Note 11- Stock-based Compensation - Stock Option Activity (Details) - USD ($)	12 Months Ended
	Aug. 31, 2016	Aug. 31, 2015
Number of shares, Outstanding (in shares)	241,734	239,000
Weighted average exercise price, Outstanding (in dollars per share)	$ 13.72	$ 11.66
Number of shares, Options granted (in shares)	53,447	45,067
Weighted average exercise price, Options granted (in dollars per share)	$ 14.85	$ 20.10
Number of shares, Options exercised (in shares)	0	(38,333)
Weighted average exercise price, Options exercised (in dollars per share)	$ 0	$ 9
Number of shares, Options terminated (in shares)	(12,000)	(4,000)
Weighted average exercise price, Options terminated (in dollars per share)	$ 13.38	$ 10.20
Number of shares, Outstanding (in shares)	283,181	241,734
Weighted average exercise price, Outstanding (in dollars per share)	$ 13.95	$ 13.72
Aggregate intrinsic value, Outstanding	$ 392,370
Number of shares, Exercisable (in shares)	188,600
Weighted average exercise price, Exercisable (in dollars per share)	$ 13.45
Aggregate intrinsic value, Exercisable	$ 336,683