Note 5 - Derivative Instruments (Details Textual) $ in Thousands, £ in Millions, ₨ in Billions	9 Months Ended
	May 31, 2017 USD ($)	May 31, 2017 GBP (£)	May 31, 2017 INR (₨)	Aug. 31, 2016 USD ($)
Foreign Exchange Contract [Member] | Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member]
Derivative Asset, Notional Amount	$ 64,080	£ 5.4	₨ 4.2	$ 91,690
Derivative Instruments, Gain (Loss) Reclassification from Accumulated OCI to Income, Estimated Net Amount to be Transferred	$ 2,100
United Kingdom, Pounds
Percent of Foreign Exchange Contracts Hedged	50.00%
United Kingdom, Pounds | Foreign Exchange Contract [Member] | Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member]
Derivative Asset, Notional Amount	$ 7,560			33,280
India, Rupees
Percent of Foreign Exchange Contracts Hedged	75.00%
India, Rupees | Foreign Exchange Contract [Member] | Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member]
Derivative Asset, Notional Amount	$ 56,520			$ 58,410