Employee Pension Plans - Other Changes in Plan Assets And Benefit Obligations Recognized in OCI (Detail) - USD ($) $ in Thousands	12 Months Ended
May 31, 2020	May 31, 2019
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Net loss	$ (7,596)	$ (3,227)
Amortization of net loss	553	441
Extraordinary charges		759
Total recognized in other comprehensive loss	(7,043)	(2,027)
Total recognized in net periodic benefit cost and other comprehensive income	$ 7,095	$ 2,839

Amount, after tax and reclassification adjustment, of (increase) decrease in accumulated other comprehensive income for defined benefit plan, attributable to parent.

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