Changes in Equity - Summary of Changes in AOCI (Detail) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Feb. 28, 2025	Feb. 29, 2024	Feb. 28, 2025	Feb. 29, 2024
Accumulated Other Comprehensive Income Loss [Line Items]
Balance		$ 912,958	$ 1,923,967	$ 891,012	$ 1,821,628
Income tax effect		(1,177)	(2,553)	(989)	(4,261)
Separation of Worthington Steel			(1,033,245)
Balance		938,521	914,442	938,521	914,442
Foreign Currency Translation
Accumulated Other Comprehensive Income Loss [Line Items]
Balance				(669)	(22,123)
OCI before reclassifications				(4,433)	1,555
Income tax effect				(1,006)	88
Separation of Worthington Steel					10,874
Balance		(6,108)	(9,606)	(6,108)	(9,606)
Pension Liability Adjustment
Accumulated Other Comprehensive Income Loss [Line Items]
Balance				(441)	(1,730)
OCI before reclassifications				16	60
Reclassification adjustments to net earnings	[1]				8,867
Income tax effect				151	(2,125)
Separation of Worthington Steel					(5,984)
Balance		(274)	(912)	(274)	(912)
Cash Flow Hedges
Accumulated Other Comprehensive Income Loss [Line Items]
Balance				1,564	674
OCI before reclassifications				207	14,893
Reclassification adjustments to net earnings	[1]			368	(5,753)
Income tax effect				(134)	(2,224)
Separation of Worthington Steel					(5,607)
Balance		2,005	1,983	2,005	1,983
AOCI
Accumulated Other Comprehensive Income Loss [Line Items]
Balance		(2,382)	(14,141)	454	(23,179)
OCI before reclassifications				(4,210)	16,508
Reclassification adjustments to net earnings	[1]			368	3,114
Income tax effect				(989)	(4,261)
Separation of Worthington Steel			(717)		(717)
Balance		$ (4,377)	$ (8,535)	$ (4,377)	$ (8,535)

[1] The statement of earnings classification of amounts reclassified to net income for cash flow hedges is disclosed in “Note O – Derivative Financial Instruments and Hedging Activities.”