Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2021
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	$ 218,569	$ 206,899	$ 187,630
Ending Balance	233,073	218,569	206,899
Accumulated Other Comprehensive Loss
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(717)	59	61
Other comprehensive income (loss)	(367)	(776)	(2)
Ending Balance	(1,084)	(717)	59
Available-for-sale Securities [Member] | Changes in fair value of available for sale securities
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(706)	75	87
Other comprehensive income (loss)	(369)	(781)	(12)
Ending Balance	(1,075)	(706)	75
Held-to-maturity Securities | Changes in fair value of available for sale securities
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(11)	(16)	(26)
Other comprehensive income (loss)	2	5	10
Ending Balance	$ (9)	$ (11)	$ (16)