Net Income Per Common Share: Schedule of Earnings per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Earnings Per Share, Basic [Abstract]
Numerator – net income	$ 7,507	$ 5,485
Denominator – weighted average common shares outstanding (in shares)	8,232,273	8,356,066
Basic net income per common share (in dollars per share)	$ 0.91	$ 0.66
Earnings Per Share, Diluted [Abstract]
Effect of dilutive stock options (in shares)	86,460	92,834
Weighted average common shares and common stock equivalents (in shares)	8,318,733	8,448,900
Diluted net income per common share (in dollars per share)	$ 0.90	$ 0.65
Stock Options
Earnings Per Share, Diluted [Abstract]
Antidilutive securities excluded from computation of earnings per share (in shares)	182,000	210,052