FAIR VALUE MEASUREMENTS - Estimated fair values of financial instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Sep. 30, 2023
FAIR VALUE MEASUREMENTS
Cash and due from banks	$ 8,357	$ 9,306
Interest bearing deposits with banks	1,756	1,101
Time deposits in other financial institutions	30,321	24,531
Available for sale debt securities		46,624
Carrying Value
FAIR VALUE MEASUREMENTS
Cash and due from banks	8,357	9,306
Interest bearing deposits with banks	1,756	1,101
Time deposits in other financial institutions	245	484
Available for sale debt securities	47,902	46,624
Acquired loans	29,614	32,174
Portfolio loans, net of deferred fees	94,108	93,253
Investment in restricted stock	1,045	1,471
Accrued interest receivable	679	630
Interest rate swap derivative	68	250
Financial Liabilities
Deposits	162,767	158,778
Accrued interest payable	13	67
Fair Value
FAIR VALUE MEASUREMENTS
Cash and due from banks	8,357	9,306
Interest bearing deposits with banks	1,756	1,101
Time deposits in other financial institutions	245	484
Available for sale debt securities	47,902	46,624
Acquired loans	29,614	32,174
Portfolio loans, net of deferred fees	78,137	69,608
Investment in restricted stock	1,045	1,471
Accrued interest receivable	679	630
Interest rate swap derivative	68	250
Financial Liabilities
Deposits	121,591	119,212
Accrued interest payable	$ 13	$ 67

Fair value portion of accrued interest payable.

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Fair value portion of accrued interest receivable.

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Fair value portion of acquired loans.

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Fair value portion of investment in restricted stock.

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Fair value portion of portfolio loans, net of deferred fees.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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For banks and other depository institutions: Includes cash on hand (currency and coin), cash items in process of collection, noninterest bearing deposits due from other financial institutions (including corporate credit unions), and noninterest bearing balances with the Federal Reserve Banks, Federal Home Loan Banks and central banks.

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Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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For banks and other depository institutions (including Federal Reserve Banks, if applicable): Interest-bearing deposits in other financial institutions for relatively short periods of time including, for example, certificates of deposits, which are presented separately from cash on the balance sheet.

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Fair value as of the balance sheet date of interest rate derivative assets, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as assets.

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Amount of time deposit liabilities, including certificates of deposit.

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