Condensed Consolidated Statements of Comprehensive Income (Loss) (Unaudited) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Nov. 30, 2019	Nov. 30, 2018	Nov. 30, 2019	Nov. 30, 2018
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 241,600	$ 119,726	$ (82,479)	$ 167,704
Other comprehensive income (loss):
Unrealized gains on cash flow hedge	0	1,035	0	1,059
Reclassification of derivative gains to net income	(114)	(120)	(226)	(239)
Defined benefit plan adjustments	146	131	291	262
Other comprehensive income	32	1,046	65	1,082
Total comprehensive income (loss)	241,632	120,772	(82,414)	168,786
Less: Total comprehensive (income) loss attributable to noncontrolling interests	(8)	(466)	1,649	(479)
Total comprehensive income (loss) attributable to CFC	$ 241,624	$ 120,306	$ (80,765)	$ 168,307

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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