Summary of Tax Effects of Each Component of Other Comprehensive Income (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Feb. 28, 2013	Feb. 29, 2012	Feb. 28, 2013	Feb. 29, 2012
Before-Tax amount
Foreign currency translation, before tax amount	$ (1,675)		$ 6,400
Pension liability adjustment, before tax amount	(43)		(298)
Cash flow hedges, before tax amount	724		2,501
Other comprehensive income, before tax amount	(994)		8,603
Tax Expense
Foreign currency translation, tax expense
Pension liability adjustment, tax expense	15		97
Cash flow hedges, tax expense	113		(1,008)
Other comprehensive income, tax expense	128		(911)
Net-of-Tax amount
Foreign currency translation	(1,675)	6,933	6,400	(4,439)
Pension liability adjustment	(28)	(431)	(201)	(382)
Cash flow hedges	837	167	1,493	(713)
Other comprehensive income	$ (866)	$ 6,669	$ 7,692	$ (5,534)