Revenue from Contracts with Customers (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2021
Service charges on deposits
Revenue from External Customer [Line Items]
Service charges on deposits	$ 3,824	$ 3,964	$ 3,911
ATM and debit card interchange transaction fees
Revenue from External Customer [Line Items]
Service charges on deposits	5,194	5,210	5,084
Escrow fees
Revenue from External Customer [Line Items]
Service charges on deposits	109	211	$ 290
Fee income from non-deposit investment sales
Revenue from External Customer [Line Items]
Service charges on deposits	$ 36	$ 27