Note 14 - Stock-Based Compensation (Details) - Summary of Stock Option Weighted Average Assumptions, Employee (Employee Stock Purchase Plan [Member])	3 Months Ended		9 Months Ended
	May 31, 2014	May 31, 2013	May 31, 2014	May 31, 2013
Employee Stock Purchase Plan [Member]
Note 14 - Stock-Based Compensation (Details) - Summary of Stock Option Weighted Average Assumptions, Employee [Line Items]
Risk-free interest rate	0.04%	0.06%	0.04%	0.08%
Expected life (in months)	3 years	3 years	3 years	3 years
Expected volatility	13.30%	10.40%	10.80%	9.90%
Dividend yield	1.50%	1.44%	1.36%	1.36%