Consolidated Statements of Income - USD ($)	12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2022
Interest and dividend income
Loans receivable and loans held for sale	$ 77,430,000	$ 63,154,000	$ 51,324,000
Investment securities	9,129,000	9,384,000	3,488,000
Dividends from mutual funds, FHLB stock and other investments	361,000	270,000	120,000
Interest-bearing deposits in banks and CDs	7,905,000	7,143,000	3,576,000
Total interest and dividend income	94,825,000	79,951,000	58,508,000
Interest expense
Deposits	29,659,000	11,302,000	2,657,000
FHLB borrowings	999,000	290,000	17,000
Total interest expense	30,658,000	11,592,000	2,674,000
Net interest income	64,167,000	68,359,000	55,834,000
Provision for (recapture of) credit losses
Provision for credit losses - loans	1,254,000	2,132,000	270,000
Recapture of credit losses - investment securities	(32,000)	0	0
Recapture of credit losses - unfunded commitments	(71,000)	0	0
Total provision for credit losses - net	1,151,000	2,132,000	270,000
Net interest income after provision for (recapture of) credit losses	63,016,000	66,227,000	55,564,000
Non-interest income
Net recoveries on investment securities	12,000	9,000	22,000
Gain on sales of investment securities, net	0	95,000	0
BOLI net earnings	645,000	706,000	613,000
Gain on sales of loans, net	322,000	244,000	1,510,000
Valuation recovery on loan servicing rights, net	0	0	119,000
Other, net	958,000	959,000	975,000
Total non-interest income, net	11,136,000	11,140,000	12,624,000
Non-interest expense
Salaries and employee benefits	23,730,000	23,562,000	20,816,000
Premises and equipment	3,998,000	3,915,000	3,736,000
(Gain) loss on sales/dispositions of premises and equipment, net	(2,000)	(19,000)	13,000
Advertising	761,000	786,000	695,000
Other real estate owned ("OREO") and other repossessed assets, net	5,000	1,000	(17,000)
ATM and debit card interchange transaction fees	2,384,000	1,987,000	1,943,000
Postage and courier	538,000	532,000	577,000
Amortization of CDI	226,000	271,000	316,000
State and local taxes	1,322,000	1,219,000	1,062,000
Professional fees	1,317,000	2,078,000	1,747,000
Federal Deposit Insurance Corporation ("FDIC") insurance	833,000	711,000	506,000
Loan administration and foreclosure	521,000	503,000	508,000
Technology and communications	4,264,000	3,545,000	2,719,000
Deposit operations	1,540,000	1,368,000	1,235,000
Other	2,309,000	2,914,000	2,770,000
Total non-interest expense, net	43,746,000	43,373,000	38,626,000
Income before income taxes and equity in undistributed     income of Bank	30,406,000	33,994,000	29,562,000
Provision for income taxes	6,123,000	6,876,000	5,962,000
Net income	$ 24,283,000	$ 27,118,000	$ 23,600,000
Net income per common share
Basic (in dollars per share)	$ 3.02	$ 3.32	$ 2.84
Diluted (in dollars per share)	$ 3.01	$ 3.29	$ 2.82
Service charges on deposits
Non-interest income
Service charges on deposits	$ 4,062,000	$ 3,824,000	$ 3,964,000
ATM and debit card interchange transaction fees
Non-interest income
Service charges on deposits	5,066,000	5,194,000	5,210,000
Escrow fees
Non-interest income
Service charges on deposits	71,000	109,000	$ 211,000
Fee income from non-deposit investment sales
Non-interest income
Service charges on deposits	$ 12,000	$ 36,000