Changes in Equity - Summary of Changes in Accumulated Other Comprehensive Income (Loss) (Detail) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Feb. 28, 2021	Feb. 29, 2020	Feb. 28, 2021	Feb. 29, 2020
Accumulated Other Comprehensive Income Loss [Line Items]
Balance			$ 958,743	$ 966,433	$ 948,394
Income tax effect		$ (8,084)	(678)	(12,536)	(1,108)
Balance		1,463,185	972,193	1,463,185	972,193
Foreign Currency Translation
Accumulated Other Comprehensive Income Loss [Line Items]
Balance				(9,142)	(19,640)
Other comprehensive income (loss) before reclassifications				7,807	2,372
Reclassification adjustments to income	[1]			0	8,496
Income tax effect				809	0
Balance		(526)	(8,772)	(526)	(8,772)
Pension Liability Adjustment
Accumulated Other Comprehensive Income Loss [Line Items]
Balance				(21,886)	(17,855)
Other comprehensive income (loss) before reclassifications				392	271
Reclassification adjustments to income	[1]			0	1,326
Income tax effect				(127)	(351)
Balance		(21,621)	(16,609)	(21,621)	(16,609)
Cash Flow Hedges
Accumulated Other Comprehensive Income Loss [Line Items]
Balance				(4,189)	(5,969)
Other comprehensive income (loss) before reclassifications				54,143	(6,369)
Reclassification adjustments to income	[1]			4,445	9,859
Income tax effect				(13,218)	(757)
Balance		41,181	(3,236)	41,181	(3,236)
Accumulated Other Comprehensive Income (Loss), Net of Tax
Accumulated Other Comprehensive Income Loss [Line Items]
Balance			(30,338)	(35,217)	(43,464)
Other comprehensive income (loss) before reclassifications				62,342	(3,726)
Reclassification adjustments to income	[1]			4,445	19,681
Income tax effect				(12,536)	(1,108)
Balance		$ 19,034	$ (28,617)	$ 19,034	$ (28,617)

[1] (a)  The statement of earnings classification of amounts reclassified to income include: (1)  Foreign currency translation – result of $7,454,000 related to the sale of the cryogenics business in Turkey; and $1,042,000 related to the impairment of Nisshin, the Company’s former joint venture in China. (2)  Pension liability adjustment – result of the settlement of certain participant balances within the pension plan maintained by WAVE. (3)  Cash flow hedges – disclosed in “NOTE Q – Derivative Instruments and Hedging Activities”.