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Stock Based Incentive Compensation - Narrative (Details) - USD ($)	12 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2019	Sep. 30, 2021	Sep. 30, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted	0	0
Outstanding stock option	0	0		500
Stock-based compensation expense	$ 1,127,000	$ 979,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	143,172	152,246
Employee Benefits and Share-based Compensation, Cash	$ 0
The 2015 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized					300,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized		400,000	300,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	245,404
Share-Based Compensation Arrangement by Share-Based Payment Award Expiration	10 years
Officers And Chief Executive Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	52,000	52,000
Chief Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	35,000	38,000
Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	20,000	20,000
Key Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	71,172	80,246
Restricted stock \| Officers And Chief Executive Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	4 years
Restricted stock \| Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	1 year
Restricted stock \| Key Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	4 years
Stock option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding stock option	0
Stock option \| The 2015 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding stock option	0