LOANS - Composition of loans receivable and allowance for loan losses (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Totals	$ 911,188	$ 909,279
Collectively evaluated Loans
Residential 1-4 family	329,513	340,946
Residential 5+ multifamily	36,048	34,835
Construction of residential 1-4 family	11,272	12,041
Home equity lines credit	34,570	33,975
Residential real estate	411,403	421,797
Commercial	284,272	279,389
Construction of commercial	11,010	8,622
Commercial real estate	295,282	288,011
Farm land	3,943	3,969
Vacant land	7,977	8,132
Real estate secured	718,605	721,909
Commercial and industrial	167,005	162,404
Municipal	15,702	14,344
Consumer	4,377	4,512
Unallocated allowance
Totals	905,689	903,169
Collectively evaluated Allowance
Residential 1-4 family	1,867	2,042
Residential 5+ multifamily	466	413
Construction of residential 1-4 family	77	83
Home equity lines credit	207	213
Residential real estate	2,617	2,751
Commercial	3,617	2,907
Construction of commercial	129	106
Commercial real estate	3,746	3,013
Farm land	47	33
Vacant land	87	98
Real estate secured	6,497	5,895
Commercial and industrial	1,233	1,158
Municipal	14	12
Consumer	51	56
Unallocated allowance	638	438
Totals	8,433	7,559
Individually evaluated Loans
Residential 1-4 family	4,844	4,916
Residential 5+ multifamily	1,379	1,675
Construction of residential 1-4 family
Home equity lines credit	452	458
Residential real estate	6,675	7,049
Commercial	4,995	4,210
Construction of commercial	349	354
Commercial real estate	5,344	4,564
Farm land	212	216
Vacant land	187	190
Real estate secured	12,418	12,019
Commercial and industrial	498	501
Municipal
Consumer
Unallocated allowance
Totals	12,916	12,520
Individually evaluated Allowance
Residential 1-4 family	113	107
Residential 5+ multifamily
Construction of residential 1-4 family
Home equity lines credit	2	6
Residential real estate	115	113
Commercial	186	141
Construction of commercial	14	16
Commercial real estate	200	157
Farm land
Vacant land	2	2
Real estate secured	317	272
Commercial and industrial
Municipal
Consumer
Unallocated allowance
Totals	317	272
Total portfolio Loans
Residential 1-4 family	334,357	345,862
Residential 5+ multifamily	37,427	36,510
Construction of residential 1-4 family	11,272	12,041
Home equity lines credit	35,022	34,433
Residential real estate	418,078	428,846
Commercial	289,267	283,599
Construction of commercial	11,359	8,976
Commercial real estate	300,626	292,575
Farm land	4,155	4,185
Vacant land	8,164	8,322
Real estate secured	731,023	733,928
Commercial and industrial	167,503	162,905
Municipal	15,702	14,344
Consumer	4,377	4,512
Unallocated allowance
Totals	918,605	915,689
Total portfolio Allowance
Residential 1-4 family	1,980	2,149
Residential 5+ multifamily	466	413
Construction of residential 1-4 family	77	83
Home equity lines credit	209	219
Residential real estate	2,732	2,864
Commercial	3,803	3,048
Construction of commercial	143	122
Commercial real estate	3,946	3,170
Farm land	47	33
Vacant land	89	100
Real estate secured	6,814	6,167
Commercial and industrial	1,233	1,158
Municipal	14	12
Consumer	51	56
Unallocated allowance	638	438
Totals	$ 8,750	$ 7,831

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Amount of valuation allowance for receivables classified as other, due within one year or the normal operating cycle, if longer.

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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 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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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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