Net Income Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Feb. 29, 2020	Feb. 28, 2019	Feb. 29, 2020	Feb. 28, 2019
Basic Earnings per Share
Net income	$ 7,879	$ 5,273	$ 15,241	$ 14,096
Less: Allocated to participating securities	69	41	118	110
Available to common shareholders	$ 7,810	$ 5,232	$ 15,123	$ 13,986
Basic weighted average shares outstanding	9,355,821	9,332,288	9,353,985	9,330,929
Net income per share - Basic (in dollars per share)	$ 0.83	$ 0.56	$ 1.62	$ 1.50
Diluted Earnings per Share
Net income	$ 7,879	$ 5,273	$ 15,241	$ 14,096
Less: Allocated to participating securities	69	41	118	110
Net income available to common shareholders	$ 7,810	$ 5,232	$ 15,123	$ 13,986
Basic weighted average shares outstanding	9,355,821	9,332,288	9,353,985	9,330,929
Additional dilutive common stock equivalents (in shares)	88,390	40,742	85,230	46,238
Diluted weighted average shares outstanding	9,444,211	9,373,030	9,439,215	9,377,167
Net income per share - Diluted (in dollars per share)	$ 0.83	$ 0.56	$ 1.60	$ 1.49
Antidilutive securities
Antidilutive stock options excluded from computation of earnings per share amount (in shares)	8,805	15,625	8,805	14,022