LOANS RECEIVABLE AND ALLOWANCE FOR CREDIT LOSSES - Loans - Major Categories of Loans (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2023	Dec. 31, 2022	Dec. 31, 2021
Loans and Allowance for Credit Losses - Loans
Loans, net of deferred fees and costs	$ 174,796	$ 186,440
Less: Allowance for credit losses	(2,094)	(2,162)	$ (2,470)
Loans, net	$ 172,702	$ 184,278
Loans and lease receivable allowances, percentage	100.00%	100.00%
Increase (decrease) in loans and leases receivable	$ (11,600)
Percentage of increase (decrease) in loans and leases receivable	(6.28%)
Real Estate Loan
Loans and Allowance for Credit Losses - Loans
Loans, net of deferred fees and costs	$ 134,032	$ 133,323
Commercial and Industrial
Loans and Allowance for Credit Losses - Loans
Loans, net of deferred fees and costs	16,002	15,148
Consumer Loans
Loans and Allowance for Credit Losses - Loans
Loans, net of deferred fees and costs	24,762	37,969
Construction and Land \| Real Estate Loan
Loans and Allowance for Credit Losses - Loans
Loans, net of deferred fees and costs	4,145	4,499
Less: Allowance for credit losses	$ (35)	$ (44)	(5)
Loans and lease receivable allowances, percentage	2.00%	2.00%
Increase (decrease) in loans and leases receivable	$ (400)
Percentage of increase (decrease) in loans and leases receivable	(7.87%)
Farmland \| Real Estate Loan
Loans and Allowance for Credit Losses - Loans
Loans, net of deferred fees and costs	$ 327	$ 333
Less: Allowance for credit losses	(18)	(20)	(11)
Single-family Residential \| Real Estate Loan
Loans and Allowance for Credit Losses - Loans
Loans, net of deferred fees and costs	82,998	80,251
Less: Allowance for credit losses	$ (1,237)	$ (1,230)	(1,357)
Loans and lease receivable allowances, percentage	48.00%	43.00%
Increase (decrease) in loans and leases receivable	$ 2,700	$ 80,300
Percentage of increase (decrease) in loans and leases receivable	3.42%
Multi-family \| Real Estate Loan
Loans and Allowance for Credit Losses - Loans
Loans, net of deferred fees and costs	$ 5,201	5,304
Less: Allowance for credit losses	$ (97)	$ (103)	(105)
Loans and lease receivable allowances, percentage	3.00%	3.00%
Increase (decrease) in loans and leases receivable	$ (100)
Percentage of increase (decrease) in loans and leases receivable	(1.94%)
Commercial \| Real Estate Loan
Loans and Allowance for Credit Losses - Loans
Loans, net of deferred fees and costs	$ 41,361	$ 42,936
Less: Allowance for credit losses	$ (203)	$ (221)	(278)
Loans and lease receivable allowances, percentage	24.00%	23.00%
Increase (decrease) in loans and leases receivable	$ (1,600)
Percentage of increase (decrease) in loans and leases receivable	(3.67%)
Commercial and industrial \| Commercial and Industrial
Loans and Allowance for Credit Losses - Loans
Loans, net of deferred fees and costs	$ 10,032	$ 8,990
Less: Allowance for credit losses	$ (261)	$ (174)	(115)
Loans and lease receivable allowances, percentage	6.00%	5.00%
Increase (decrease) in loans and leases receivable	$ 1,000
Percentage of increase (decrease) in loans and leases receivable	(11.59%)
SBA Guaranty \| Commercial and Industrial
Loans and Allowance for Credit Losses - Loans
Loans, net of deferred fees and costs	$ 5,970	$ 6,158
Less: Allowance for credit losses	$ (22)	$ (22)	(30)
Loans and lease receivable allowances, percentage	3.00%	3.00%
Increase (decrease) in loans and leases receivable	$ (200)
Percentage of increase (decrease) in loans and leases receivable	(3.05%)
Consumer \| Consumer Loans
Loans and Allowance for Credit Losses - Loans
Loans, net of deferred fees and costs	$ 1,257	$ 1,521
Less: Allowance for credit losses	$ (24)	$ (23)	(36)
Loans and lease receivable allowances, percentage	1.00%	1.00%
Increase (decrease) in loans and leases receivable	$ (300)
Percentage of increase (decrease) in loans and leases receivable	17.33%
Automobile \| Consumer Loans
Loans and Allowance for Credit Losses - Loans
Loans, net of deferred fees and costs	$ 23,505	$ 36,448
Less: Allowance for credit losses	$ (197)	$ (325)	$ (533)
Loans and lease receivable allowances, percentage	13.00%	20.00%
Increase (decrease) in loans and leases receivable	$ (12,900)
Percentage of increase (decrease) in loans and leases receivable	(35.51%)

The increase (decrease) during the reporting period in amount of loans and leases receivables.

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The Percentage of Loans and Leases Receivable Allowance.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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