LOANS - Composition of loans receivable by risk rating grade (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Pass
Residential 1-4 family	$ 344,792	$ 337,302
Residential 5+ multifamily	33,180	33,619
Construction of residential 1-4 family	12,214	11,889
Home equity lines of credit	31,313	33,381
Residential real estate	421,499	416,191
Commercial	291,486	271,708
Construction of commercial	10,684	8,225
Commercial real estate	302,170	279,933
Farm land	1,918	1,934
Vacant land	14,390	7,834
Real estate secured	739,977	705,892
Commercial and industrial	155,326	167,458
Municipal	20,964	21,914
Consumer	8,157	6,344
Loans receivable, gross	924,424	901,608
Special mention
Residential 1-4 family	4,191	4,278
Residential 5+ multifamily	98	99
Construction of residential 1-4 family
Home equity lines of credit	387	312
Residential real estate	4,676	4,689
Commercial	4,687	10,964
Construction of commercial
Commercial real estate	4,687	10,964
Farm land
Vacant land	57	59
Real estate secured	9,420	15,712
Commercial and industrial	473	443
Municipal
Consumer	4	3
Loans receivable, gross	9,897	16,158
Substandard
Residential 1-4 family	4,129	4,719
Residential 5+ multifamily	1,730	1,737
Construction of residential 1-4 family
Home equity lines of credit	207	105
Residential real estate	6,066	6,561
Commercial	14,192	7,052
Construction of commercial	238	241
Commercial real estate	14,430	7,293
Farm land	1,694	1,707
Vacant land	41
Real estate secured	22,231	15,561
Commercial and industrial	1,774	1,510
Municipal
Consumer	34	38
Loans receivable, gross	24,039	17,109
Doubtful
Residential 1-4 family
Residential 5+ multifamily
Construction of residential 1-4 family
Home equity lines of credit
Residential real estate
Commercial	71	71
Construction of commercial
Commercial real estate	71	71
Farm land
Vacant land
Real estate secured	71	71
Commercial and industrial
Municipal
Consumer
Loans receivable, gross	71	71
Loss
Residential 1-4 family
Residential 5+ multifamily
Construction of residential 1-4 family
Home equity lines of credit
Residential real estate
Commercial
Construction of commercial
Commercial real estate
Farm land
Vacant land
Real estate secured
Commercial and industrial
Municipal
Consumer
Loans receivable, gross
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

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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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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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