Note 13 - Changes in Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	6 Months Ended
Nov. 30, 2015	Nov. 30, 2014
Foreign exchange translation adjustment	$ (5,732)	$ (13,625)
Foreign exchange translation adjustment	(257)	137
Foreign exchange translation adjustment	(5,475)	(13,762)
Changes in fair value of cash flow hedges	309	367
Changes in fair value of cash flow hedges	171	170
Changes in fair value of cash flow hedges	138	197
	(5,423)	(13,258)
	(86)	307
	$ (5,337)	$ (13,565)

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

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