Borrowings (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Contractual Maturities of FHLB Advances
2023/2022	$ 11,860	$ 4,000
2024/2023	18,860	12,040
2025/2024	7,080	18,860
2025		7,080
FHLB advances	$ 92,800	$ 41,980
Weighted Average Interest Rates of FHLB Advances
2023/2022	2.23%	2.02%
2024/2023	0.98%	2.23%
2025/2024	0.58%	0.98%
2025		0.58%
Weighted average rate	2.48%	1.37%
Borrowings
Additional eligible borrowings from FHLB	$ 183,600
Short-term Debt	101,752	$ 159,642
Term Advances
Contractual Maturities of FHLB Advances
FHLB advances	$ 37,800	$ 41,980
Weighted Average Interest Rates of FHLB Advances
Weighted average rate	1.30%	1.37%
Overnight Borrowings
Contractual Maturities of FHLB Advances
FHLB advances	$ 55,000	$ 0
Weighted Average Interest Rates of FHLB Advances
Weighted average rate	3.29%
Unsecured Debt
Borrowings
Line of credit available for borrowing	$ 65,000
Borrowings outstanding	$ 0	$ 0
Minimum
Weighted Average Interest Rates of FHLB Advances
2023/2022	0.37%	2.01%
2024/2023	0.39%	0.37%
2025/2024	0.56%	0.39%
2025		0.56%
Maximum
Weighted Average Interest Rates of FHLB Advances
2023/2022	2.96%	2.05%
2024/2023	2.53%	2.96%
2025/2024	0.59%	2.53%
2025		0.59%
PPPLF
Borrowings
Short-term Debt	$ 9,000	$ 117,700
Borrowing rate of interest	0.35%
PPP Loans | Minimum
Borrowings
Debt instrument, term	2 years
PPP Loans | Maximum
Borrowings
Debt instrument, term	5 years
Residential and Commercial Mortgage Loans
Borrowings
Amount of collateral pledged	$ 822,200	$ 432,700