Note 12 - Accumulated Other Comprehensive (Loss) Income - Changes in Accumulated Other Comprehensive (Loss) Income (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Feb. 28, 2017	Feb. 29, 2016	Feb. 28, 2017	Feb. 29, 2016	May 31, 2016
Foreign exchange translation adjustments, pretax			$ (5,694)		$ (282)
Foreign exchange translation adjustments, tax			(141)		(108)
Foreign exchange translation adjustments, after tax	$ 930	$ 1,795	(5,553)	$ (3,680)	(174)
Changes in fair value of cash flow hedges, pretax			155		530
Changes in fair value of cash flow hedges, tax			61		199
Changes in fair value of cash flow hedges, after tax		111	94	249	331
Accumulated other comprehensive loss, pretax			(5,539)		248
Accumulated other comprehensive loss, tax			(80)		91
Accumulated other comprehensive loss, after tax	$ 930	$ 1,906	$ (5,459)	$ (3,431)	$ 157

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

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