Other Expense, Net (Detail) - USD ($) $ in Thousands	3 Months Ended
	Aug. 31, 2020	Aug. 31, 2019
Other Income And Expenses [Abstract]
Royalty (income) expense, net	$ (31)	$ 266
(Income) expense related to unconsolidated equity affiliates	(187)	91
Pension non-service costs	3,336	1,428
Other expense, net	$ 3,118	$ 1,785