LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES - Major Categories of Loans (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2019	Dec. 31, 2018
Schedule of Available-for-sale Securities [Line Items]
Loans, net of deferred fees and costs	$ 283,889	$ 299,120
Less: Allowance for loan losses	(2,307)	(2,541)
Loans, net	$ 281,582	$ 296,579
Loans and lease receivable allowances, percentage	100.00%	100.00%
Increase (decrease) in loans and leases receivable	$ 15,000
Percentage of increase (decrease) in loans and leases receivable	5.06%
Consumer
Schedule of Available-for-sale Securities [Line Items]
Loans, net of deferred fees and costs	$ 12,369	$ 13,071
Loans and lease receivable allowances, percentage	4.00%	4.00%
Increase (decrease) in loans and leases receivable	$ 700
Percentage of increase (decrease) in loans and leases receivable	5.37%
Residential Real estate
Schedule of Available-for-sale Securities [Line Items]
Loans, net of deferred fees and costs	$ 80,211	$ 82,637
Loans and lease receivable allowances, percentage	28.00%	28.00%
Increase (decrease) in loans and leases receivable	$ 2,400	$ 82,600
Percentage of increase (decrease) in loans and leases receivable	2.94%
Indirect
Schedule of Available-for-sale Securities [Line Items]
Loans, net of deferred fees and costs	$ 106,088	$ 116,698
Loans and lease receivable allowances, percentage	38.00%	39.00%
Increase (decrease) in loans and leases receivable	$ 10,600	$ 116,700
Percentage of increase (decrease) in loans and leases receivable	9.09%
Commercial
Schedule of Available-for-sale Securities [Line Items]
Loans, net of deferred fees and costs	$ 11,350	$ 14,284
Loans and lease receivable allowances, percentage	4.00%	5.00%
Increase (decrease) in loans and leases receivable	$ 2,900
Percentage of increase (decrease) in loans and leases receivable	20.54%
Construction
Schedule of Available-for-sale Securities [Line Items]
Loans, net of deferred fees and costs	$ 3,161	$ 2,317
Loans and lease receivable allowances, percentage	1.00%	1.00%
Increase (decrease) in loans and leases receivable	$ 800
Percentage of increase (decrease) in loans and leases receivable	36.40%
Commercial Real Estate
Schedule of Available-for-sale Securities [Line Items]
Loans, net of deferred fees and costs	$ 70,710	$ 70,113
Loans and lease receivable allowances, percentage	25.00%	23.00%
Increase (decrease) in loans and leases receivable	$ 600
Percentage of increase (decrease) in loans and leases receivable	0.85%

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

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The percentage of increase (decrease) in loans and leases receivable.

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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 of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. 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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