CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Thousands		12 Months Ended
		May 31, 2020	May 31, 2019	May 31, 2018
Income Statement [Abstract]
Interest income		$ 1,151,286	$ 1,135,670	$ 1,077,357
Interest expense	[1],[2]	(821,089)	(836,209)	(792,735)
Net interest income		330,197	299,461	284,622
Benefit (provision) for loan losses		(35,590)	1,266	18,575
Net interest income after benefit (provision) for loan losses		294,607	300,727	303,197
Non-interest income:
Fee and other income		22,961	15,355	17,578
Derivative gains (losses)		(790,151)	(363,341)	231,721
Investment securities losses		9,431	(1,799)	0
Total non-interest income		(757,759)	(349,785)	249,299
Non-interest expense:
Salaries and employee benefits		(54,522)	(49,824)	(51,422)
Other general and administrative expenses		(46,645)	(43,342)	(39,462)
Losses on early extinguishment of debt		(683)	(7,100)	0
Other non-interest expense		(25,588)	(1,675)	(1,943)
Total non-interest expense		(127,438)	(101,941)	(92,827)
Income (loss) before income taxes		(590,590)	(150,999)	459,669
Income tax benefit (expense)		1,160	(211)	(2,305)
Net income (loss)		(589,430)	(151,210)	457,364
Less: Net (income) loss attributable to noncontrolling interests		4,190	1,979	(2,178)
Net income (loss) attributable to CFC		$ (585,240)	$ (149,231)	$ 455,186

[1] (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] (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.