Retirement-Related Benefit Plans' Impact on Income Before Income Taxes (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Feb. 28, 2019	Feb. 28, 2018	Feb. 28, 2019	Feb. 28, 2018
Pension Benefits | Domestic
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	$ 9,382	$ 9,465	$ 28,146	$ 28,395
Interest cost	5,497	4,379	16,491	13,137
Expected return on plan assets	(8,467)	(8,086)	(25,401)	(24,258)
Prior service cost (credit)	29	29	87	87
Net actuarial (gains) losses recognized	3,272	3,618	9,816	10,854
Net Periodic Benefit (Credit) Cost	9,713	9,405	29,139	28,215
Pension Benefits | Non-U.S. Plans
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	1,219	1,175	3,657	3,525
Interest cost	1,399	1,145	4,197	3,435
Expected return on plan assets	(2,051)	(1,978)	(6,153)	(5,934)
Prior service cost (credit)	(8)	(6)	(24)	(18)
Net actuarial (gains) losses recognized	319	451	957	1,353
Net Periodic Benefit (Credit) Cost	878	787	2,634	2,361
Postretirement Benefits | Domestic
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Interest cost	48	43	144	129
Prior service cost (credit)	(55)	(55)	(165)	(165)
Net actuarial (gains) losses recognized	(6)	6	(18)	18
Net Periodic Benefit (Credit) Cost	(13)	(6)	(39)	(18)
Postretirement Benefits | Non-U.S. Plans
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	392	311	1,176	933
Interest cost	291	224	873	672
Net actuarial (gains) losses recognized	115	79	345	237
Net Periodic Benefit (Credit) Cost	$ 798	$ 614	$ 2,394	$ 1,842