Other Comprehensive Income (Details 1) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Aug. 31, 2012	Aug. 31, 2011
Related tax effects allocated to each component of other comprehensive income
Foreign currency translation adjustments, Gross Amount	$ 3,038	$ 278
Foreign currency translation adjustments, Tax Effect	(908)	10
Foreign currency translation adjustments, Net Amount	2,130	288
Foreign currency hedge, Gross Amount	(112)	(34)
Foreign currency hedge, Tax Effect	44	13
Foreign currency hedge, Net Amount	(68)	(21)
Other Comprehensive Income (Loss), before Tax, Total	2,926	244
Total other comprehensive income, Tax Affect	(864)	23
Total other comprehensive income, Net Amount	$ 2,062	$ 267

Before tax amount of other comprehensive income (loss) attributable to both parent entity and noncontrolling interest.

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