Amounts Recognized in Other Comprehensive Income, and Reclassified into Income (Detail) (Euro denominated long-term debt, USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Feb. 28, 2014	Feb. 28, 2013	Feb. 28, 2014	Feb. 28, 2013
Euro denominated long-term debt
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Other Comprehensive Income	$ (94)	$ (143)	$ (856)	$ (791)
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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Period Type:	duration