Changes in Equity - Summary of Changes in AOCI (Detail) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Feb. 29, 2024	Feb. 28, 2023	Feb. 29, 2024	Feb. 28, 2023
Accumulated Other Comprehensive Income Loss [Line Items]
Balance		$ 1,923,967	$ 1,639,292	$ 1,821,628	$ 1,613,962
Income tax effect		(2,553)	(9,571)	(4,261)	(5,265)
Separation of Worthington Steel		(1,030,899)
Balance		914,442	1,715,258	914,442	1,715,258
Foreign Currency Translation
Accumulated Other Comprehensive Income Loss [Line Items]
Balance				(22,123)	(15,310)
Other comprehensive income (loss) before reclassifications				1,555	(7,549)
Income tax effect				88	(131)
Separation of Worthington Steel				10,874
Balance		(9,606)	(22,990)	(9,606)	(22,990)
Pension Liability Adjustment
Accumulated Other Comprehensive Income Loss [Line Items]
Balance				(1,730)	(6,244)
Other comprehensive income (loss) before reclassifications				60	(619)
Reclassification adjustments to net earnings	[1],[2]			8,867	4,774
Income tax effect				(2,125)	(975)
Separation of Worthington Steel				(5,984)
Balance		(912)	(3,064)	(912)	(3,064)
Cash Flow Hedges
Accumulated Other Comprehensive Income Loss [Line Items]
Balance				674	(1,296)
Other comprehensive income (loss) before reclassifications				14,893	(2,999)
Reclassification adjustments to net earnings	[1],[2]			(5,753)	24,200
Income tax effect				(2,224)	(4,159)
Separation of Worthington Steel				(5,607)
Balance		1,983	(15,746)	1,983	(15,746)
AOCI
Accumulated Other Comprehensive Income Loss [Line Items]
Balance		(14,141)	(46,536)	(23,179)	(22,850)
Other comprehensive income (loss) before reclassifications				16,508	(11,167)
Reclassification adjustments to net earnings	[1],[2]			3,114	28,974
Income tax effect				(4,261)	(5,265)
Separation of Worthington Steel		(717)		(717)
Balance		$ (8,535)	$ (10,308)	$ (8,535)	$ (10,308)

[1] Cash flow hedges – Disclosure of reclassification adjustments classified within continuing operations is provided in “Note Q – Derivative Financial Instruments and Hedging Activities.” The residual amount relates to Worthington Steel and has been presented within discontinued operations.

[2] Pension liability adjustment – Reflects the acceleration of deferred pension costs in AOCI related to separate pension lift-out transactions completed in February 2024 and August 2022, respectively, to transfer the pension benefit obligation under The Gerstenslager Company Bargaining Unit Employees’ Pension Plan to third-party insurance companies.