Note 19 - Commitments and Contingencies (Details Textual) $ in Thousands	12 Months Ended
	Aug. 31, 2017 USD ($) ft²	Aug. 31, 2016 USD ($)	Aug. 31, 2015 USD ($)
Operating Leases, Rent Expense	$ 48,400	$ 43,200	$ 38,600
Other Liabilities, Noncurrent	37,188	33,080
Letters of Credit Outstanding, Amount	1,900
Purchase Commitment, Remaining Minimum Amount Committed	81,000	67,500
Deferred Rent [Member]
Other Liabilities	37,400	34,400
Other Liabilities, Noncurrent	$ 33,500	$ 31,200
Non-cancelable Operating Lease [Member]
Area of Real Estate Property | ft²	1,143,000