Stock Compensation Plans: Narrative (Details) - USD ($)	12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2022	Jan. 28, 2020	Jan. 27, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate intrinsic value of options exercised	$ 655,000	$ 632,000	$ 605,000
Share-based compensation, nonvested awards, future recognition of compensation cost, Stock Options	$ 490,000
Unrecognized compensation cost, weighted average period for recognition (in years)	1 year 9 months 3 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)	15,576
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)	154,655
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
Stock options granted during period (in shares)	0	1,000	74,000
Stock options, aggregate grant date fair value		$ 9,000	$ 508,000
Stock options vested during period (in shares)	43,690	59,990	52,960
Stock options vested during period, aggregate grant date fair value	$ 235,000	$ 316,000	$ 239,000
Number of unvested stock options (in shares)	77,230	130,120
Unvested stock awards, aggregate grant date fair value	$ 468,000	$ 756,000
Unvested stock options, aggregate intrinsic value	312,000
Stock options, outstanding, aggregate intrinsic value	1,599,000	1,518,000	$ 2,130,000
Share-based payment expense	$ 233,000	$ 320,000
Stock Options | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)	3 years
Stock Options | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (in years)	5 years
MRDP Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiration period (in years)	10 years
Number of unvested stock awards (in shares)	49,015	26,150	0
Stock awards, granted during period (in shares)	28,815	26,150	0
Unvested restricted stock	$ 1,435,000
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost, weighted average period for recognition (in years)	2 years 6 months 10 days
Share-based payment expense	$ 157,000