Changes in Accrued Restructuring Balances (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Aug. 31, 2013
Restructuring Cost and Reserve [Line Items]
Balance at May 31, 2013	$ 17,782
Charge to expense	128
Cash payments	(1,416)
Noncash and foreign exchange impacts	298
Balance at August 31, 2013	16,792
Long-Lived Asset Charges
Restructuring Cost and Reserve [Line Items]
Balance at May 31, 2013	4,729
Noncash and foreign exchange impacts	123
Balance at August 31, 2013	4,852
Employee Severance
Restructuring Cost and Reserve [Line Items]
Balance at May 31, 2013	12,656
Charge to expense	128
Cash payments	(1,416)
Noncash and foreign exchange impacts	165
Balance at August 31, 2013	11,533
Site Preparation and Equipment Relocation
Restructuring Cost and Reserve [Line Items]
Balance at May 31, 2013	397
Noncash and foreign exchange impacts	10
Balance at August 31, 2013	$ 407