 4,419 $ 18,801 Provision (benefit) for loan losses 208 (70 ) (247 ) (109 ) Balance as of August 31, 2018 $ 12,508 $ 2,012 $ 4,172 $ 18,692
Allowance for Credit Losses and Recorded Investment in Financing Receivables	The following tables present, by company, the components of our allowance for loan losses and the recorded investment of the related loans as of August 31, 2019 and May 31, 2019 . August 31, 2019 (Dollars in thousands) CFC NCSC RTFC Total Ending balance of the allowance: Collective allowance $ 12,962 $ 2,077 $ 1,537 $ 16,576 Specific allowance — — 989 989 Total ending balance of the allowance $ 12,962 $ 2,077 $ 2,526 $ 17,565 Recorded investment in loans: Collectively evaluated loans $ 25,233,952 $ 697,791 $ 345,634 $ 26,277,377 Individually evaluated loans 5,755 — 5,467 11,222 Total recorded investment in loans $ 25,239,707 $ 697,791 $ 351,101 $ 26,288,599 Total recorded investment in loans, net (1) $ 25,226,745 $ 695,714 $ 348,575 $ 26,271,034 Allowance coverage ratio: Allowance as a percentage of total recorded investment in loans 0.05 % 0.30 % 0.72 % 0.07 % May 31, 2019 (Dollars in thousands) CFC NCSC RTFC Total Ending balance of the allowance: Collective allowance $ 13,120 $ 2,007 $ 1,387 $ 16,514 Specific allowance — — 1,021 1,021 Total ending balance of the allowance $ 13,120 $ 2,007 $ 2,408 $ 17,535 Recorded investment in loans: Collectively evaluated loans $ 24,811,415 $ 742,888 $ 339,508 $ 25,893,811 Individually evaluated loans 6,261 — 5,592 11,853 Total recorded investment in loans $ 24,817,676 $ 742,888 $ 345,100 $ 25,905,664 Total recorded investment in loans, net (1) $ 24,804,556 $ 740,881 $ 342,692 $ 25,888,129 Allowance coverage ratio: Allowance as a percentage of total recorded investment in loans 0.05 % 0.27 % 0.70 % 0.07 % ____________________________ (1) Excludes unamortized deferred loan origination costs of $11 million as of both August 31, 2019 and May 31, 2019 .

Short-Term Borrowings - (Tables

Short-Term Borrowings - (Tables)	3 Months Ended
	Aug. 31, 2019
Debt Disclosure [Abstract]
Schedule of Short-term Debt	The following table provides comparative information on our short-term borrowings as of August 31, 2019 and May 31, 2019 . (Dollars in thousands) August 31, 2019 May 31, 2019 Short-term borrowings: Commercial paper: Commercial paper sold through dealers, net of discounts $ 829,763 $ 944,616 Commercial paper sold directly to members, at par 1,240,830 1,111,795 Total commercial paper 2,070,593 2,056,411 Select notes to members 1,277,927 1,023,952 Daily liquidity fund notes to members 435,070 298,817 Medium-term notes to members 244,055 228,546 Total short-term borrowings $ 4,027,645 $ 3,607,726
Schedule of Line of Credit Facilities	The following table presents the total commitment, the net amount available for use and the outstanding letters of credit under our committed bank revolving line of credit agreements as of August 31, 2019 and May 31, 2019 . August 31, 2019 May 31, 2019 (Dollars in millions) Total Commitment Letters of Credit Outstanding Net Available for Use Total Commitment Letters of Credit Outstanding Net Available for Use Maturity Annual Facility Fee (1) 3-year agreement $ 1,440 $ — $ 1,440 $ 1,440 $ — $ 1,440 November 28, 2021 7.5 bps 5-year agreement 1,535 3 1,532 1,535 3 1,532 November 28, 2023 10 bps Total $ 2,975 $ 3 $ 2,972 $ 2,975 $ 3 $ 2,972 ____________________________ (1) Facility fee determined by CFC’s senior unsecured credit ratings based on the pricing schedules put in place at the inception of the related agreement.

Long-Term Debt - (Tables)

Long-Term Debt - (Tables)	3 Months Ended
	Aug. 31, 2019
Debt Instruments [Abstract]
Summary of long-term debt outstanding	The following table displays long-term debt outstanding, by debt type, as of August 31, 2019 and May 31, 2019 . (Dollars in thousands) August 31, 2019 May 31, 2019 Secured long-term debt: Collateral trust bonds $ 7,662,711 $ 7,662,711 Unamortized discount (242,123 ) (244,643 ) Debt issuance costs (32,952 ) (34,336 ) Total collateral trust bonds 7,387,636 7,383,732 Guaranteed Underwriter Program notes payable 5,387,155 5,410,507 Farmer Mac notes payable 2,962,478 3,054,914 Other secured notes payable 9,225 9,225 Debt issuance costs (162 ) (178 ) Total other secured notes payable 9,063 9,047 Total secured notes payable 8,358,696 8,474,468 Total secured long-term debt 15,746,332 15,858,200 Unsecured long-term debt: Medium-term notes sold through dealers 2,935,540 2,962,375 Medium-term notes sold to members 418,208 397,080 Subtotal medium-term notes 3,353,748 3,359,455 Unamortized discount (848 ) (931 ) Debt issuance costs (18,492 ) (19,399 ) Total unsecured medium-term notes 3,334,408 3,339,125 Unsecured notes payable 13,701 13,701 Unamortized discount (164 ) (187 ) Debt issuance costs (41 ) (46 ) Total unsecured notes payable 13,496 13,468 Total unsecured long-term debt 3,347,904 3,352,593 Total long-term debt $ 19,094,236 $ 19,210,793

Subordinated Deferrable Debt _2

Subordinated Deferrable Debt - (Tables)	3 Months Ended
	Aug. 31, 2019
Subordinated Debt [Abstract]
Schedule of Subordinated Borrowing	The following table presents subordinated deferrable debt outstanding as of August 31, 2019 and May 31, 2019 . See “Note 8—Subordinated Deferrable Debt” of our 2019 Form 10-K for additional information on the terms of our subordinated deferrable debt outstanding. (Dollars in thousands) August 31, 2019 May 31, 2019 4.75% due 2043 with a call date of April 30, 2023 $ 400,000 $ 400,000 5.25% due 2046 with a call date of April 20, 2026 350,000 350,000 5.50% due 2064 with a call date of May 15, 2024 250,000 250,000 Debt issuance costs (14,019 ) (13,980 ) Total subordinated deferrable debt $ 985,981 $ 986,020

Derivative Instruments and He_2

Derivative Instruments and Hedging Activities - (Tables)	3 Months Ended
	Aug. 31, 2019
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of notional amounts and weighted average rates paid and received	The following table shows the outstanding notional amounts and the weighted-average rate paid and received for our interest rate swaps, by type, as of August 31, 2019 and May 31, 2019 . The substantial majority of our interest rate swaps use an index based on LIBOR for either the pay or receive leg of the swap agreement. August 31, 2019 May 31, 2019 (Dollars in thousands) Notional Amount Weighted- Average Rate Paid Weighted- Average Rate Received Notional Weighted- Weighted- Pay-fixed swaps $ 7,319,015 2.84 % 2.27 % $ 7,379,280 2.83 % 2.60 % Receive-fixed swaps 3,399,000 2.96 2.56 3,399,000 3.25 2.56 Total interest rate swaps 10,718,015 2.88 2.36 10,778,280 2.97 2.58 Forward pay-fixed swaps 65,000 65,000 Total $ 10,783,015 $ 10,843,280
Schedule of fair values and notional amounts of outstanding derivatives	The following table displays the fair value of the derivative assets and derivative liabilities recorded on our condensed consolidated balance sheets and the related outstanding notional amount of our interest rate swaps by derivatives type, as of August 31, 2019 and May 31, 2019 . August 31, 2019 May 31, 2019 (Dollars in thousands) Fair Value Notional Balance Fair Value Notional Balance Derivative assets: Interest rate swaps $ 85,533 $ 2,641,803 $ 41,179 $ 2,332,104 Derivative liabilities: Interest rate swaps $ 820,872 $ 8,141,212 $ 391,724 $ 8,511,176
Schedule of offsetting assets and liabilities	The following table presents the gross fair value of derivative assets and liabilities reported on our condensed consolidated balance sheets as of August 31, 2019 and May 31, 2019 , and provides information on the impact of netting provisions and collateral pledged, if any. August 31, 2019 Gross Amount of Recognized Assets/ Liabilities Gross Amount Offset in the Balance Sheet Net Amount of Assets/ Liabilities Presented in the Balance Sheet Gross Amount Not Offset in the Balance Sheet (Dollars in thousands) Financial Instruments Cash Collateral Pledged Net Amount Derivative assets: Interest rate swaps $ 85,533 $ — $ 85,533 $ 85,533 $ — $ — Derivative liabilities: Interest rate swaps 820,872 — 820,872 85,533 — 735,339 May 31, 2019 Gross Amount of Recognized Assets/ Liabilities Gross Amount Offset in the Balance Sheet Net Amount of Assets/ Liabilities Presented in the Balance Sheet Gross Amount Not Offset in the Balance Sheet (Dollars in thousands) Financial Instruments Cash Collateral Pledged Net Amount Derivative assets: Interest rate swaps $ 41,179 $ — $ 41,179 $ 41,176 $ — $ 3 Derivative liabilities: Interest rate swaps 391,724 — 391,724 41,176 — 350,548
Schedule of offsetting assets and liabilities	The following table presents the gross fair value of derivative assets and liabilities reported on our condensed consolidated balance sheets as of August 31, 2019 and May 31, 2019 , and provides information on the impact of netting provisions and collateral pledged, if any. August 31, 2019 Gross Amount of Recognized Assets/ Liabilities Gross Amount Offset in the Balance Sheet Net Amount of Assets/ Liabilities Presented in the Balance Sheet Gross Amount Not Offset in the Balance Sheet (Dollars in thousands) Financial Instruments Cash Collateral Pledged Net Amount Derivative assets: Interest rate swaps $ 85,533 $ — $ 85,533 $ 85,533 $ — $ — Derivative liabilities: Interest rate swaps 820,872 — 820,872 85,533 — 735,339 May 31, 2019 Gross Amount of Recognized Assets/ Liabilities Gross Amount Offset in the Balance Sheet Net Amount of Assets/ Liabilities Presented in the Balance Sheet Gross Amount Not Offset in the Balance Sheet (Dollars in thousands) Financial Instruments Cash Collateral Pledged Net Amount Derivative assets: Interest rate swaps $ 41,179 $ — $ 41,179 $ 41,176 $ — $ 3 Derivative liabilities: Interest rate swaps 391,724 — 391,724 41,176 — 350,548
Summary of gains and losses recorded on the consolidated statements of operations for the entity's interest rate swaps	The following table presents the components of the derivative gains (losses) reported in our condensed consolidated statements of operations for our interest rate swaps for three months ended August 31, 2019 and 2018 . Three Months Ended August 31, (Dollars in thousands) 2019 2018 Derivative gains (losses) attributable to: Derivative cash settlements expense $ (11,043 ) $ (12,829 ) Derivative forward value gains (losses) (384,682 ) 20,012 Derivative gains (losses) $ (395,725 ) $ 7,183
Schedule of notional amounts of derivative instruments having rating triggers	The following table displays the notional amounts of our derivative contracts with rating triggers as of August 31, 2019 , and the payments that would be required if the contracts were terminated as of that date because of a downgrade of our unsecured credit ratings or the counterparty’s unsecured credit ratings below A3/A-, below Baa1/BBB+, to or below Baa2/BBB, below Baa3/BBB-, or to or below Ba2/BB+ by Moody’s or S&P, respectively. In calculating the payment amounts that would be required upon termination of the derivative contracts, we assumed that the amounts for each counterparty would be netted in accordance with the provisions of the master netting agreements for each counterparty. The net payment amounts are based on the fair value of the underlying derivative instrument, excluding the credit risk valuation adjustment, plus any unpaid accrued interest amounts. (Dollars in thousands) Notional Amount Payable Due from CFC Receivable Due to CFC Net (Payable)/Receivable Impact of rating downgrade trigger: Falls below A3/A- (1) $ 50,460 $ (10,748 ) $ — $ (10,748 ) Falls below Baa1/BBB+ 6,989,288 (471,249 ) — (471,249 ) Falls to or below Baa2/BBB (2) 558,159 (20,778 ) — (20,778 ) Falls below Baa3/BBB- 221,473 (14,759 ) — (14,759 ) Total $ 7,819,380 $ (517,534 ) $ — $ (517,534 ) ____________________________ (1) Rating trigger for CFC falls below A3/A-, while rating trigger for counterparty falls below Baa1/BBB+ by Moody’s or S&P, respectively. (2) Rating trigger for CFC falls to or below Baa2/BBB, while rating trigger for counterparty falls to or below Ba2/BB+ by Moody’s or S&P, respectively.

Equity - (Tables)

Equity - (Tables)	3 Months Ended
	Aug. 31, 2019
Stockholders' Equity Note [Abstract]
Schedule of Accumulated Other Comprehensive Income (Loss)	The following tables summarize, by component, the activity in AOCI as of and for the three months ended August 31, 2019 and 2018 . Three Months Ended August 31, 2019 (Dollars in thousands) Unrealized Gains (Losses) Equity Securities Unrealized Gains Derivatives (1 ) Unrealized Gains (Losses) Cash Flow Hedges Unrealized Losses Defined Benefit Plan ( 2) Total Beginning balance $ — $ 2,571 $ — $ (2,718 ) $ (147 ) (Gains) losses reclassified into earnings — (112 ) — 145 33 Ending balance $ — $ 2,459 $ — $ (2,573 ) $ (114 ) Three Months Ended August 31, 2018 (Dollars in thousands) Unrealized Gains (Losses) Equity Securities Unrealized Gains Derivatives (1) Unrealized Gains (Losses) Cash Flow Hedges Unrealized Losses Defined Benefit Plan ( 2) Total Beginning balance $ 8,794 $ 3,039 $ (1,059 ) $ (2,230 ) $ 8,544 Cumulative effect of changes from adoption of new accounting standards (8,794 ) — — — (8,794 ) Unrealized gains — — 24 — 24 (Gains) losses reclassified into earnings — (119 ) — 131 12 Other comprehensive income (loss) — (119 ) 24 131 36 Ending balance $ — $ 2,920 $ (1,035 ) $ (2,099 ) $ (214 )

Guarantees - (Tables)

Guarantees - (Tables)	3 Months Ended
	Aug. 31, 2019
Guarantees [Abstract]
Summary of total guarantees by type of guarantee and member class	The following table summarizes total guarantees, by type of guarantee and by member class, as of August 31, 2019 and May 31, 2019 . (Dollars in thousands) August 31, 2019 May 31, 2019 Total by type: Long-term tax-exempt bonds (1) $ 311,590 $ 312,190 Letters of credit (2) 342,831 379,001 Other guarantees 146,906 146,244 Total $ 801,327 $ 837,435 Total by member class: CFC: Distribution $ 242,630 $ 235,919 Power supply 542,060 586,717 Statewide and associate 5,298 4,708 CFC total 789,988 827,344 NCSC 9,765 8,517 RTFC 1,574 1,574 Total $ 801,327 $ 837,435 ____________________________ (1) Represents the outstanding principal amount of long-term fixed-rate and variable-rate guaranteed bonds. (2) Reflects our maximum potential exposure for letters of credit.

Fair Value Measurement - (Table

Fair Value Measurement - (Tables)	3 Months Ended
	Aug. 31, 2019
Fair Value Disclosures [Abstract]
Fair Value, by Balance Sheet Grouping	The tables also display the classification within the fair value hierarchy of the valuation technique used in estimating fair value. August 31, 2019 Fair Value Measurement Level (Dollars in thousands) Carrying Value Fair Value Level 1 Level 2 Level 3 Assets: Cash and cash equivalents $ 231,050 $ 231,050 $ 231,050 $ — $ — Restricted cash 9,138 9,138 9,138 — — Equity securities 63,922 63,922 63,922 — — Debt securities held-to-maturity 569,575 580,476 — 580,476 — Deferred compensation investments 5,923 5,923 5,923 — — Loans to members, net 26,282,273 28,353,451 — — 28,353,451 Accrued interest receivable 133,119 133,119 — 133,119 — Debt service reserve funds 17,151 17,151 17,151 — — Derivative assets 85,533 85,533 — 85,533 — Liabilities: Short-term borrowings $ 4,027,645 $ 4,028,391 $ — $ 4,028,391 $ — Long-term debt 19,094,236 20,650,260 — 11,840,788 8,809,472 Accrued interest payable 209,931 209,931 — 209,931 — Guarantee liability 13,514 13,406 — — 13,406 Derivative liabilities 820,872 820,872 — 820,872 — Subordinated deferrable debt 985,981 1,055,555 — 1,055,555 — Members’ subordinated certificates 1,356,485 1,356,485 — — 1,356,485 May 31, 2019 Fair Value Measurement Level (Dollars in thousands) Carrying Value Fair Value Level 1 Level 2 Level 3 Assets: Cash and cash equivalents $ 177,922 $ 177,922 $ 177,922 $ — $ — Restricted cash 8,282 8,282 8,282 — — Equity securities 87,533 87,533 87,533 — — Debt securities held-to-maturity 565,444 570,549 — 570,549 — Deferred compensation investments 4,984 4,984 4,984 — — Loans to members, net 25,899,369 25,743,503 — — 25,743,503 Accrued interest receivable 133,605 133,605 — 133,605 — Debt service reserve funds 17,151 17,151 17,151 — — Derivative assets 41,179 41,179 — 41,179 — Liabilities: Short-term borrowings $ 3,607,726 $ 3,608,259 $ — $ 3,608,259 $ — Long-term debt 19,210,793 20,147,183 — 11,482,715 8,664,468 Accrued interest payable 158,997 158,997 — 158,997 — Guarantee liability 13,666 13,307 — — 13,307 Derivative liabilities 391,724 391,724 — 391,724 — Subordinated deferrable debt 986,020 1,004,707 — 1,004,707 — Members’ subordinated certificates 1,357,129 1,357,129 — — 1,357,129
Schedule of the entity's assets and liabilities that are measured at fair value on a recurring basis	The following table presents the carrying value and fair value of financial instruments reported in our condensed consolidated financial statements at fair value on a recurring basis as of August 31, 2019 and May 31, 2019 , and the classification of the valuation technique within the fair value hierarchy. August 31, 2019 May 31, 2019 (Dollars in thousands) Level 1 Level 2 Total Level 1 Level 2 Total Equity securities $ 63,922 $ — $ 63,922 $ 87,533 $ — $ 87,533 Deferred compensation investments 5,923 — 5,923 4,984 — 4,984 Derivative assets — 85,533 85,533 — 41,179 41,179 Derivative liabilities — 820,872 820,872 — 391,724 391,724

Business Segments - (Tables)

Business Segments - (Tables)	3 Months Ended
	Aug. 31, 2019
Segment Reporting [Abstract]
Schedule of segment presentation for the consolidated statements of operations and consolidated balance sheets	The following tables display segment results for the three months ended August 31, 2019 and 2018 , and assets attributable to each segment as of August 31, 2019 and August 31, 2018 . Three Months Ended August 31, 2019 (Dollars in thousands) CFC Other Elimination Consolidated Total Statement of operations: Interest income $ 287,964 $ 12,347 $ (10,296 ) $ 290,015 Interest expense (213,135 ) (10,432 ) 10,296 (213,271 ) Net interest income 74,829 1,915 — 76,744 Provision for loan losses (30 ) — — (30 ) Net interest income after provision for loan losses 74,799 1,915 — 76,714 Non-interest income: Fee and other income 12,282 7,821 (9,162 ) 10,941 Derivative losses: Derivative cash settlements expense (10,801 ) (242 ) — (11,043 ) Derivative forward value losses (382,762 ) (1,920 ) — (384,682 ) Derivative losses (393,563 ) (2,162 ) — (395,725 ) Unrealized gains on equity securities 1,620 — — 1,620 Total non-interest income (379,661 ) 5,659 (9,162 ) (383,164 ) Non-interest expense: General and administrative expenses (24,739 ) (2,235 ) 1,645 (25,329 ) Other non-interest (expense) income 7,179 (7,517 ) 7,517 7,179 Total non-interest expense (17,560 ) (9,752 ) 9,162 (18,150 ) Loss before income taxes (322,422 ) (2,178 ) — (324,600 ) Income tax benefit — 521 — 521 Net loss $ (322,422 ) $ (1,657 ) $ — $ (324,079 ) August 31, 2019 CFC Other Elimination Consolidated Total Assets: Total loans outstanding $ 26,258,810 $ 1,048,892 $ (1,019,103 ) $ 26,288,599 Deferred loan origination costs 11,239 — — 11,239 Loans to members 26,270,049 1,048,892 (1,019,103 ) 26,299,838 Less: Allowance for loan losses (17,565 ) — — (17,565 ) Loans to members, net 26,252,484 1,048,892 (1,019,103 ) 26,282,273 Other assets 1,286,409 105,290 (95,216 ) 1,296,483 Total assets $ 27,538,893 $ 1,154,182 $ (1,114,319 ) $ 27,578,756 Three Months Ended August 31, 2018 (Dollars in thousands) CFC Other Elimination Consolidated Total Statement of operations: Interest income $ 276,243 $ 12,984 $ (10,736 ) $ 278,491 Interest expense (210,050 ) (10,917 ) 10,736 (210,231 ) Net interest income 66,193 2,067 — 68,260 Benefit for loan losses 109 — — 109 Net interest income after benefit for loan losses 66,302 2,067 — 68,369 Non-interest income: Fee and other income 5,199 564 (1,852 ) 3,911 Derivative gains (losses): Derivative cash settlements expense (12,562 ) (267 ) — (12,829 ) Derivative forward value gains 19,671 341 — 20,012 Derivative gains 7,109 74 — 7,183 Unrealized losses on equity securities (726 ) — — (726 ) Total non-interest income 11,582 638 (1,852 ) 10,368 Non-interest expense: General and administrative expenses (22,425 ) (2,374 ) 1,594 (23,205 ) Losses on early extinguishment of debt (7,100 ) — — (7,100 ) Other non-interest expense (394 ) (258 ) 258 (394 ) Total non-interest expense (29,919 ) (2,632 ) 1,852 (30,699 ) Income before income taxes 47,965 73 — 48,038 Income tax expense — (60 ) — (60 ) Net income $ 47,965 $ 13 $ — $ 47,978 August 31, 2018 CFC Other Elimination Consolidated Total Assets: Total loans outstanding $ 25,138,742 $ 1,139,507 $ (1,106,813 ) $ 25,171,436 Deferred loan origination costs 11,218 — — 11,218 Loans to members 25,149,960 1,139,507 (1,106,813 ) 25,182,654 Less: Allowance for loan losses (18,692 ) — — (18,692 ) Loans to members, net 25,131,268 1,139,507 (1,106,813 ) 25,163,962 Other assets 1,501,315 106,902 (95,972 ) 1,512,245 Total assets $ 26,632,583 $ 1,246,409 $ (1,202,785 ) $ 26,676,207

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Interest Income (Details) - USD ($) $ in Thousands		3 Months Ended
		Aug. 31, 2019	Aug. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest income		$ 290,015	$ 278,491
Investment Income, Interest		5,826	5,783
Long Term Fixed Rate Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest income	[1]	258,478	251,801
Long-term variable-rate loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest income		9,756	9,381
Line of credit loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest income		16,033	11,633
Restructured loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest income	[2]	206	218
Other Income
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest income	[3]	284	325
Loans Receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest income		$ 284,189	$ 272,708
[1]	Includes loan conversion fees, which are generally deferred and recognized as interest income using the effective interest method.
[2]	Troubled debt restructured (“TDR”) loans.
[3]	Consists of late payment fees, commitment fees and net amortization of deferred loan fees and loan origination costs.

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Interest Expense (Details) - USD ($) $ in Thousands		3 Months Ended
		Aug. 31, 2019	Aug. 31, 2018
Interest expense on debt:
Interest expense	[1],[2]	$ 213,271	$ 210,231
Short-term borrowings
Interest expense on debt:
Interest expense	[1],[2]	22,822	19,419
Medium-term notes
Interest expense on debt:
Interest expense	[1],[2]	32,076	32,410
Collateral trust bonds
Interest expense on debt:
Interest expense	[1],[2]	65,381	77,705
Guaranteed Underwriter Program notes payable
Interest expense on debt:
Interest expense	[1],[2]	40,433	35,334
Farmer Mac notes payable
Interest expense on debt:
Interest expense	[1],[2]	25,074	21,111
Other notes payable
Interest expense on debt:
Interest expense	[1],[2]	254	322
Subordinated deferrable debt
Interest expense on debt:
Interest expense	[1],[2]	12,882	9,417
Subordinated certificates
Interest expense on debt:
Interest expense	[1],[2]	$ 14,349	$ 14,513
[1]	Includes amortization of debt discounts and debt issuance costs, which are generally deferred and recognized as interest expense using the effective interest method. Issuance costs related to dealer commercial paper, however, are recognized as interest expense immediately as incurred.
[2]	Includes fees related to funding arrangements, such as up-front fees paid to banks participating in our committed bank revolving line of credit agreements. Depending on the nature of the fee, amounts may be deferred and recognized as interest expense ratably over the term of the arrangement or recognized immediately as incurred.

Summary of Significant Accoun_6

Summary of Significant Accounting Policies - Additional Information (Details) - USD ($)	3 Months Ended
	Aug. 31, 2019	Aug. 31, 2018	Jul. 22, 2019	May 31, 2019
Summary of Significant Accounting Policies [Line Items]
Repossessed Assets	$ 0			$ 0
Gain (Loss) on Sale of Properties	7,713,000	$ 0
Restricted Cash and Cash Equivalents	9,138,000			8,282,000
Deferred income	55,614,000			57,989,000
Deferred Loan Conversion Fees	50,000,000			$ 52,000,000
Land Available-for-sale			$ 14,000,000
Proceeds from sale of land	$ 21,618,000	$ 0

Variable Interest Entities - Co

Variable Interest Entities - Consolidated Assets and Liabilities of VIEs included in CFCs Condensed Consolidated Financial Statements (Details) - USD ($) $ in Thousands	Aug. 31, 2019	May 31, 2019	Aug. 31, 2018
Variable Interest Entity [Line Items]
Loans to members	$ 26,299,838	$ 25,916,904	$ 25,182,654
Other assets	46,576	53,699
Total assets	27,578,756	27,124,372	$ 26,676,207
Long-term debt	19,094,236	19,210,793
Other liabilities	48,462	50,112
Total liabilities	26,660,328	25,820,490
Variable Interest Entity, Primary Beneficiary, Aggregated Disclosure
Variable Interest Entity [Line Items]
Loans to members	1,048,892	1,087,988
Other assets	10,074	10,963
Total assets	1,058,966	1,098,951
Long-term debt	6,000	6,000
Other liabilities	36,878	33,385
Total liabilities	$ 42,878	$ 39,385

Variable Interest Entities - In

Variable Interest Entities - Information on CFCs Credit Commitments to NCSC and RTFC (Details) - USD ($) $ in Thousands		Aug. 31, 2019	May 31, 2019
Variable Interest Entity [Line Items]
CFC third-party guarantees		$ 801,327	$ 837,435
Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
CFC credit commitments		5,500,000	5,500,000
Borrowings payable to CFC	[1]	1,019,103	1,059,629
CFC third-party guarantees		11,339	10,091
Other credit enhancements		16,171	14,251
Total credit enhancements	[2]	27,510	24,342
CFC available credit commitments		1,046,613	1,083,971
CFC available credit commitments		$ 4,453,387	$ 4,416,029
[1]	Borrowings payable to CFC are eliminated in consolidation.
[2]	Excludes interest due on these instruments.

Variable Interest Entities - Ad

Variable Interest Entities - Additional Information (Details) $ in Millions	Aug. 31, 2019USD ($)
Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Maximum Potential Exposure Credit Enhancements	$ 29

Investment Securities - Amortiz

Investment Securities - Amortized cost and Fair Value of Equity Securities and Corresponding Gross Unrealized Gains and Losses (Details) - USD ($) $ in Thousands	Aug. 31, 2019	May 31, 2019
Debt and Equity Securities [Line Items]
Equity securities	$ 63,922	$ 87,533
Preferred Stock
Debt and Equity Securities [Line Items]
Equity securities	58,166	82,445
Common Stock
Debt and Equity Securities [Line Items]
Equity securities	$ 5,756	$ 5,088

Investment Securities - Debt Se

Investment Securities - Debt Securities and Corresponding Gross Unrealized Gains and Losses (Details) - USD ($) $ in Thousands	Aug. 31, 2019	May 31, 2019
Debt Securities, Held-to-maturity, Fair Value to Amortized Cost [Abstract]
Debt securities held-to-maturity, at amortized cost	$ 569,575	$ 565,444
Gross Unrealized Gains	11,128	6,072
Gross Unrealized Losses	(227)	(967)
Debt Securities, Held-to-maturity, Fair Value	580,476	570,549
Certificates of deposit
Debt Securities, Held-to-maturity, Fair Value to Amortized Cost [Abstract]
Debt securities held-to-maturity, at amortized cost	6,123	1,000
Gross Unrealized Gains	2	0
Gross Unrealized Losses	0	0
Debt Securities, Held-to-maturity, Fair Value	6,125	1,000
Commercial paper
Debt Securities, Held-to-maturity, Fair Value to Amortized Cost [Abstract]
Debt securities held-to-maturity, at amortized cost	5,950	12,395
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Debt Securities, Held-to-maturity, Fair Value	5,950	12,395
U.S. agency debt securities
Debt Securities, Held-to-maturity, Fair Value to Amortized Cost [Abstract]
Debt securities held-to-maturity, at amortized cost	4,563	3,207
Gross Unrealized Gains	201	108
Gross Unrealized Losses	0	0
Debt Securities, Held-to-maturity, Fair Value	4,764	3,315
Corporate debt securities
Debt Securities, Held-to-maturity, Fair Value to Amortized Cost [Abstract]
Debt securities held-to-maturity, at amortized cost	481,914	478,578
Gross Unrealized Gains	9,426	4,989
Gross Unrealized Losses	(219)	(912)
Debt Securities, Held-to-maturity, Fair Value	491,121	482,655
Agency
Debt Securities, Held-to-maturity, Fair Value to Amortized Cost [Abstract]
Debt securities held-to-maturity, at amortized cost	7,243	7,255
Gross Unrealized Gains	473	291
Gross Unrealized Losses	0	0
Debt Securities, Held-to-maturity, Fair Value	7,716	7,546
Non-agency
Debt Securities, Held-to-maturity, Fair Value to Amortized Cost [Abstract]
Debt securities held-to-maturity, at amortized cost	3,453	3,453
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(5)	(7)
Debt Securities, Held-to-maturity, Fair Value	3,448	3,446
Total commercial MBS
Debt Securities, Held-to-maturity, Fair Value to Amortized Cost [Abstract]
Debt securities held-to-maturity, at amortized cost	10,696	10,708
Gross Unrealized Gains	473	291
Gross Unrealized Losses	(5)	(7)
Debt Securities, Held-to-maturity, Fair Value	11,164	10,992
U.S. state and municipality debt securities
Debt Securities, Held-to-maturity, Fair Value to Amortized Cost [Abstract]
Debt securities held-to-maturity, at amortized cost	9,606	9,608
Gross Unrealized Gains	520	352
Gross Unrealized Losses	0	0
Debt Securities, Held-to-maturity, Fair Value	10,126	9,960
Foreign government debt securities
Debt Securities, Held-to-maturity, Fair Value to Amortized Cost [Abstract]
Debt securities held-to-maturity, at amortized cost	1,257	1,254
Gross Unrealized Gains	58	42
Gross Unrealized Losses	0	0
Debt Securities, Held-to-maturity, Fair Value	1,315	1,296
Other ABS
Debt Securities, Held-to-maturity, Fair Value to Amortized Cost [Abstract]
Debt securities held-to-maturity, at amortized cost	49,466	48,694
Gross Unrealized Gains	448	290
Gross Unrealized Losses	(3)	(48)
Debt Securities, Held-to-maturity, Fair Value	$ 49,911	$ 48,936

Investment Securities - Fair Va

Investment Securities - Fair Value and Gross Unrealized Losses for Investments in a Gross Loss Position (Details) - USD ($)		Aug. 31, 2019	May 31, 2019
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position [Abstract]
Less than 12 months, Fair value, held-to-maturity		$ 54,342,000	$ 52,665,000
Less than 12 months, Gross unrealized losses, held-to-maturity		(80,000)	(206,000)
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value		53,559,000	179,374,000
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss		(147,000)	(761,000)
Total Fair Value		107,901,000	232,039,000
Gross Unrealized Losses		(227,000)	(967,000)
Commercial paper
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position [Abstract]
Less than 12 months, Fair value, held-to-maturity	[1]		2,688,000
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value			1,000
Total Fair Value	[1]		2,688,000
Corporate debt securities
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position [Abstract]
Less than 12 months, Fair value, held-to-maturity		50,895,000	45,999,000
Less than 12 months, Gross unrealized losses, held-to-maturity		(75,000)	(198,000)
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value		45,650,000	164,086,000
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss		(144,000)	(714,000)
Total Fair Value		96,545,000	210,085,000
Gross Unrealized Losses		(219,000)	(912,000)
Non-agency
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position [Abstract]
Less than 12 months, Fair value, held-to-maturity		3,447,000	1,996,000
Less than 12 months, Gross unrealized losses, held-to-maturity		(5,000)	(4,000)
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value			1,448,000
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss			(3,000)
Total Fair Value		3,447,000	3,444,000
Gross Unrealized Losses		(5,000)	(7,000)
Other ABS
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position [Abstract]
Less than 12 months, Fair value, held-to-maturity	[2]	0	1,982,000
Less than 12 months, Gross unrealized losses, held-to-maturity	[2]	0	(4,000)
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	[2]	7,909,000	13,840,000
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	[2]	(3,000)	(44,000)
Total Fair Value	[2]	7,909,000	15,822,000
Gross Unrealized Losses	[2]	$ (3,000)	$ (48,000)
[1]	Unrealized losses on the commercial paper investments are less than $1,000.
[2]	Consists primarily of securities backed by auto lease loans, equipment-backed loans, auto loans and credit card loans.

Investment Securities - Remaini

Investment Securities - Remaining Contractual Maturity Based on Amortized Cost and Fair Value of HTM by Type (Details) - USD ($) $ in Thousands	Aug. 31, 2019	May 31, 2019
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost, Rolling Maturity [Abstract]
Due in 1 Year or Less	$ 72,839	$ 64,828
Due 1 Year through 5 Years	474,126	475,368
Due 5 Years through 10 Years	19,157	21,795
Due 10 Years	3,453	3,453
Debt securities held-to-maturity, at amortized cost	569,575	565,444
Debt Securities, Held-to-maturity, Maturity, Fair Value, Rolling Maturity [Abstract]
Due in 1 Year or Less	72,859	64,722
Due 1 Year through 5 Years	484,028	479,864
Due 5 Years through 10 Years	20,141	22,517
Due 10 Years	3,448	3,446
Debt Securities, Held-to-maturity, Fair Value	$ 580,476	$ 570,549
Due in 1 Year or Less	2.32%	2.08%
Due 1 Year through 5 Years	3.03%	3.10%
Due 5 Years through 10 Years	3.00%	3.07%
Due 10 Years	3.02%	3.26%
Held To Maturity Securities Expected Debt Maturities Weighted Average Yield	2.94%	2.98%
Certificates of deposit
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost, Rolling Maturity [Abstract]
Due in 1 Year or Less	$ 5,123	$ 0
Due 1 Year through 5 Years	1,000	1,000
Due 5 Years through 10 Years	0
Due 10 Years	0
Debt securities held-to-maturity, at amortized cost	6,123	1,000
Debt Securities, Held-to-maturity, Maturity, Fair Value, Rolling Maturity [Abstract]
Due in 1 Year or Less	5,125	0
Due 1 Year through 5 Years	1,000	1,000
Due 5 Years through 10 Years	0
Due 10 Years	0
Debt Securities, Held-to-maturity, Fair Value	6,125	1,000
Commercial paper
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost, Rolling Maturity [Abstract]
Due in 1 Year or Less	5,950	12,395
Due 1 Year through 5 Years	0
Due 5 Years through 10 Years	0
Due 10 Years	0
Debt securities held-to-maturity, at amortized cost	5,950	12,395
Debt Securities, Held-to-maturity, Maturity, Fair Value, Rolling Maturity [Abstract]
Due in 1 Year or Less	5,950	12,395
Due 1 Year through 5 Years	0
Due 5 Years through 10 Years	0
Due 10 Years	0
Debt Securities, Held-to-maturity, Fair Value	5,950	12,395
U.S. agency debt securities
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost, Rolling Maturity [Abstract]
Due 1 Year through 5 Years	2,682	2,678
Due 5 Years through 10 Years	1,881	529
Debt securities held-to-maturity, at amortized cost	4,563	3,207
Debt Securities, Held-to-maturity, Maturity, Fair Value, Rolling Maturity [Abstract]
Due in 1 Year or Less	0
Due 1 Year through 5 Years	2,811	2,769
Due 5 Years through 10 Years	1,953	546
Due 10 Years	0
Debt Securities, Held-to-maturity, Fair Value	4,764	3,315
Corporate debt securities
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost, Rolling Maturity [Abstract]
Due in 1 Year or Less	61,766	51,923
Due 1 Year through 5 Years	408,037	414,788
Due 5 Years through 10 Years	12,111	11,867
Due 10 Years	0
Debt securities held-to-maturity, at amortized cost	481,914	478,578
Debt Securities, Held-to-maturity, Maturity, Fair Value, Rolling Maturity [Abstract]
Due in 1 Year or Less	61,784	51,818
Due 1 Year through 5 Years	416,655	418,606
Due 5 Years through 10 Years	12,682	12,231
Due 10 Years	0
Debt Securities, Held-to-maturity, Fair Value	491,121	482,655
Agency
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost, Rolling Maturity [Abstract]
Due 1 Year through 5 Years	2,078	310
Due 5 Years through 10 Years	5,165	6,945
Due 10 Years	0
Debt securities held-to-maturity, at amortized cost	7,243	7,255
Debt Securities, Held-to-maturity, Maturity, Fair Value, Rolling Maturity [Abstract]
Due in 1 Year or Less	0
Due 1 Year through 5 Years	2,210	317
Due 5 Years through 10 Years	5,506	7,229
Due 10 Years	0
Debt Securities, Held-to-maturity, Fair Value	7,716	7,546
Non-agency
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost, Rolling Maturity [Abstract]
Due 1 Year through 5 Years	0
Due 5 Years through 10 Years	0
Due 10 Years	3,453	3,453
Debt securities held-to-maturity, at amortized cost	3,453	3,453
Debt Securities, Held-to-maturity, Maturity, Fair Value, Rolling Maturity [Abstract]
Due in 1 Year or Less	0
Due 1 Year through 5 Years	0
Due 5 Years through 10 Years	0
Due 10 Years	3,448	3,446
Debt Securities, Held-to-maturity, Fair Value	3,448	3,446
Total commercial MBS
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost, Rolling Maturity [Abstract]
Due 1 Year through 5 Years	2,078	310
Due 5 Years through 10 Years	5,165	6,945
Due 10 Years	3,453	3,453
Debt securities held-to-maturity, at amortized cost	10,696	10,708
Debt Securities, Held-to-maturity, Maturity, Fair Value, Rolling Maturity [Abstract]
Due in 1 Year or Less	0
Due 1 Year through 5 Years	2,210	317
Due 5 Years through 10 Years	5,506	7,229
Due 10 Years	3,448	3,446
Debt Securities, Held-to-maturity, Fair Value	11,164	10,992
U.S. state and municipality debt securities
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost, Rolling Maturity [Abstract]
Due 1 Year through 5 Years	9,606	9,608
Due 5 Years through 10 Years	0	0
Due 10 Years	0
Debt securities held-to-maturity, at amortized cost	9,606	9,608
Debt Securities, Held-to-maturity, Maturity, Fair Value, Rolling Maturity [Abstract]
Due in 1 Year or Less	0
Due 1 Year through 5 Years	10,126	9,960
Due 5 Years through 10 Years	0	0
Due 10 Years	0
Debt Securities, Held-to-maturity, Fair Value	10,126	9,960
Foreign government debt securities
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost, Rolling Maturity [Abstract]
Due 1 Year through 5 Years	1,257	1,254
Due 5 Years through 10 Years	0
Due 10 Years	0
Debt securities held-to-maturity, at amortized cost	1,257	1,254
Debt Securities, Held-to-maturity, Maturity, Fair Value, Rolling Maturity [Abstract]
Due in 1 Year or Less	0
Due 1 Year through 5 Years	1,315	1,296
Due 5 Years through 10 Years	0
Due 10 Years	0
Debt Securities, Held-to-maturity, Fair Value	1,315	1,296
Other ABS
Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost, Rolling Maturity [Abstract]
Due in 1 Year or Less	0	510
Due 1 Year through 5 Years	49,466	45,730
Due 5 Years through 10 Years	0	2,454
Due 10 Years	0
Debt securities held-to-maturity, at amortized cost	49,466	48,694
Debt Securities, Held-to-maturity, Maturity, Fair Value, Rolling Maturity [Abstract]
Due in 1 Year or Less	0	509
Due 1 Year through 5 Years	49,911	45,916
Due 5 Years through 10 Years	0	2,511
Due 10 Years	0
Debt Securities, Held-to-maturity, Fair Value	$ 49,911	$ 48,936

Investment Securities - Additio

Investment Securities - Additional Information (Details) - USD ($)	3 Months Ended
	Aug. 31, 2019	Aug. 31, 2018	Jun. 12, 2019	May 31, 2019
Debt and Equity Securities [Line Items]
Equity Securities Unrealized Gain	$ 2,000,000
Equity Securities Unrealized Loss		$ 1,000,000
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	$ 53,559,000			$ 179,374,000
Preferred Stock, Redemption Price Per Share			$ 25
Investment Securities in Unrealized Loss Positions, Number of Positions	84
Average Contractual Maturity of Held-to-maturity Securities	3 years
Held To Maturity Securities Expected Debt Maturities Weighted Average Yield	2.94%			2.98%
Equity Securities, FV-NI, Realized Gain (Loss)	$ 200,000
Gain (Loss) on Sale of Debt Investments	$ 0	$ 0
Preferred Stock
Debt and Equity Securities [Line Items]
Equity Securities, FV-NI, Cost			$ 25,000,000

Loans - Outstanding Principal B

Loans - Outstanding Principal Balance and Unadvanced Commitments (Details) - USD ($) $ in Thousands		Aug. 31, 2019	May 31, 2019		Aug. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total recorded investment in loans		$ 26,288,599	$ 25,905,664		$ 25,171,436
Unamortized Loan Commitment and Origination Fees and Unamortized Discounts or Premiums		11,239	11,240		11,218
Loans to members		26,299,838	25,916,904		$ 25,182,654
Unadvanced commitments
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unadvanced commitments	[1]	13,053,743	13,237,558
CFC
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total recorded investment in loans		25,239,707	24,817,676
CFC | Unadvanced commitments
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unadvanced commitments	[1]	12,193,718	12,405,385
CFC | Distribution
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total recorded investment in loans		20,484,460	20,155,266
CFC | Distribution | Unadvanced commitments
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unadvanced commitments	[1]	8,568,888	8,773,018
CFC | Power supply
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total recorded investment in loans		4,671,035	4,578,841
CFC | Power supply | Unadvanced commitments
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unadvanced commitments	[1]	3,456,266	3,466,680
CFC | Statewide and associate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total recorded investment in loans		84,212	83,569
CFC | Statewide and associate | Unadvanced commitments
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unadvanced commitments	[1]	168,564	165,687
NCSC
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total recorded investment in loans		697,791	742,888
NCSC | Unadvanced commitments
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unadvanced commitments	[1]	575,888	552,840
RTFC
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total recorded investment in loans		351,101	345,100
RTFC | Unadvanced commitments
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unadvanced commitments	[1]	284,137	279,333
Long Term Fixed Rate Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total recorded investment in loans		23,677,234	23,094,253
Long-term variable-rate loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total recorded investment in loans		962,541	1,066,880
Long-term variable-rate loans | Unadvanced commitments
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unadvanced commitments	[1]	5,140,530	5,448,636
Long Term Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total recorded investment in loans		24,639,775	24,161,133
Long Term Loans | Unadvanced commitments
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unadvanced commitments	[1]	5,140,530	5,448,636
Line of credit loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total recorded investment in loans		1,648,824	1,744,531
Line of credit loans | Unadvanced commitments
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unadvanced commitments		$ 7,913,213	$ 7,788,922	[1]
[1]	The interest rate on unadvanced loan commitments is not set until an advance is made; therefore, all long-term unadvanced loan commitments are reported as variable-rate. However, the borrower may select either a fixed or a variable rate when an advance on a commitment is made.

Loans - Available Balance Under

Loans - Available Balance Under Unadvanced Commitments and Maturity (Details) - Unadvanced commitments - USD ($) $ in Thousands		Aug. 31, 2019	May 31, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Available Balance	[1]	$ 13,053,743	$ 13,237,558
2020		915,666
2021		4,793,927
2022		1,780,751
2023		2,445,125
2024		2,690,604
Thereafter		427,670
Line of credit loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Available Balance		7,913,213	7,788,922	[1]
2020		609,206
2021		4,128,566
2022		485,285
2023		1,364,426
2024		1,055,813
Thereafter		269,917
Long-term variable-rate loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Available Balance	[1]	5,140,530	$ 5,448,636
2020		306,460
2021		665,361
2022		1,295,466
2023		1,080,699
2024		1,634,791
Thereafter		$ 157,753
[1]	The interest rate on unadvanced loan commitments is not set until an advance is made; therefore, all long-term unadvanced loan commitments are reported as variable-rate. However, the borrower may select either a fixed or a variable rate when an advance on a commitment is made.

Loans - Unconditional Committed

Loans - Unconditional Committed Lines of Credit and Maturity (Details) - USD ($) $ in Thousands		Aug. 31, 2019	May 31, 2019
Unadvanced commitments
Notional maturities of committed lines of credit
Available Balance	[1]	$ 13,053,743	$ 13,237,558
2020		915,666
2021		4,793,927
2022		1,780,751
2023		2,445,125
2024		2,690,604
Thereafter		427,670
Unadvanced commitments not subject to material adverse change clauses
Notional maturities of committed lines of credit
Available Balance		3,003,647	$ 2,944,000
2020		260,886
2021		478,489
2022		171,875
2023		1,166,687
2024		811,510
Thereafter		$ 114,200
[1]	The interest rate on unadvanced loan commitments is not set until an advance is made; therefore, all long-term unadvanced loan commitments are reported as variable-rate. However, the borrower may select either a fixed or a variable rate when an advance on a commitment is made.

Loans - Outstanding Pledged as

Loans - Outstanding Pledged as Collateral (Details) - USD ($) $ in Thousands	Aug. 31, 2019	May 31, 2019
Pledging of Loans and Loans on Deposit
Restricted Cash and Cash Equivalents	$ 9,138	$ 8,282
Collateral trust bonds 2007 indenture
Pledging of Loans and Loans on Deposit
Loans outstanding and pledged as collateral	8,690,428	8,909,909
Secured Debt	7,622,711	7,622,711
Collateral trust bonds 1994 indenture
Pledging of Loans and Loans on Deposit
Secured Debt	40,000	40,000
Notes payable | Federal Agricultural Mortgage Corporation
Pledging of Loans and Loans on Deposit
Secured Debt	2,962,478	3,054,914
Clean Renewable Energy Bonds Series 2009A
Pledging of Loans and Loans on Deposit
Restricted Cash and Cash Equivalents	802	415
Secured Debt	9,225	9,225
Assets Pledged as Collateral	10,601	10,764
Guaranteed Underwriter Program notes payable
Pledging of Loans and Loans on Deposit
Secured Debt	5,387,155	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	8,557,299	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	46,522	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	3,760,219	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	9,799	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	133,129	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	$ 6,127,684	$ 6,157,218

Loans - Internal Risk Rating (D

Loans - Internal Risk Rating (Details) - USD ($) $ in Thousands	Aug. 31, 2019	May 31, 2019	Aug. 31, 2018
Credit Quality
Total recorded investment in loans	$ 26,288,599	$ 25,905,664	$ 25,171,436
CFC
Credit Quality
Total recorded investment in loans	25,239,707	24,817,676
CFC | Distribution
Credit Quality
Total recorded investment in loans	20,484,460	20,155,266
CFC | Power supply
Credit Quality
Total recorded investment in loans	4,671,035	4,578,841
CFC | Statewide and associate
Credit Quality
Total recorded investment in loans	84,212	83,569
NCSC
Credit Quality
Total recorded investment in loans	697,791	742,888
RTFC
Credit Quality
Total recorded investment in loans	351,101	345,100
Pass
Credit Quality
Total recorded investment in loans	26,090,422	25,703,866
Pass | CFC
Credit Quality
Total recorded investment in loans	25,046,997	24,621,470
Pass | CFC | Distribution
Credit Quality
Total recorded investment in loans	20,354,654	20,022,193
Pass | CFC | Power supply
Credit Quality
Total recorded investment in loans	4,623,131	4,530,708
Pass | CFC | Statewide and associate
Credit Quality
Total recorded investment in loans	69,212	68,569
Pass | NCSC
Credit Quality
Total recorded investment in loans	697,791	742,888
Pass | RTFC
Credit Quality
Total recorded investment in loans	345,634	339,508
Special Mention
Credit Quality
Total recorded investment in loans	23,222	25,375
Special Mention | CFC
Credit Quality
Total recorded investment in loans	23,222	25,375
Special Mention | CFC | Distribution
Credit Quality
Total recorded investment in loans	8,222	10,375
Special Mention | CFC | Statewide and associate
Credit Quality
Total recorded investment in loans	15,000	15,000
Special Mention | NCSC
Credit Quality
Total recorded investment in loans	0
Special Mention | RTFC
Credit Quality
Total recorded investment in loans	0	0
Substandard
Credit Quality
Total recorded investment in loans	174,955	176,423
Substandard | CFC
Credit Quality
Total recorded investment in loans	169,488	170,831
Substandard | CFC | Distribution
Credit Quality
Total recorded investment in loans	121,584	122,698
Substandard | CFC | Power supply
Credit Quality
Total recorded investment in loans	47,904	48,133
Substandard | RTFC
Credit Quality
Total recorded investment in loans	$ 5,467	$ 5,592

Loans - Payment Status of Loans

Loans - Payment Status of Loans Outstanding (Details) - USD ($) $ in Thousands		Aug. 31, 2019	May 31, 2019	Aug. 31, 2018
Payment Status of Loans
Past due		$ 0	$ 0
Total recorded investment in loans		26,288,599	25,905,664	$ 25,171,436
Non-accrual loans		$ 0	$ 0
As a % of total loans
Current (percent)		100.00%	100.00%
30-89 days past due (percent)		0.00%	0.00%
90 days or more past due (percent)	[1]	0.00%	0.00%
Total past due (percent)		0.00%	0.00%
Total financing receivables (percent)		100.00%	100.00%
Non-accrual loans (percent)		0.00%	0.00%
CFC
Payment Status of Loans
Past due		$ 0	$ 0
Total recorded investment in loans		25,239,707	24,817,676
Non-accrual loans		0	0
CFC | Distribution
Payment Status of Loans
Past due		0	0
Total recorded investment in loans		20,484,460	20,155,266
Non-accrual loans		0	0
CFC | Power supply
Payment Status of Loans
Past due		0	0
Total recorded investment in loans		4,671,035	4,578,841
Non-accrual loans		0	0
CFC | Statewide and associate
Payment Status of Loans
Total recorded investment in loans		84,212	83,569
NCSC
Payment Status of Loans
Past due		0	0
Total recorded investment in loans		697,791	742,888
Non-accrual loans		0	0
RTFC
Payment Status of Loans
Past due		0
Total recorded investment in loans		351,101	345,100
Non-accrual loans		0	0
Financial Asset, 1 to 29 Days Past Due [Member]
Payment Status of Loans
Current		26,288,599	25,905,664
Financial Asset, 1 to 29 Days Past Due [Member] | CFC
Payment Status of Loans
Current		25,239,707	24,817,676
Financial Asset, 1 to 29 Days Past Due [Member] | CFC | Distribution
Payment Status of Loans
Current		20,484,460	20,155,266
Financial Asset, 1 to 29 Days Past Due [Member] | CFC | Power supply
Payment Status of Loans
Current		4,671,035	4,578,841
Financial Asset, 1 to 29 Days Past Due [Member] | CFC | Statewide and associate
Payment Status of Loans
Current		84,212	83,569
Financial Asset, 1 to 29 Days Past Due [Member] | NCSC
Payment Status of Loans
Current		697,791	742,888
Financial Asset, 1 to 29 Days Past Due [Member] | RTFC
Payment Status of Loans
Current		351,101	345,100
Financing Receivables, 30 to 89 Days Past Due [Member]
Payment Status of Loans
Past due		0	0
Financing Receivables, 30 to 89 Days Past Due [Member] | CFC
Payment Status of Loans
Past due		0	0
Financing Receivables, 30 to 89 Days Past Due [Member] | CFC | Distribution
Payment Status of Loans
Past due		0	0
Financing Receivables, 30 to 89 Days Past Due [Member] | CFC | Power supply
Payment Status of Loans
Past due		0	0
Financing Receivables, 30 to 89 Days Past Due [Member] | NCSC
Payment Status of Loans
Past due		0	0
Financing Receivables, 30 to 89 Days Past Due [Member] | RTFC
Payment Status of Loans
Past due		0	0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Payment Status of Loans
Past due	[1]	0	0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | CFC
Payment Status of Loans
Past due	[1]	0	0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | CFC | Distribution
Payment Status of Loans
Past due	[1]	0	0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | CFC | Power supply
Payment Status of Loans
Past due	[1]	0	0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | NCSC
Payment Status of Loans
Past due	[1]	$ 0	$ 0
[1]	All loans 90 days or more past due are on nonaccrual status.

Loans - Troubled Debt Restructu

Loans - Troubled Debt Restructured Loans (Details) - USD ($) $ in Thousands	Aug. 31, 2019	May 31, 2019	Aug. 31, 2018
Financing Receivable, Troubled Debt Restructuring [Line Items]
Total recorded investment in loans	$ 26,288,599	$ 25,905,664	$ 25,171,436
Loans and Leases Receivable Commercial, Net of Deferred Income, Percentage	100.00%	100.00%
Performing TDR loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans outstanding	$ 11,222	$ 11,853
Performing TDR Loans As Percentage of Total Loans	0.04%	0.05%
Total TDR loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Total recorded investment in loans	$ 11,222	$ 11,853
Loans and Leases Receivable Commercial, Net of Deferred Income, Percentage	0.04%	0.05%
CFC
Financing Receivable, Troubled Debt Restructuring [Line Items]
Total recorded investment in loans	$ 25,239,707	$ 24,817,676
CFC | Performing TDR loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans outstanding	$ 5,755	$ 6,261
Performing TDR Loans As Percentage of Total Loans	0.02%	0.03%
RTFC
Financing Receivable, Troubled Debt Restructuring [Line Items]
Total recorded investment in loans	$ 351,101	$ 345,100
RTFC | Performing TDR loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans outstanding	$ 5,467	$ 5,592
Performing TDR Loans As Percentage of Total Loans	0.02%	0.02%

Loans Impaired Loans - Recorded

Loans Impaired Loans - Recorded Investment and Allowance (Details) - USD ($) $ in Thousands	Aug. 31, 2019	May 31, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]
Impaired Financing Receivable, Related Allowance	$ 989	$ 1,021
Impaired Financing Receivable, Recorded Investment	11,222	11,853
CFC
Accounts, Notes, Loans and Financing Receivable [Line Items]
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	5,755	6,261
RTFC
Accounts, Notes, Loans and Financing Receivable [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment	5,467	5,592
Impaired Financing Receivable, Related Allowance	$ 989	$ 1,021

Impaired Loans - Average Record

Impaired Loans - Average Recorded Investment and Interest Income (Details) - USD ($) $ in Thousands	3 Months Ended
	Aug. 31, 2019	Aug. 31, 2018
Average recorded investment
Total impaired loans	$ 11,786	$ 12,552
Interest income recognized
Interest impaired loans	206	218
CFC
Average recorded investment
Total impaired loans	6,239	6,504
Interest income recognized
Interest impaired loans	137	142
RTFC
Average recorded investment
Total impaired loans	5,547	6,048
Interest income recognized
Interest impaired loans	$ 69	$ 76

Loans - Additional Information

Loans - Additional Information (Details)		3 Months Ended		12 Months Ended
		Aug. 31, 2019USD ($)memberpower_supply_systemdistribution_systemborrowerassociate	Aug. 31, 2018USD ($)	May 31, 2019USD ($)power_supply_systemdistribution_systemborrowerassociate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Line of Credit Commitments as percentage of unadvanced loan commitment		61.00%
Long-term Loan commitments as percentage of unadvanced loan commitment		39.00%
Loans Receivable Cost of Loans Sold		$ 20,000,000
Number of Borrowers | member		900
Number of States in which Electric and Telecommunications Borrowers are Located		49
Total recorded investment in loans		$ 26,288,599,000	$ 25,171,436,000	$ 25,905,664,000
Number of Borrowers With TDR Loans		1		1
Financing Receivable, Troubled Debt Restructuring, Subsequent Default		$ 0	0
Accounts Receivable, Allowance for Credit Loss, Writeoff		0	0
Nonperforming TDR loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment		0		$ 0
Loans and Leases Receivable, Impaired, Interest Lost on Nonaccrual Loans		0	$ 0
Performing line of credit for Troubled Debt Restructuring Borrower [Member] | Line of Credit to Provide Bridge Funding
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unadvanced commitments		2,000,000		2,000,000
Total recorded investment in loans		1,000,000		1,000,000
Performing line of credit for Troubled Debt Restructuring Borrower [Member] | Line of Credit Restricted for Fuel Purchases
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unadvanced commitments		6,000,000		6,000,000
Total recorded investment in loans		1,000,000		3,000,000
Nonperforming Financial Instruments
Accounts, Notes, Loans and Financing Receivable [Line Items]
Impaired Financing Receivable, with Related Allowance, Recorded Investment		0		0
Substandard
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total recorded investment in loans		174,955,000		176,423,000
CFC
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total recorded investment in loans		25,239,707,000		24,817,676,000
CFC | Distribution
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total recorded investment in loans		20,484,460,000		20,155,266,000
CFC | Power supply
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total recorded investment in loans		4,671,035,000		4,578,841,000
CFC | Substandard
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total recorded investment in loans		169,488,000		170,831,000
CFC | Substandard | Distribution
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total recorded investment in loans		121,584,000		122,698,000
CFC | Substandard | Power supply
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total recorded investment in loans		47,904,000		48,133,000
Unadvanced commitments
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unadvanced commitments	[1]	13,053,743,000		13,237,558,000
Unadvanced commitments | CFC
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unadvanced commitments	[1]	12,193,718,000		12,405,385,000
Unadvanced commitments | CFC | Distribution
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unadvanced commitments	[1]	8,568,888,000		8,773,018,000
Unadvanced commitments | CFC | Power supply
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unadvanced commitments	[1]	3,456,266,000		3,466,680,000
Unadvanced commitments not subject to material adverse change clauses
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unadvanced commitments		3,003,647,000		2,944,000,000
Commitments to Extend Credit Subject to Material Adverse Change Clause
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unadvanced commitments		10,050,000,000		10,294,000,000
Long-term variable-rate loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total recorded investment in loans		962,541,000		1,066,880,000
Long-term variable-rate loans | Unadvanced commitments
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unadvanced commitments	[1]	$ 5,140,530,000		$ 5,448,636,000
Loans Receivable Commercial and Industrial | Credit Concentration Risk
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration Risk, Percentage		2.00%		2.00%
Concentration Risk Number of Borrowers | borrower		20		20
Loans Receivable Commercial and Industrial | Credit Concentration Risk | Distribution
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration Risk Number of Borrowers | distribution_system		10		10
Loans Receivable Commercial and Industrial | Credit Concentration Risk | Power supply
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration Risk Number of Borrowers | power_supply_system		9		9
Loans Receivable Commercial and Industrial | Credit Concentration Risk | Associates
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration Risk Number of Borrowers | associate		1		1
Loans Receivable Commercial and Industrial | Customer Concentration Risk
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration Risk, Percentage		22.00%		22.00%
Loans Receivable Commercial and Industrial | Geographic Concentration Risk
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration Risk, Percentage		16.00%		15.00%
Loans Receivable Commercial and Industrial | Product Concentration Risk
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration Risk, Percentage		99.00%		99.00%
Loans Guaranteed by Farmer Mac
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total recorded investment in loans		$ 602,000,000		$ 619,000,000
Loans Guaranteed by Rural Utilities Service
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total recorded investment in loans		$ 152,000,000		$ 154,000,000
[1]	The interest rate on unadvanced loan commitments is not set until an advance is made; therefore, all long-term unadvanced loan commitments are reported as variable-rate. However, the borrower may select either a fixed or a variable rate when an advance on a commitment is made.

Allowance for Loan Losses - Ro

Allowance for Loan Losses - Rollforward (Details) - USD ($) $ in Thousands	3 Months Ended
	Aug. 31, 2019	Aug. 31, 2018	May 31, 2019	May 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total ending balance of the allowance	$ 17,565	$ 18,692	$ 17,535	$ 18,801
Provision for Loan and Lease Losses	30	109
CFC
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total ending balance of the allowance	12,962	12,508	13,120	12,300
Provision for Loan and Lease Losses	158	208
NCSC
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total ending balance of the allowance	2,077	2,012	2,007	2,082
Provision for Loan and Lease Losses	(70)	70
RTFC
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total ending balance of the allowance	2,526	4,172	$ 2,408	$ 4,419
Provision for Loan and Lease Losses	$ 118	$ (247)

Allowance for Loan Losses - Re

Allowance for Loan Losses - Recorded Investments (Details) - USD ($) number in Thousands, $ in Thousands	Aug. 31, 2019	May 31, 2019	Aug. 31, 2018	May 31, 2018
Ending balance of the allowance:
Collectively evaluated loans	$ 16,576	$ 16,514
Specific allowance	989	1,021
Total ending balance of the allowance	17,565	17,535	$ 18,692	$ 18,801
Recorded investment in loans:
Collectively evaluated loans	26,277,377	25,893,811
Individually evaluated loans	11,222	11,853
Total recorded investment in loans	26,288,599	25,905,664	25,171,436
Loans and Leases Receivable, Net Amount	$ 26,271,034	$ 25,888,129
Allowance Coverage Ratio	0.00%	0.00%
Unamortized Loan Commitment and Origination Fees and Unamortized Discounts or Premiums	$ 11,239	$ 11,240	11,218
CFC
Ending balance of the allowance:
Collectively evaluated loans	12,962	13,120
Specific allowance		0
Total ending balance of the allowance	12,962	13,120	12,508	12,300
Recorded investment in loans:
Collectively evaluated loans	25,233,952	24,811,415
Individually evaluated loans	5,755	6,261
Total recorded investment in loans	25,239,707	24,817,676
Loans and Leases Receivable, Net Amount	$ 25,226,745	$ 24,804,556
Allowance Coverage Ratio	0.00%	0.00%
NCSC
Ending balance of the allowance:
Collectively evaluated loans	$ 2,077	$ 2,007
Specific allowance	0	0
Total ending balance of the allowance	2,077	2,007	2,012	2,082
Recorded investment in loans:
Collectively evaluated loans	697,791	742,888
Individually evaluated loans	0	0
Total recorded investment in loans	697,791	742,888
Loans and Leases Receivable, Net Amount	$ 695,714	$ 740,881
Allowance Coverage Ratio	0.00%	0.00%
RTFC
Ending balance of the allowance:
Collectively evaluated loans	$ 1,537	$ 1,387
Specific allowance	989	1,021
Total ending balance of the allowance	2,526	2,408	$ 4,172	$ 4,419
Recorded investment in loans:
Collectively evaluated loans	345,634	339,508
Individually evaluated loans	5,467	5,592
Total recorded investment in loans	351,101	345,100
Loans and Leases Receivable, Net Amount	$ 348,575	$ 342,692
Allowance Coverage Ratio	0.00%	0.00%

Allowance for Loan Losses - Ad

Allowance for Loan Losses - Additional Information (Details) - USD ($) $ in Millions	Aug. 31, 2019	May 31, 2019
Receivables [Abstract]
Credit reserve for unadvanced loan commitments	$ 1	$ 1

Short-Term Borrowings - Additio

Short-Term Borrowings - Additional Information (Details) - USD ($)	Aug. 31, 2019	May 31, 2019
Short-term Debt [Line Items]
Short-term borrowings	$ 4,027,645,000	$ 3,607,726,000
Short Term Debt as Percentage of Debt Outstanding	16.00%	14.00%
Revolving credit agreements
Short-term Debt [Line Items]
Short-term borrowings	$ 0	$ 0
Maximum borrowing capacity	2,975,000,000	$ 2,975,000,000
Letter of Credit Maximum Amount Available	$ 300,000,000

Short-Term Borrowings - Outsta

Short-Term Borrowings - Outstanding (Details) - USD ($) $ in Thousands	Aug. 31, 2019	May 31, 2019
Short-term Debt [Line Items]
Short-term borrowings	$ 4,027,645	$ 3,607,726
Commercial paper sold through dealers, net of discounts
Short-term Debt [Line Items]
Short-term borrowings	829,763	944,616
Commercial paper sold directly to members, at par
Short-term Debt [Line Items]
Short-term borrowings	1,240,830	1,111,795
Commercial paper
Short-term Debt [Line Items]
Short-term borrowings	2,070,593	2,056,411
Select notes to members
Short-term Debt [Line Items]
Short-term borrowings	1,277,927	1,023,952
Daily liquidity fund notes to members
Short-term Debt [Line Items]
Short-term borrowings	435,070	298,817
Medium-term notes sold to members
Short-term Debt [Line Items]
Short-term borrowings	$ 244,055	$ 228,546

Short-Term Borrowings - Commitm

Short-Term Borrowings - Commitments under Revolving Credit Agreements (Details) - Revolving credit agreements - USD ($) $ in Thousands		3 Months Ended	12 Months Ended
		Aug. 31, 2019	May 31, 2019
Revolving Credit Agreements
Maximum borrowing capacity		$ 2,975,000	$ 2,975,000
Letters of credit outstanding		3,000	3,000
Total available		2,972,000	2,972,000
Three Year Agreement
Revolving Credit Agreements
Maximum borrowing capacity		1,440,000	1,440,000
Total available		$ 1,440,000	$ 1,440,000
Debt Instrument, Maturity Date		Nov. 28, 2021	Nov. 28, 2021
Line of Credit Facility Commitment Fee Percentage (percent)	[1]	0.075%	0.075%
Five Year Agreement
Revolving Credit Agreements
Maximum borrowing capacity		$ 1,535,000	$ 1,535,000
Letters of credit outstanding		3,238	3,000
Total available		$ 1,532,000	$ 1,532,000
Debt Instrument, Maturity Date		Nov. 28, 2023	Nov. 28, 2023
Line of Credit Facility Commitment Fee Percentage (percent)	[1]	0.10%	0.10%
[1]	Facility fee determined by CFC’s senior unsecured credit ratings based on the pricing schedules put in place at the inception of the related agreement.

Long-Term Debt Outstanding (Det

Long-Term Debt Outstanding (Details) - USD ($) $ in Thousands	Aug. 31, 2019	May 31, 2019
Long-term debt
Long-term debt	$ 19,094,236	$ 19,210,793
Collateral trust bonds
Long-term debt
Long-term Debt, Gross	7,662,711	7,662,711
Unamortized discount	(242,123)	(244,643)
Debt issuance costs	(32,952)	(34,336)
Long-term debt	7,387,636	7,383,732
Guaranteed Underwriter Program notes payable
Long-term debt
Long-term debt	5,387,155	5,410,507
Farmer Mac notes payable
Long-term debt
Long-term Debt, Gross	2,962,478	3,054,914
Other Secured Notes Payable
Long-term debt
Long-term Debt, Gross	9,225	9,225
Debt issuance costs	(162)	(178)
Long-term debt	9,063	9,047
Notes payable
Long-term debt
Long-term debt	8,358,696	8,474,468
Secured Debt
Long-term debt
Long-term debt	15,746,332	15,858,200
Medium-term notes sold through dealers
Long-term debt
Long-term Debt, Gross	2,935,540	2,962,375
Medium-term notes sold to members
Long-term debt
Long-term Debt, Gross	418,208	397,080
Unsecured Medium Term Notes
Long-term debt
Long-term Debt, Gross	3,353,748	3,359,455
Unamortized discount	(848)	(931)
Debt issuance costs	(18,492)	(19,399)
Long-term debt	3,334,408	3,339,125
Other Unsecured Notes Payable
Long-term debt
Long-term Debt, Gross	13,701	13,701
Unamortized discount	(164)	(187)
Debt issuance costs	(41)	(46)
Unsecured notes payable
Long-term debt
Long-term debt	13,496	13,468
Unsecured Debt
Long-term debt
Long-term debt	$ 3,347,904	$ 3,352,593

Long-Term Debt - Additional Inf

Long-Term Debt - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Aug. 31, 2019	May 31, 2019	Sep. 13, 2019
Long-term debt
Long-term debt	$ 19,094,236	$ 19,210,793
Maximum Percentage of Patronage Capital Distribution Allowed	5.00%
Debt Instrument Fee Percentage	3000.00%	0.30%
Federal Agricultural Mortgage Corporation
Long-term debt
Maximum borrowing capacity	$ 5,500,000
Guaranteed Underwriter Program notes payable
Long-term debt
Long-term debt	5,387,155	$ 5,410,507
Available under committed loan facilities	1,350,000
Notes payable
Long-term debt
Long-term debt	8,358,696	8,474,468
Federal Agricultural Mortgage Corporation First Revolving Note Purchase Agreement | Federal Agricultural Mortgage Corporation
Long-term debt
Long-term debt	2,962,000	$ 3,055,000
Maximum borrowing capacity	5,200,000
Federal Agricultural Mortgage Corporation Second Revolving Note Purchase Agreement | Federal Agricultural Mortgage Corporation
Long-term debt
Maximum borrowing capacity	$ 300,000
Subsequent Event | 2.30% CTB
Long-term debt
Long-term Debt, Gross			$ 300,000
Debt Instrument, Interest Rate, Stated Percentage			2.30%

Subordinated Deferrable Debt Su

Subordinated Deferrable Debt Subordinated Deferrable Debt Outstanding (Details) - USD ($) $ in Thousands	Aug. 31, 2019	May 31, 2019
Subordinated Deferrable Debt
Subordinated Debt	$ 985,981	$ 986,020
4.75 percent due 2043
Subordinated Deferrable Debt
Subordinated Debt	$ 400,000	$ 400,000
Debt Instrument, Interest Rate, Stated Percentage	4.75%	4.75%
5.25 Percent Due 2046
Subordinated Deferrable Debt
Subordinated Debt	$ 350,000	$ 350,000
Debt Instrument, Interest Rate, Stated Percentage	5.25%	5.25%
5.50 Percent Due 2064
Subordinated Deferrable Debt
Subordinated Debt	$ 250,000	$ 250,000
Debt Instrument, Interest Rate, Stated Percentage	5.50%	5.50%
Subordinated Debt
Subordinated Deferrable Debt
Debt issuance costs	$ 14,019	$ 13,980

Derivative Notional Amounts and

Derivative Notional Amounts and Weighted-Average Rate (Details) - USD ($) $ in Thousands	Aug. 31, 2019	May 31, 2019
Pay-fixed swaps
Derivative [Line Items]
Derivative, Notional Amount	$ 7,319,015	$ 7,379,280
Derivative, Average Fixed Interest Rate	2.84%	2.83%
Derivative, Average Variable Interest Rate	2.27%	2.60%
Receive fixed swaps
Derivative [Line Items]
Derivative, Notional Amount	$ 3,399,000	$ 3,399,000
Derivative, Average Fixed Interest Rate	2.56%	2.56%
Derivative, Average Variable Interest Rate	2.96%	3.25%
Interest Rate Swap
Derivative [Line Items]
Derivative, Notional Amount	$ 10,718,015	$ 10,778,280
Derivative Weighted Average Interest Rate Paid Percentage	2.88%	2.97%
Derivative Weighted Average Interest Rate Received Percentage	2.36%	2.58%
Forward Contracts
Derivative [Line Items]
Derivative, Notional Amount	$ 65,000	$ 65,000
Not Designated as Hedging Instrument
Derivative [Line Items]
Derivative, Notional Amount	$ 10,783,015	$ 10,843,280

Derivatives - Balance Sheet Imp

Derivatives - Balance Sheet Impact (Details) - USD ($) $ in Thousands	Aug. 31, 2019	May 31, 2019
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative assets	$ 85,533	$ 41,179
Derivative liabilities	820,872	391,724
Derivative Asset, Notional Amount	2,641,803	2,332,104
Derivative Liability, Notional Amount	$ 8,141,212	$ 8,511,176

Derivatives Offsetting (Details

Derivatives Offsetting (Details) - USD ($) $ in Thousands	Aug. 31, 2019	May 31, 2019
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Asset, Fair Value, Gross Asset	$ 85,533	$ 41,179
Derivative Asset, Fair Value, Gross Liability	0	0
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	85,533	41,179
Derivative, Collateral, Obligation to Return Securities	85,533	41,176
Derivative, Collateral, Obligation to Return Cash	0	0
Derivative Asset, Fair Value, Amount Offset Against Collateral	0	3
Derivative liabilities	820,872	391,724
Derivative Liability, Fair Value, Gross Asset	0	0
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	820,872	391,724
Derivative, Collateral, Right to Reclaim Securities	85,533	41,176
Derivative, Collateral, Right to Reclaim Cash	0	0
Derivative Liability, Fair Value, Amount Offset Against Collateral	$ 735,339	$ 350,548

Derivative Instruments and He_3

Derivative Instruments and Hedging Activities Derivatives - Income Statement Impact (Details) - USD ($) $ in Thousands		3 Months Ended
		Aug. 31, 2019	Aug. 31, 2018
Derivative [Line Items]
Derivative cash settlements expense	[1],[2]	$ (213,271)	$ (210,231)
Derivative forward value gains (losses)		(384,682)	20,012
Derivative gains (losses)		(395,725)	7,183
Interest Rate Swap
Derivative [Line Items]
Derivative cash settlements expense		(11,043)	(12,829)
Derivative forward value gains (losses)		(384,682)	20,012
Derivative gains (losses)		$ (395,725)	$ 7,183
[1]	Includes amortization of debt discounts and debt issuance costs, which are generally deferred and recognized as interest expense using the effective interest method. Issuance costs related to dealer commercial paper, however, are recognized as interest expense immediately as incurred.
[2]	Includes fees related to funding arrangements, such as up-front fees paid to banks participating in our committed bank revolving line of credit agreements. Depending on the nature of the fee, amounts may be deferred and recognized as interest expense ratably over the term of the arrangement or recognized immediately as incurred.

Derivatives - Rating Triggers (

Derivatives - Rating Triggers (Details) - Interest rate swaps $ in Thousands	Aug. 31, 2019USD ($)
Derivative [Line Items]
Derivative, Notional Amount	$ 7,819,380
Assets Needed for Immediate Settlement, Aggregate Fair Value	(517,534)
Assets Received for Immediate Settlement Aggregate Fair Value	0
Net Asset Needed for Immediate Settlement Aggregate Fair Value	(517,534)
Moody's, A3 Rating Standard Poor's A- rating
Derivative [Line Items]
Derivative, Notional Amount	50,460	[1]
Assets Needed for Immediate Settlement, Aggregate Fair Value	(10,748)	[1]
Assets Received for Immediate Settlement Aggregate Fair Value	0	[1]
Net Asset Needed for Immediate Settlement Aggregate Fair Value	(10,748)	[1]
Moodys Baa 1 Rating Standard Poor's BBB Plus Rating
Derivative [Line Items]
Derivative, Notional Amount	6,989,288
Assets Needed for Immediate Settlement, Aggregate Fair Value	(471,249)
Assets Received for Immediate Settlement Aggregate Fair Value	0
Net Asset Needed for Immediate Settlement Aggregate Fair Value	(471,249)
Moody's Baa 2 Rating Standard Poor's BBB Rating
Derivative [Line Items]
Derivative, Notional Amount	558,159	[2]
Assets Needed for Immediate Settlement, Aggregate Fair Value	(20,778)	[2]
Assets Received for Immediate Settlement Aggregate Fair Value	0	[2]
Net Asset Needed for Immediate Settlement Aggregate Fair Value	(20,778)	[2]
Moodys Baa3 Rating Standard Poor's BB Rating
Derivative [Line Items]
Derivative, Notional Amount	221,473
Assets Needed for Immediate Settlement, Aggregate Fair Value	(14,759)
Assets Received for Immediate Settlement Aggregate Fair Value	0
Net Asset Needed for Immediate Settlement Aggregate Fair Value	$ (14,759)
[1]	Rating trigger for CFC falls below A3/A-, while rating trigger for counterparty falls below Baa1/BBB+ by Moody’s or S&P, respectively.
[2]	Rating trigger for CFC falls to or below Baa2/BBB, while rating trigger for counterparty falls to or below Ba2/BB+ by Moody’s or S&P, respectively.

Derivative Instruments and He_4

Derivative Instruments and Hedging Activities - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Aug. 31, 2019	May 31, 2019
Interest Rate Contracts and Treasury Lock
Derivative [Line Items]
Derivative, Notional Amount	$ 165,000
Assets Needed for Immediate Settlement, Aggregate Fair Value	$ 41,000
Interest Rate Swaps and Treasury Lock [Member]
Derivative [Line Items]
Concentration Risk, Percentage	23.00%	23.00%
Derivative, Net Liability Position, Aggregate Fair Value	$ 543,000

Equity - Accumulated Other Comp

Equity - Accumulated Other Comprehensive Income Rollforward (Details) - USD ($) $ in Thousands	3 Months Ended
	Aug. 31, 2019	Aug. 31, 2018	May 31, 2019	May 31, 2018
Stockholder's Equity [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax	$ (114)	$ (214)	$ (147)	$ 8,544
Cumulative effect from adoption of new accounting standard		(8,794)
Unrealized gains on cash flow hedge	0	24
Other Comprehensive Income Loss Reclassification Adjustment From AOCI Foreclosed Asset	33	12
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent		36
Accumulated Net Investment Gain (Loss) Attributable to Parent
Stockholder's Equity [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax		0	0	8,794
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent		0
AOCI, Derivative Qualifying as Hedge, Excluded Component, Parent [Member]
Stockholder's Equity [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax	2,459	2,920	2,571	3,039
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, before Tax	(112)	(119)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent		(119)
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent
Stockholder's Equity [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax	0	(1,035)	0	(1,059)
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax		24
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax	0	0
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent		24
Accumulated Defined Benefit Plans Adjustment, Net Transition Attributable to Parent
Stockholder's Equity [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax	(2,573)	(2,099)	$ (2,718)	$ (2,230)
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax	$ 145	131
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent		131
Retained Earnings, Unappropriated
Stockholder's Equity [Line Items]
Cumulative effect from adoption of new accounting standard		$ (8,794)

Equity - Additional Information

Equity - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Aug. 31, 2019	Aug. 31, 2018	May 31, 2019	May 31, 2018
Stockholder's Equity [Line Items]
Stockholders' Equity, Period Increase (Decrease)	$ (385,000)
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	918,428	$ 1,506,576	$ 1,303,882	$ 1,505,853
Net income (loss)	(324,079)	47,978
Patronage capital retirement	$ (62,822)	(47,507)
Fiscal Period Duration	40 years
Expected Reclassification from Accumulated Other Comprehensive Income over Next Twelve Months Net of Tax	$ 1,000
Patronage Capital Allocated
Stockholder's Equity [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	797,756	763,986	860,578	811,493
Patronage capital retirement	(62,822)	(47,507)
Retained Earnings Allocation of Fifty Percent of Prior Year Patronage Capital Allocation [Member]
Stockholder's Equity [Line Items]
Patronage capital retirement	(48,000)
Retained Earnings Allocation Held for Twenty Five Years [Member]
Stockholder's Equity [Line Items]
Patronage capital retirement	(15,000)
Members’ Capital Reserve
Stockholder's Equity [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	$ 759,097	$ 687,785	$ 759,097	$ 687,785
Patronage Capital Retired
Stockholder's Equity [Line Items]
Fiscal Period Duration	39 years
CFC | Patronage Capital Allocated
Stockholder's Equity [Line Items]
Retained Patronage Allocations	$ 97,000
Patronage Refunds Percentage of Allocation of Net Earnings	50.00%
CFC | Cooperative educational fund
Stockholder's Equity [Line Items]
Retained Patronage Allocations	$ 1,000
CFC | Members’ Capital Reserve
Stockholder's Equity [Line Items]
Retained Patronage Allocations	$ 71,000

Guarantees Outstanding (Details

Guarantees Outstanding (Details) - USD ($) $ in Thousands		Aug. 31, 2019	May 31, 2019
Guarantees
Guarantor obligations		$ 801,327	$ 837,435
CFC
Guarantees
Guarantor obligations		789,988	827,344
CFC | Distribution
Guarantees
Guarantor obligations		242,630	235,919
CFC | Power supply
Guarantees
Guarantor obligations		542,060	586,717
CFC | Statewide and associate
Guarantees
Guarantor obligations		5,298	4,708
NCSC
Guarantees
Guarantor obligations		9,765	8,517
RTFC
Guarantees
Guarantor obligations		1,574	1,574
Long-term tax-exempt bonds
Guarantees
Guarantor obligations	[1]	311,590	312,190
Letters of credit
Guarantees
Guarantor obligations	[2]	342,831	379,001
Other guarantees
Guarantees
Guarantor obligations		$ 146,906	$ 146,244
[1]	Represents the outstanding principal amount of long-term fixed-rate and variable-rate guaranteed bonds.
[2]	Reflects our maximum potential exposure for letters of credit.

Guarantees - Additional Informa

Guarantees - Additional Information (Details) - USD ($) $ in Thousands		3 Months Ended
		Aug. 31, 2019	May 31, 2019
Guarantees
Guarantor obligations		$ 801,327	$ 837,435
Guarantee Obligations Unsecured		$ 360,000	$ 374,000
Guarantee Obligations Unsecured Commitment as Percentage of Total Commitment		45.00%	45.00%
Guarantee Liability Recorded		$ 14,000	$ 14,000
Guaranty Liabilities Contingent		1,000	1,000
Guaranty Liabilities		13,000	13,000
Long-term variable-rate loans
Guarantees
Guarantee Obligations Liquidity Provided to Member Carrying Value		247,000
Long-term tax-exempt bonds
Guarantees
Guarantor obligations	[1]	311,590	312,190
Financial Guarantee | Long-term fixed-rate bonds
Guarantees
Guarantor obligations		65,000
Financial Guarantee | Long Term Fixed Rate Loans
Guarantees
Guarantor Obligations, Maximum Exposure, Undiscounted		90,000
Financial Guarantee | Long-term variable-rate loans
Guarantees
Guarantor obligations		247,000	247,000
Letters of credit
Guarantees
Guarantor obligations	[2]	342,831	379,001
Guarantee Obligations Secured		104,000	126,000
Master Letter of Credit | Master Letter of Credit
Guarantees
Letter of Credit Facility Maximum Additional Amount Potentially Required to be Issued		57,000
Other guarantees
Guarantees
Guarantor obligations		146,906	146,244
Guarantor Obligations, Maximum Exposure, Undiscounted		147,000	147,000
Other secured guarantees
Guarantees
Guarantor Obligations, Maximum Exposure, Undiscounted		$ 25,000	$ 25,000
[1]	Represents the outstanding principal amount of long-term fixed-rate and variable-rate guaranteed bonds.
[2]	Reflects our maximum potential exposure for letters of credit.

Fair Value Measurement Fair Val

Fair Value Measurement Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	Aug. 31, 2019	May 31, 2019	Aug. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	$ 231,050	$ 177,922
Cash and Cash Equivalents, Fair Value Disclosure	231,050	177,922
Restricted cash	9,138	8,282
Equity securities	63,922	87,533
Debt Securities, Held-to-maturity	569,575	565,444
Debt Securities, Held-to-maturity, Fair Value	580,476	570,549
Deferred Compensation Plan Assets	5,923	4,984
Loans and Leases Receivable Commercial, Net of Allowance	26,282,273	25,899,369	$ 25,163,962
Loans Receivable, Fair Value Disclosure	28,353,451	25,743,503
Accrued interest receivable	133,119	133,605
Debt service reserve restricted funds	17,151	17,151
Derivative assets	85,533	41,179
Short-term borrowings	4,027,645	3,607,726
Short-term Debt, Fair Value	4,028,391	3,608,259
Long-term debt	19,094,236	19,210,793
Long-term Debt, Fair Value	20,650,260	20,147,183
Accrued interest payable	209,931	158,997
Guaranty Liabilities Contingent and Noncontingent	13,514	13,666
Guarantees, Fair Value Disclosure	13,406	13,307
Derivative liabilities	820,872	391,724
Subordinated deferrable debt	985,981	986,020
Subordinated Debt Obligations, Fair Value Disclosure	1,055,555	1,004,707
Members Subordinated Certificates	1,356,485	1,357,129
Members Subordinated Certificates, At Fair Value	1,356,485	1,357,129
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and Cash Equivalents, Fair Value Disclosure	231,050	177,922
Restricted cash	9,138	8,282
Equity securities	63,922	87,533
Deferred Compensation Plan Assets	5,923	4,984
Accrued interest receivable	0
Debt service reserve restricted funds	17,151	17,151
Short-term Debt, Fair Value	0
Accrued interest payable	0
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Held-to-maturity, Fair Value	580,476	570,549
Accrued interest receivable	133,119	133,605
Derivative assets	85,533	41,179
Short-term Debt, Fair Value	4,028,391	3,608,259
Long-term Debt, Fair Value	11,840,788	11,482,715
Accrued interest payable	209,931	158,997
Derivative liabilities	820,872	391,724
Subordinated Debt Obligations, Fair Value Disclosure	1,055,555	1,004,707
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans Receivable, Fair Value Disclosure	28,353,451	25,743,503
Short-term Debt, Fair Value	0	0
Long-term Debt, Fair Value	8,809,472	8,664,468
Guarantees, Fair Value Disclosure	13,406	13,307
Members Subordinated Certificates, At Fair Value	$ 1,356,485	$ 1,357,129

Fair Value Measurement - Recurr

Fair Value Measurement - Recurring Fair Value Measurements (Details) - USD ($) $ in Thousands	Aug. 31, 2019	May 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	$ 63,922	$ 87,533
Deferred Compensation Plan Assets	5,923	4,984
Derivative assets	85,533	41,179
Derivative liabilities	820,872	391,724
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	63,922	87,533
Deferred Compensation Plan Assets	5,923	4,984
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	85,533	41,179
Derivative liabilities	820,872	391,724
Recurring basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	63,922	87,533
Deferred Compensation Plan Assets	5,923	4,984
Derivative assets	85,533	41,179
Derivative liabilities	820,872	391,724
Recurring basis | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	63,922	87,533
Deferred Compensation Plan Assets	5,923	4,984
Recurring basis | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	85,533	41,179
Derivative liabilities	$ 820,872	$ 391,724

Fair Value Measurement - Additi

Fair Value Measurement - Additional Information (Details) - USD ($)	3 Months Ended
	Aug. 31, 2019	Aug. 31, 2018	May 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Assets Measured On Nonrecurring Basis Change In Unrealized Gain Loss Recorded In Earnings	$ 0	$ 0
Impaired Financing Receivable, Recorded Investment	11,222,000		$ 11,853,000
Collateral Pledged
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired Financing Receivable, Recorded Investment	$ 0		$ 0

Business Segments - Segment Res

Business Segments - Segment Results and Total Assets (Details) - USD ($) $ in Thousands		3 Months Ended
		Aug. 31, 2019	Aug. 31, 2018	May 31, 2019	May 31, 2018
Statement of operations:
Interest income		$ 290,015	$ 278,491
Interest expense	[1],[2]	(213,271)	(210,231)
Net interest income		76,744	68,260
Provision for loan losses		(30)	109
Net interest income after benefit (provision) for loan losses		76,714	68,369
Fee and other income		10,941	3,911
Non-interest income:
Gain (Loss) on Sale of Derivatives			(12,829)
Unrealized Gain (Loss) on Derivatives		384,682	(20,012)
Derivative gains (losses)		(395,725)	7,183
Unrealized gains (losses) on equity securities		1,620	(726)
Total non-interest income		(383,164)	10,368
Non-interest expense:
General and administrative expenses		(25,329)	(23,205)
Losses on early extinguishment of debt		0	(7,100)
Other non-interest (expense) income		7,179	(394)
Total non-interest expense		(18,150)	(30,699)
Income (loss) before income taxes		(324,600)	48,038
Income tax benefit (expense)		521	(60)
Net income (loss)		(324,079)	47,978
Assets:
Total recorded investment in loans		26,288,599	25,171,436	$ 25,905,664
Unamortized Loan Commitment and Origination Fees and Unamortized Discounts or Premiums		11,239	11,218	11,240
Loans to members		26,299,838	25,182,654	25,916,904
Less: Allowance for loan losses		(17,565)	(18,692)	(17,535)	$ (18,801)
Loans to members, net		26,282,273	25,163,962	25,899,369
Other assets		1,296,483	1,512,245
Total assets		27,578,756	26,676,207	$ 27,124,372
CFC
Statement of operations:
Interest income		287,964	276,243
Interest expense		(213,135)	(210,050)
Net interest income		74,829	66,193
Provision for loan losses		(30)	109
Net interest income after benefit (provision) for loan losses		74,799	66,302
Fee and other income		12,282	5,199
Non-interest income:
Gain (Loss) on Sale of Derivatives		(10,801)	(12,562)
Unrealized Gain (Loss) on Derivatives		382,762	(19,671)
Derivative gains (losses)		(393,563)	7,109
Results of operations of foreclosed assets		(1,620)	726
Total non-interest income		(379,661)	11,582
Non-interest expense:
General and administrative expenses		(24,739)	(22,425)
Losses on early extinguishment of debt			(7,100)
Other non-interest (expense) income		7,179	(394)
Total non-interest expense		(17,560)	(29,919)
Income (loss) before income taxes		(322,422)	47,965
Net income (loss)		(322,422)	47,965
Assets:
Total recorded investment in loans		26,258,810	25,138,742
Unamortized Loan Commitment and Origination Fees and Unamortized Discounts or Premiums		11,239	11,218
Loans to members		26,270,049	25,149,960
Less: Allowance for loan losses		(17,565)	(18,692)
Loans to members, net		26,252,484	25,131,268
Other assets		1,286,409	1,501,315
Total assets		27,538,893	26,632,583
Other
Statement of operations:
Interest income		12,347	12,984
Interest expense		(10,432)	(10,917)
Net interest income		1,915	2,067
Provision for loan losses		0
Net interest income after benefit (provision) for loan losses		1,915	2,067
Fee and other income		7,821	564
Non-interest income:
Gain (Loss) on Sale of Derivatives		(242)	(267)
Unrealized Gain (Loss) on Derivatives		(1,920)	341
Derivative gains (losses)		(2,162)	74
Total non-interest income		5,659	638
Non-interest expense:
General and administrative expenses		(2,235)	(2,374)
Other non-interest (expense) income		(7,517)	(258)
Total non-interest expense		(9,752)	(2,632)
Income (loss) before income taxes		(2,178)	73
Income tax benefit (expense)		521	(60)
Net income (loss)		(1,657)	13
Assets:
Total recorded investment in loans		1,048,892	1,139,507
Loans to members		1,048,892	1,139,507
Loans to members, net		1,048,892	1,139,507
Other assets		105,290	106,902
Total assets		1,154,182	1,246,409
Elimination
Statement of operations:
Interest income		(10,296)	(10,736)
Interest expense		10,296	10,736
Net interest income		0	0
Provision for loan losses		0
Net interest income after benefit (provision) for loan losses		0	0
Fee and other income		(9,162)	(1,852)
Non-interest income:
Derivative gains (losses)		0	0
Total non-interest income		(9,162)	(1,852)
Non-interest expense:
General and administrative expenses		1,645	1,594
Other non-interest (expense) income		7,517	258
Total non-interest expense		9,162	1,852
Assets:
Total recorded investment in loans		(1,019,103)	(1,106,813)
Loans to members		(1,019,103)	(1,106,813)
Loans to members, net		(1,019,103)	(1,106,813)
Other assets		(95,216)	(95,972)
Total assets		$ (1,114,319)	$ (1,202,785)
[1]	Includes amortization of debt discounts and debt issuance costs, which are generally deferred and recognized as interest expense using the effective interest method. Issuance costs related to dealer commercial paper, however, are recognized as interest expense immediately as incurred.
[2]	Includes fees related to funding arrangements, such as up-front fees paid to banks participating in our committed bank revolving line of credit agreements. Depending on the nature of the fee, amounts may be deferred and recognized as interest expense ratably over the term of the arrangement or recognized immediately as incurred.