Consolidated Statements of Shareholders' Equity - USD ($) $ in Thousands	Total		Stock Options	Common Stock	Common Stock Stock Options	Retained Earnings	Accumulated Other Compre-hensive Income (Loss)
Balance at beginning of period (in shares) at Sep. 30, 2021				8,355,469
Balance at beginning of period at Sep. 30, 2021	$ 206,899			$ 42,673		$ 164,167	$ 59	[1]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	10,812					10,812
Other comprehensive loss	(166)						(166)
Repurchase of common stock (in shares)				(77,113)
Repurchase of common stock	$ (2,149)			$ (2,149)
Exercise of stock options (in shares)	27,470			27,470
Exercise of stock options	$ 332			$ 332
Common stock dividends	(3,591)					(3,591)
Stock option compensation expense			$ 132		$ 132
Balance at end of period (in shares) at Mar. 31, 2022				8,305,826
Balance at end of period at Mar. 31, 2022	212,269			$ 40,988		171,388	(107)	[1]
Balance at beginning of period (in shares) at Dec. 31, 2021				8,348,821
Balance at beginning of period at Dec. 31, 2021	210,375			$ 42,436		167,897	42	[1]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	5,327					5,327
Other comprehensive loss	(149)						(149)
Repurchase of common stock (in shares)				(61,565)
Repurchase of common stock	(1,716)			$ (1,716)
Exercise of stock options (in shares)				18,570
Exercise of stock options	202			$ 202
Common stock dividends	(1,836)					(1,836)
Stock option compensation expense			66		66
Balance at end of period (in shares) at Mar. 31, 2022				8,305,826
Balance at end of period at Mar. 31, 2022	212,269			$ 40,988		171,388	(107)	[1]
Balance at beginning of period (in shares) at Sep. 30, 2022				8,221,952
Balance at beginning of period at Sep. 30, 2022	218,569	[2]		$ 38,751		180,535	(717)	[1]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	14,169					14,169
Other comprehensive loss	222						222
Repurchase of common stock (in shares)				(44,833)
Repurchase of common stock	$ (1,445)			$ (1,445)
Exercise of stock options (in shares)	26,055			26,055
Exercise of stock options	$ 517			$ 517
Common stock dividends	(4,527)					(4,527)
Stock option compensation expense			156		156
Balance at end of period (in shares) at Mar. 31, 2023				8,203,174
Balance at end of period at Mar. 31, 2023	227,661			$ 37,979		190,177	(495)	[1]
Balance at beginning of period (in shares) at Dec. 31, 2022				8,231,197
Balance at beginning of period at Dec. 31, 2022	223,549			$ 38,878		185,406	(735)	[1]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	6,663					6,663
Other comprehensive loss	240						240
Repurchase of common stock (in shares)				(34,263)
Repurchase of common stock	(1,098)			$ (1,098)
Exercise of stock options (in shares)				6,240
Exercise of stock options	121			$ 121
Common stock dividends	(1,892)					(1,892)
Stock option compensation expense			$ 78		$ 78
Balance at end of period (in shares) at Mar. 31, 2023				8,203,174
Balance at end of period at Mar. 31, 2023	$ 227,661			$ 37,979		$ 190,177	$ (495)	[1]

[1] All amounts are net of income taxes.

[2] Derived from audited consolidated financial statements.