Note 16 - Long-term Debt (Details Textual) - Revolving Credit Facility [Member] - USD ($)			3 Months Ended	6 Months Ended
	Sep. 21, 2015	Feb. 06, 2015	Feb. 29, 2016	Feb. 29, 2016	Feb. 28, 2015	Aug. 31, 2015
The Loan [Member] | Eurodollar [Member]
Debt Instrument, Basis Spread on Variable Rate		0.50%
The Loan [Member] | Maximum [Member]
Amortization of Financing Costs				$ 100,000
The Loan [Member]
Line of Credit Facility, Commitment Fee Amount				0
Line of Credit Facility, Maximum Borrowing Capacity			$ 300,000,000	300,000,000		$ 35,000,000
Long-term Line of Credit		$ 35,000,000	300,000,000	300,000,000		$ 35,000,000
Debt Instrument, Term		3 years
Second Amendment, Loan [Member] | Eurodollar [Member]
Debt Instrument, Basis Spread on Variable Rate	0.75%
Second Amendment, Loan [Member]
Line of Credit Facility, Maximum Amount Of Additional Borrowings	$ 400,000,000
Line of Credit Facility, Minimum Borrowing Amount Required for Additional Borrowings	25,000,000
Additional Long-Term Line of Credit	$ 265,000,000
Line of Credit Facility, Maximum Borrowing Capacity		$ 35,000,000
Line of Credit Facility, Maximum Amount Of Additional Borrowings		265,000,000
Line of Credit Facility, Minimum Borrowing Amount Required for Additional Borrowings		$ 25,000,000
Long-term Line of Credit			300,000,000	300,000,000
Interest Paid			$ 900,000	$ 1,300,000	$ 100,000