Retirement-Related Benefit Plans' Impact on Income Before Income Taxes (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Feb. 29, 2016	Feb. 28, 2015	Feb. 29, 2016	Feb. 28, 2015
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	$ 9,600		$ 28,700
Interest cost	6,100		18,300
Pension Benefits, U.S. Plans
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	8,202	$ 7,604	24,606	$ 22,732
Interest cost	4,499	5,046	13,497	15,050
Expected return on plan assets	(6,437)	(6,102)	(19,311)	(18,170)
Prior service cost (credit)	58	75	174	223
Net actuarial (gains) losses recognized	4,190	3,502	12,570	10,446
Net Periodic Benefit Cost	10,512	10,125	31,536	30,281
Pension Benefits, Non-U.S. Plans
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	1,067	1,231	3,201	3,693
Interest cost	1,319	1,891	3,965	5,673
Expected return on plan assets	(1,978)	(2,296)	(5,944)	(6,888)
Prior service cost (credit)		10		30
Net actuarial (gains) losses recognized	455	536	1,369	1,608
Settlement			91
Net Periodic Benefit Cost	863	1,372	2,682	4,116
Postretirement Benefits, U.S. Plans
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Interest cost	59	66	177	198
Prior service cost (credit)	(62)	(62)	(186)	(186)
Net actuarial (gains) losses recognized		(34)		(102)
Net Periodic Benefit Cost	(3)	(30)	(9)	(90)
Postretirement Benefits, Non-U.S. Plans
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	281	313	843	939
Interest cost	221	308	663	924
Net actuarial (gains) losses recognized	61	104	183	312
Net Periodic Benefit Cost	$ 563	$ 725	$ 1,689	$ 2,175