Consolidated Statements of Shareholders' Equity - USD ($) $ in Thousands	Total	Impact of Adopting CECL (ASU 2016-13)	Common Stock	Retained Earnings	Accumulated Other Comprehensive Loss
Beginning Balance (in shares) at Sep. 30, 2021			8,355,469
Beginning Balance at Sep. 30, 2021	$ 206,899		$ 42,673	$ 164,167	$ 59
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	23,600			23,600
Other comprehensive loss	(776)				(776)
Repurchase of common stock (in shares)			(170,237)
Repurchase of common stock	$ (4,583)		$ (4,583)
Exercise of stock options (in shares)	36,720		36,720
Exercise of stock options	$ 415		$ 415
Common stock dividends	(7,232)			(7,232)
Stock based compensation expense	246		246
Ending Balance at Sep. 30, 2022	218,569		$ 38,751	180,535	(717)
Ending Balance (in shares) at Sep. 30, 2022			8,221,952
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	27,118			27,118
Other comprehensive loss	(367)				(367)
Repurchase of common stock (in shares)			(185,399)
Repurchase of common stock	$ (4,998)		$ (4,998)
Restricted stock grants (in shares)	26,150
Exercise of stock options (in shares)	42,635		42,635
Exercise of stock options	$ 698		$ 698
Common stock dividends	(8,267)			(8,267)
Stock based compensation expense	320		320
Ending Balance at Sep. 30, 2023	233,073	$ (488)	$ 34,771	199,386	(1,084)
Ending Balance (in shares) at Sep. 30, 2023			8,105,338
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	24,283			24,283
Other comprehensive loss	1,104				1,104
Repurchase of common stock (in shares)			(218,976)
Repurchase of common stock	$ (5,958)		$ (5,958)
Restricted stock grants (in shares)	28,615
Exercise of stock options (in shares)	45,150		45,150
Exercise of stock options	$ 659		$ 659
Common stock dividends	(7,650)			(7,650)
Stock based compensation expense	390		390
Ending Balance at Sep. 30, 2024	$ 245,413		$ 29,862	$ 215,531	$ 20
Ending Balance (in shares) at Sep. 30, 2024			7,960,127