Pension Plans (Details) - USD ($) $ in Thousands	3 Months Ended
Aug. 31, 2021	Aug. 31, 2020
Retirement Benefits [Abstract]
Interest cost	$ 542	$ 512
Expected return on assets	(917)	(731)
Amortization of net loss	0	56
Net periodic pension benefit	$ (375)	$ (163)

Amount of cost recognized for passage of time related to defined benefit plan.

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Name:	us-gaap_DefinedBenefitPlanInterestCost
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration