Note 14 - Changes in Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	9 Months Ended
Feb. 29, 2016	Feb. 28, 2015
Foreign exchange translation adjustment	$ (3,949)	$ (26,246)
Foreign exchange translation adjustment	(269)	1,431
Foreign exchange translation adjustment	(3,680)	(27,677)
Changes in fair value of cash flow hedges	417	553
Changes in fair value of cash flow hedges	168	242
Changes in fair value of cash flow hedges	249	311
	(3,532)	(25,693)
	(101)	1,673
	$ (3,431)	$ (27,366)

Amount before tax, after reclassification adjustments of other comprehensive income (loss).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 45
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