Amounts Recognized in Other Comprehensive Income, and Reclassified into Income (Detail) (Euro denominated long-term debt, USD $) In Thousands, unless otherwise specified	12 Months Ended
May 31, 2013	May 31, 2012
Euro denominated long-term debt
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Other Comprehensive Income	$ (674)	$ 2,385
Gain (Loss) Reclassified from Other Comprehensive Income to Earnings

The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4C

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4D

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624177-113959

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration