Pension Plan Assets Categorized Using Fair Value Hierarchy (Detail) - Pension Benefits - USD ($) $ in Thousands	May 31, 2021	May 31, 2020	May 31, 2019
U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Pension plans with Plan Assets	$ 672,377	$ 516,550	$ 496,865
U.S. Plans | U.S. Treasury and other government
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Pension plans with Plan Assets	20,752	12,973
U.S. Plans | State and Municipal Debt Obligations
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Pension plans with Plan Assets	767	508
U.S. Plans | Foreign Covered Bonds
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Pension plans with Plan Assets	1,068	715
U.S. Plans | Mortgage-backed securities
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Pension plans with Plan Assets	17,628	23,824
U.S. Plans | Corporate bonds
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Pension plans with Plan Assets	42,370	34,317
U.S. Plans | Large Cap Equity Securities
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Pension plans with Plan Assets	40,332	19,589
U.S. Plans | Equity Mutual Funds
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Pension plans with Plan Assets	346,790	241,426
U.S. Plans | Mutal Funds - Multi-class
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Pension plans with Plan Assets	150,838	118,205
U.S. Plans | Debt Mutual Funds
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Pension plans with Plan Assets	29,440	33,993
U.S. Plans | Cash and Cash Equivalents
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Pension plans with Plan Assets	22,224	30,830
U.S. Plans | Limited Partner
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Pension plans with Plan Assets	168	170
Non-U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Pension plans with Plan Assets	239,853	194,874	187,112
Non-U.S. Plans | Foreign Covered Bonds
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Pension plans with Plan Assets	717	603
Non-U.S. Plans | Cash and Cash Equivalents
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Pension plans with Plan Assets	77	67
Non-U.S. Plans | Pooled Equity Securities Funds
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Pension plans with Plan Assets	101,975	78,472
Non-U.S. Plans | Pooled Funds Fixed Income Securities
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Pension plans with Plan Assets	107,457	87,610
Non-U.S. Plans | Insurance Contracts
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Pension plans with Plan Assets	28,230	27,267
Non-U.S. Plans | Mutual funds
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Pension plans with Plan Assets	1,397	855
Quoted Prices in Active Markets for Identical Assets (Level 1) | U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Pension plans with Plan Assets	62,556	50,419
Quoted Prices in Active Markets for Identical Assets (Level 1) | U.S. Plans | Large Cap Equity Securities
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Pension plans with Plan Assets	40,332	19,589
Quoted Prices in Active Markets for Identical Assets (Level 1) | U.S. Plans | Cash and Cash Equivalents
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Pension plans with Plan Assets	22,224	30,830
Quoted Prices in Active Markets for Identical Assets (Level 1) | Non-U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Pension plans with Plan Assets	77	67
Quoted Prices in Active Markets for Identical Assets (Level 1) | Non-U.S. Plans | Cash and Cash Equivalents
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Pension plans with Plan Assets	77	67
Significant Other Observable Inputs (Level 2) | U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Pension plans with Plan Assets	609,653	465,961
Significant Other Observable Inputs (Level 2) | U.S. Plans | U.S. Treasury and other government
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Pension plans with Plan Assets	20,752	12,973
Significant Other Observable Inputs (Level 2) | U.S. Plans | State and Municipal Debt Obligations
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Pension plans with Plan Assets	767	508
Significant Other Observable Inputs (Level 2) | U.S. Plans | Foreign Covered Bonds
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Pension plans with Plan Assets	1,068	715
Significant Other Observable Inputs (Level 2) | U.S. Plans | Mortgage-backed securities
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Pension plans with Plan Assets	17,628	23,824
Significant Other Observable Inputs (Level 2) | U.S. Plans | Corporate bonds
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Pension plans with Plan Assets	42,370	34,317
Significant Other Observable Inputs (Level 2) | U.S. Plans | Equity Mutual Funds
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Pension plans with Plan Assets	346,790	241,426
Significant Other Observable Inputs (Level 2) | U.S. Plans | Mutal Funds - Multi-class
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Pension plans with Plan Assets	150,838	118,205
Significant Other Observable Inputs (Level 2) | U.S. Plans | Debt Mutual Funds
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Pension plans with Plan Assets	29,440	33,993
Significant Other Observable Inputs (Level 2) | Non-U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Pension plans with Plan Assets	211,546	167,540
Significant Other Observable Inputs (Level 2) | Non-U.S. Plans | Foreign Covered Bonds
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Pension plans with Plan Assets	717	603
Significant Other Observable Inputs (Level 2) | Non-U.S. Plans | Pooled Equity Securities Funds
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Pension plans with Plan Assets	101,975	78,472
Significant Other Observable Inputs (Level 2) | Non-U.S. Plans | Pooled Funds Fixed Income Securities
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Pension plans with Plan Assets	107,457	87,610
Significant Other Observable Inputs (Level 2) | Non-U.S. Plans | Mutual funds
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Pension plans with Plan Assets	1,397	855
Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Pension plans with Plan Assets	28,398	27,437	$ 28,015
Significant Unobservable Inputs (Level 3) | U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Pension plans with Plan Assets	168	170
Significant Unobservable Inputs (Level 3) | U.S. Plans | Limited Partner
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Pension plans with Plan Assets	168	170
Significant Unobservable Inputs (Level 3) | Non-U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Pension plans with Plan Assets	28,230	27,267
Significant Unobservable Inputs (Level 3) | Non-U.S. Plans | Insurance Contracts
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Pension plans with Plan Assets	$ 28,230	$ 27,267