Segment Operations - Reconciliation of Segment Adjusted EBITDA from Continuing Operations to Earnings from Income Taxes from Continuing Operations (Detail) - USD ($) $ in Thousands	3 Months Ended					9 Months Ended
	Feb. 28, 2025		Feb. 29, 2024	Feb. 28, 2024		Feb. 28, 2025		Feb. 29, 2024	Feb. 28, 2024
Segment Reporting [Abstract]
Segment adjusted EBITDA from continuing operations	$ 81,812			$ 78,708		$ 201,985			$ 211,038
Reconciling items:
Unallocated Corporate and other	(8,033)			(11,837)		(23,556)			(23,209)
Depreciation and amortization	(11,950)		$ (11,949)	(11,949)		(35,707)			(36,238)
Interest expense, net	(628)			(50)		(2,150)			(1,596)
Stock-based compensation	(2,924)			(2,601)		(10,122)			(9,822)
Corporate costs eliminated at Separation									(19,343)
Restructuring and other expense, net	(5,374)	[1]	(698)	(698)	[1]	(9,152)	[1]		(704)	[1]
Separation costs			(2,999)	(2,999)				$ (12,465)	(12,465)
Pension settlement charge				(8,103)					(8,103)
Loss on extinguishment of debt								(1,534)	(1,534)
Gain on sale of assets in equity income									2,780
Earnings before income taxes from continuing operations	$ 52,579		$ 40,471	$ 40,471		$ 120,478		$ 100,804	$ 100,804

[1] Reflects the change in fair value of the contingent liability associated with the Ragasco earnout arrangement covering the 12-month period ended December 31, 2024. See “Note N – Acquisitions” for additional information.