Statements of Changes in Stockholders' Equity - USD ($) $ in Thousands	Two Thousand Eighteen Dividend Reinvestment and Stock Purchase Plan [Member] Common Stock [Member]	Two Thousand Eighteen Dividend Reinvestment and Stock Purchase Plan [Member] Common Stock Including Additional Paid in Capital [Member]	Two Thousand Eighteen Dividend Reinvestment and Stock Purchase Plan [Member] Retained Earnings [Member]	Two Thousand Eighteen Dividend Reinvestment and Stock Purchase Plan [Member]	Two Thousand Twenty One Dividend Reinvestment and Stock Purchase Plan [Member] Common Stock [Member]	Two Thousand Twenty One Dividend Reinvestment and Stock Purchase Plan [Member] Common Stock Including Additional Paid in Capital [Member]	Two Thousand Twenty One Dividend Reinvestment and Stock Purchase Plan [Member] Retained Earnings [Member]	Two Thousand Twenty One Dividend Reinvestment and Stock Purchase Plan [Member]	Common Stock [Member]	Common Stock Including Additional Paid in Capital [Member]	Retained Earnings [Member]	Total
Balance (in shares) at Sep. 30, 2021									7,469,584
Balance at Sep. 30, 2021										$ 19,964	$ 63,298	$ 83,262
Net income										0	6,190	6,190
Dividends paid										0	(4,113)	(4,113)
Employee and director restricted stock vested (in shares)									132,263
Employee and director restricted stock vested										0	0	0
Repurchase of vested employee restricted stock for tax withholding (in shares)									(37,718)
Repurchase of vested employee restricted stock for tax withholding										(328)	(28)	(356)
Shares issued for auto-investments pursuant to the 2021 Dividend Reinvestment and Stock Purchase Plan (in shares)	471
Shares issued for auto-investments pursuant to the 2021 Dividend Reinvestment and Stock Purchase Plan		$ 5	$ 0	$ 5
Shares issued for dividend reinvestment pursuant to the 2021 Dividend Reinvestment and Stock Purchase Plan (in shares)	7,141
Shares issued for dividend reinvestment pursuant to the 2021 Dividend Reinvestment and Stock Purchase Plan		$ 74	$ 0	$ 74
Stock-based compensation										1,252	0	1,252
Employee restricted stock forfeiture										(16)	0	(16)
Balance (in shares) at Sep. 30, 2022									7,571,741
Balance at Sep. 30, 2022										20,951	65,347	86,298
Net income										0	4,771	4,771
Dividends paid										0	(4,166)	(4,166)
Employee and director restricted stock vested (in shares)									124,015
Employee and director restricted stock vested										0	0	0
Repurchase of vested employee restricted stock for tax withholding (in shares)									(34,192)
Repurchase of vested employee restricted stock for tax withholding										(233)	0	(233)
Shares issued for auto-investments pursuant to the 2021 Dividend Reinvestment and Stock Purchase Plan (in shares)					1,206
Shares issued for auto-investments pursuant to the 2021 Dividend Reinvestment and Stock Purchase Plan						$ 9	$ 0	$ 9
Shares issued for dividend reinvestment pursuant to the 2021 Dividend Reinvestment and Stock Purchase Plan (in shares)					8,329
Shares issued for dividend reinvestment pursuant to the 2021 Dividend Reinvestment and Stock Purchase Plan						$ 64	$ 0	$ 64
Stock-based compensation										1,026	0	1,026
Employee restricted stock forfeiture										(17)	0	(17)
Balance (in shares) at Sep. 30, 2023									7,671,099
Balance at Sep. 30, 2023										$ 21,800	$ 65,952	$ 87,752