Changes in Benefits Obligations and Plan Assets, Pension (Detail) - Pension Benefits - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Feb. 29, 2020	May 31, 2020	May 31, 2019	May 31, 2018
U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation at beginning of year		$ 660,277	$ 617,255
Service cost		39,425	37,528	$ 37,859
Interest cost		20,415	21,987	17,518
Benefits paid		(41,186)	(45,917)
Plan amendments			11
Actuarial losses		83,808	29,413
Benefit Obligation at End of Year		762,739	660,277	617,255
Balance at Beginning of Period		496,865	487,233
Actual return on plan assets		8,689	(2,272)
Employer contributions	$ 51,500	52,182	57,821
Benefits paid		(41,186)	(45,917)
Balance at End of Period		516,550	496,865	487,233
(Deficit) of plan assets versus benefit obligations at end of year		(246,189)	(163,412)
Net Amount Recognized		(246,189)	(163,412)
Accumulated Benefit Obligation		662,197	553,392
Non-U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation at beginning of year		205,967	194,149
Service cost		5,400	4,693	4,620
Interest cost		4,842	5,420	5,025
Benefits paid		(6,269)	(7,488)
Participant contributions		1,106	1,003
Plan amendments		(893)	(33)
Plan combination		922
Plan settlements/curtailments		(288)	(607)
Actuarial losses		2,718	17,286
Premiums paid		(99)	(97)
Currency exchange rate changes		(3,128)	(8,359)
Benefit Obligation at End of Year		210,278	205,967	194,149
Balance at Beginning of Period		187,112	188,960
Actual return on plan assets		9,899	6,737
Employer contributions		6,331	6,770
Participant contributions		1,106	1,003
Benefits paid		(6,269)	(7,488)
Plan combination		182
Premiums paid		(99)	(97)
Plan settlements/curtailments		(281)	(580)
Currency exchange rate changes		(3,107)	(8,193)
Balance at End of Period		194,874	187,112	$ 188,960
(Deficit) of plan assets versus benefit obligations at end of year		(15,404)	(18,855)
Net Amount Recognized		(15,404)	(18,855)
Accumulated Benefit Obligation		$ 197,167	$ 192,533