CONSOLIDATED STATEMENTS OF OPERATIONS (UNAUDITED) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Nov. 30, 2025	Nov. 30, 2024	Nov. 30, 2025	Nov. 30, 2024
Income Statement [Abstract]
Interest income	$ 445,674	$ 419,877	$ 893,120	$ 837,996
Interest expense	(373,666)	(354,443)	(750,135)	(710,903)
Net interest income	72,008	65,434	142,985	127,093
Provision for credit losses	(1,221)	(870)	(2,808)	(1,823)
Net interest income after provision for credit losses	70,787	64,564	140,177	125,270
Non-interest income (loss):
Fee and other income	6,687	5,424	13,762	11,092
Derivative gains (losses)	(18,641)	109,038	(50,845)	(89,287)
Investment securities gains (losses)	(1,027)	2,097	418	6,228
Total non-interest income (loss)	(12,981)	116,559	(36,665)	(71,967)
Non-interest expense:
Salaries and employee benefits	(19,262)	(17,439)	(39,238)	(34,627)
Other general and administrative expenses	(18,221)	(18,488)	(39,014)	(37,592)
Other non-interest expense	(759)	(247)	(1,034)	(565)
Total non-interest expense	(38,242)	(36,174)	(79,286)	(72,784)
Income (loss) before income taxes	19,564	144,949	24,226	(19,481)
Income tax (provision) benefit	(6)	(146)	14	(42)
Net income (loss)	19,558	144,803	24,240	(19,523)
Less: Net (income) loss attributable to noncontrolling interests	39	(360)	123	122
Net income (loss) attributable to CFC	$ 19,597	$ 144,443	$ 24,363	$ (19,401)