LOANS - Composition of loans receivable by risk rating grade (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Pass
Residential 1-4 family	$ 337,510	$ 307,240
Residential 5+ multifamily	28,925	16,129
Construction of residential 1-4 family	13,125	11,197
Home equity lines of credit	34,039	32,891
Residential real estate	413,599	367,457
Commercial	266,678	232,492
Construction of commercial	10,324	9,622
Commercial real estate	277,002	242,114
Farm land	3,998	4,024
Vacant land	8,655	7,806
Real estate secured	703,254	621,401
Commercial and industrial	147,897	129,219
Municipal	18,388	17,494
Consumer	4,572	4,744
Loans receivable, gross	874,111	772,858
Special mention
Residential 1-4 family	4,330	6,452
Residential 5+ multifamily	787	957
Construction of residential 1-4 family
Home equity lines of credit	311	710
Residential real estate	5,428	8,119
Commercial	3,195	4,456
Construction of commercial
Commercial real estate	3,195	4,456
Farm land
Vacant land	71	77
Real estate secured	8,694	12,652
Commercial and industrial	1,850	2,536
Municipal
Consumer	33	50
Loans receivable, gross	10,577	15,238
Substandard
Residential 1-4 family	6,378	3,947
Residential 5+ multifamily	1,003	1,022
Construction of residential 1-4 family
Home equity lines of credit	513	170
Residential real estate	7,894	5,139
Commercial	10,767	12,363
Construction of commercial	361	366
Commercial real estate	11,128	12,729
Farm land	224	250
Vacant land
Real estate secured	19,246	18,118
Commercial and industrial	968	976
Municipal
Consumer
Loans receivable, gross	20,214	19,094
Doubtful
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
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	348,218	317,639
Residential 5+ multifamily	30,715	18,108
Construction of residential 1-4 family	13,125	11,197
Home equity lines of credit	34,863	33,771
Residential real estate	426,921	380,715
Commercial	280,640	249,311
Construction of commercial	10,685	9,988
Commercial real estate	291,325	259,299
Farm land	4,222	4,274
Vacant land	8,726	7,883
Real estate secured	731,194	652,171
Commercial and industrial	150,715	132,731
Municipal	18,388	17,494
Consumer	4,605	4,794
Loans receivable, gross	$ 904,902	$ 807,190