LOANS - Composition of loans receivable and loans held-for-sale (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Loans receivable, net	$ 949,142	$ 927,413
Total
Residential 1-4 family	353,112	346,299
Residential 5+ multifamily	35,008	35,455
Construction of residential 1-4 family	12,214	11,889
Home equity lines of credit	31,907	33,798
Residential real estate	432,241	427,441
Commercial	310,436	289,795
Construction of commercial	10,922	8,466
Commercial real estate	321,358	298,261
Farm land	3,612	3,641
Vacant land	14,488	7,893
Real estate secured	771,699	737,236
Commercial and industrial	157,573	169,411
Municipal	20,964	21,914
Consumer	8,195	6,385
Loans receivable, gross	958,431	934,946
Deferred loan origination fees and costs, net	1,329	1,362
Allowance for loan losses	(10,618)	(8,895)
Loans receivable, net	949,142	927,413
Loans held-for-sale
Residential 1-4 family	$ 580	$ 332

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The reserve to cover probable credit losses related to specifically identified fixed maturity real estate loans as well as probable credit losses inherent in the remainder of that loan portfolio.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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The fair value as of the balance sheet date of firm holdings in fixed income obligations issued by state and local governments and authorities. Includes both pledged (to counterparties as collateral for financing transactions) and unpledged holdings.

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The net carrying amount as of the balance sheet date of the sum of the various components of an operative builder's inventory, including finished homes. Operative builders primarily consist of entities that develop land, construct residential homes and commercial and industrial buildings thereon, and sell them to home buyers and operators of the commercial and industrial properties.

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Total of (1) improvements, (2) held-for-sale, (3) land and land under development, (4) construction-in-process, (5) mortgage loans held-in-inventory, and (6) other real estate investments which are considered inventory due to being held for sale or disposition.

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Cost of real estate projects incurred for projects for eventual sale or transfer (condominium or time share projects, vacation clubs).

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Carrying amount as of the balance sheet date, net of valuation allowances and impairment losses, of costs of land expected to be developed in the near term plus capitalized costs of development, for purposes of selling completed units to home buyers or commercial or industrial entities..

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Represents mortgage loans held in inventory primarily for sale to others (third parties, businesses, legal entities) in the ordinary course of business.

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Amount of investment in certain other real estate investments not specifically identified elsewhere in the existing taxonomy.

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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 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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Amount, before valuation allowance, of financing receivable classified as held-for-sale.

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The balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio.

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