Consolidated Statements of Changes in Equity (Unaudited) - USD ($) $ in Thousands	Total	Cumulative-effect adjustment from adoption of new accounting standard	Cumulative effect, period of adoption, adjusted balance	Membership Fees and Educational Fund	Membership Fees and Educational Fund Cumulative effect, period of adoption, adjusted balance	Patronage Capital Allocated	Patronage Capital Allocated Cumulative effect, period of adoption, adjusted balance	Members’ Capital Reserve	Members’ Capital Reserve Cumulative effect, period of adoption, adjusted balance	Unallocated Net Income (Loss)	Unallocated Net Income (Loss) Cumulative-effect adjustment from adoption of new accounting standard	Unallocated Net Income (Loss) Cumulative effect, period of adoption, adjusted balance	CFC Retained Equity	CFC Retained Equity Cumulative-effect adjustment from adoption of new accounting standard	CFC Retained Equity Cumulative effect, period of adoption, adjusted balance	Accumulated Other Comprehensive Income (Loss)	Accumulated Other Comprehensive Income (Loss) Cumulative effect, period of adoption, adjusted balance	Total CFC Equity	Total CFC Equity Cumulative-effect adjustment from adoption of new accounting standard	Total CFC Equity Cumulative effect, period of adoption, adjusted balance	Non-controlling Interests	Non-controlling Interests Cumulative effect, period of adoption, adjusted balance
Beginning balance at May. 31, 2020	$ 648,822	$ (3,900)	$ 644,922	$ 3,193	$ 3,193	$ 894,066	$ 894,066	$ 807,320	$ 807,320	$ (1,076,548)	$ (3,900)	$ (1,080,448)	$ 628,031	$ (3,900)	$ 624,131	$ (1,910)	$ (1,910)	$ 626,121	$ (3,900)	$ 622,221	$ 22,701	$ 22,701
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	305,108									304,432			304,432					304,432			676
Other comprehensive income	164															164		164
Patronage capital retirement	(59,857)					(59,857)							(59,857)					(59,857)
Other	1,382			(642)									(642)					(642)			2,024
Ending balance at Nov. 30, 2020	891,719			2,551		834,209		807,320		(776,016)			868,064			(1,746)		866,318			25,401
Beginning balance at Aug. 31, 2020	731,504			2,939		834,209		807,320		(936,032)			708,436			(1,827)		706,609			24,895
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	160,521									160,016			160,016					160,016			505
Other comprehensive income	81															81		81
Patronage capital retirement	0
Other	(387)			(388)									(388)					(388)			1
Ending balance at Nov. 30, 2020	891,719			2,551		834,209		807,320		(776,016)			868,064			(1,746)		866,318			25,401
Beginning balance at May. 31, 2021	1,399,879			3,125		923,970		909,749		(461,871)			1,374,973			(25)		1,374,948			24,931
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	45,397									45,204			45,204					45,204			193
Other comprehensive income	3,931															3,931		3,931
Patronage capital retirement	(59,979)					(57,565)							(57,565)					(57,565)			(2,414)
Other	1,757			(460)		0							(460)					(460)			2,217
Ending balance at Nov. 30, 2021	1,390,985			2,665		866,405		909,749		(416,667)			1,362,152			3,906		1,366,058			24,927
Beginning balance at Aug. 31, 2021	1,254,220			2,756		866,405		909,749		(551,765)			1,227,145			365		1,227,510			26,710
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	135,729									135,098			135,098					135,098			631
Other comprehensive income	3,541															3,541		3,541
Patronage capital retirement	(2,414)																				(2,414)
Other	(91)			(91)									(91)					(91)
Ending balance at Nov. 30, 2021	$ 1,390,985			$ 2,665		$ 866,405		$ 909,749		$ (416,667)			$ 1,362,152			$ 3,906		$ 1,366,058			$ 24,927