Relationship between Plans Benefit Obligations and Assets (Detail) - Pension Benefits - USD ($) $ in Thousands	May 31, 2021	May 31, 2020
U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Plans with projected benefit obligations in excess of plan assets, benefit obligation	$ 822,073	$ 762,739
Plans with accumulated benefit obligations in excess of plan assets, benefit obligation	702,315	662,197
Plans with projected benefit obligations in excess of plan assets, plan asset	672,377	516,550
Plans with accumulated benefit obligations in excess of plan assets, plan asset	672,377	516,550
Non-U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Plans with projected benefit obligations in excess of plan assets, benefit obligation	45,294	163,589
Plans with accumulated benefit obligations in excess of plan assets, benefit obligation	43,522	150,478
Plans with assets in excess of projected benefit obligations	186,734	46,689
Plans with assets in excess of accumulated benefit obligations	173,490	46,689
Plans with projected benefit obligations in excess of plan assets, plan asset	30,421	134,791
Plans with accumulated benefit obligations in excess of plan assets, plan asset	30,421	134,598
Plans with assets in excess of projected benefit obligations, plan asset	209,432	60,083
Plans with assets in excess of accumulated benefit obligations, plan asset	$ 209,432	$ 60,276