Note 5 - Derivative Instruments - Derivatives in Cash Flow Hedging Relationships (Details) - Cash Flow Hedging [Member] - Designated as Hedging Instrument [Member] - Foreign Exchange Contract [Member] - Selling, General and Administrative Expenses [Member] - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	May 31, 2017	May 31, 2016	May 31, 2017	May 31, 2016
Foreign currency forward contracts	$ (403)	$ (12)	$ (2,788)	$ 40
Foreign currency forward contracts	$ 3,467	$ 3,900	$ 4,006	$ 404