Stock Compensation Plans: Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2021	Jan. 28, 2020	Jan. 27, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate intrinsic value of options exercised	$ 632	$ 605	$ 1,143
Share-based compensation, nonvested awards, future recognition of compensation cost, Stock Options	$ 777
Unrecognized compensation cost, weighted average period for recognition (in years)	2 years 1 month 28 days
2014 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized (in shares)					352,366
Number of shares available for grant (in shares)	5,036
Equity Incentive Plan 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized (in shares)				350,000
Number of shares available for grant (in shares)	176,050
Equity Incentive Plan 2019 | Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized (in shares)				300,000
Equity Incentive Plan 2019 | Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized (in shares)				50,000
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)	5 years
Expiration period (in years)	10 years
Stock options granted during period (in shares)	1,000	74,000	81,000
Stock options, aggregate grant date fair value	$ 9	$ 508	$ 502
Stock options vested during period (in shares)	59,990	52,960	49,928
Stock options vested during period, aggregate grant date fair value	$ 316	$ 239	$ 170
Number of unvested stock options (in shares)	130,120	191,910
Unvested stock awards, aggregate grant date fair value	$ 756	$ 428
Unvested stock options, aggregate intrinsic value	241
Stock options, outstanding, aggregate intrinsic value	$ 1,518	$ 2,130	$ 3,119
MRDP Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage (as a percent)	20.00%
Award vesting period (in years)	5 years
Expiration period (in years)	10 years