Nature of Operations and Summary of Significant Accounting Policies - Basic and Diluted EPS (Detail) - USD ($)	12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Earnings Per Share [Abstract]
Net income (loss)	$ 5,805,000	$ 5,531,000
Net Income Diluted	$ 5,805,000	$ 5,531,000
Weighted average common shares outstanding	14,614,000	14,595,000
Common Stock Equivalents	116,000	125,000
Diluted shares outstanding	14,730,000	14,720,000
Basic earnings per common share:
Basic earnings per share	$ 0.40	$ 0.38
Diluted earnings per common share:
Diluted earnings per share	$ 0.39	$ 0.38