Note 13 - Accumulated Other Comprehensive (Loss) Income (Details) - Changes in Accumulated Other Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended
Aug. 31, 2015	Aug. 31, 2014
Changes in Accumulated Other Comprehensive Loss [Abstract]
Foreign exchange translation adjustment, pretax	$ (29)	$ (4,340)
Foreign exchange translation adjustment, after tax	22	(4,365)
Foreign exchange translation adjustment, tax	(51)	25
Changes in fair value of cash flow hedges, pretax	180	248
Changes in fair value of cash flow hedges, tax	120	131
Changes in fair value of cash flow hedges, after tax	60	117
Other comprehensive income (loss), pretax	151	(4,092)
Other comprehensive income (loss), tax	69	156
Other comprehensive income (loss), after tax	$ 82	$ (4,248)

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

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Amount before tax, after reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Amount after tax and reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Amount of tax expense (benefit), after reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Amount before tax, after reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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

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Amount of tax expense (benefit) allocated to other comprehensive income (loss).

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