composition of loans receivable by delinquency status (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Residential 1-4 family	$ 368,801	$ 352,001
Residential 5+ multifamily	46,237	37,058
Construction of residential 1-4 family	15,429	8,814
Home equity lines of credit	24,001	27,804
Residential real estate	454,468	425,677
Commercial	314,820	310,841
Construction of commercial	47,145	31,722
Commercial real estate	361,965	342,563
Farm land	3,409	3,198
Vacant land	13,698	14,079
Real estate secured	833,540	785,517
Commercial and industrial	208,180	227,148
Municipal	18,061	21,512
Consumer	11,152	7,687
Loans receivable, gross	1,070,933	1,041,864
Loans Receivable Delinquency Status Current [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Residential 1-4 family	368,034	349,382
Residential 5+ multifamily	45,376	36,197
Construction of residential 1-4 family	15,429	8,814
Home equity lines of credit	23,831	27,522
Residential real estate	452,670	421,915
Commercial	314,342	307,927
Construction of commercial	47,145	31,722
Commercial real estate	361,487	339,649
Farm land	3,279	2,594
Vacant land	13,663	14,079
Real estate secured	831,099	778,237
Commercial and industrial	207,792	224,496
Municipal	18,061	21,512
Consumer	11,108	7,677
Loans receivable, gross	1,068,060	1,031,922
Loans Receivable Delinquency Status Period Two [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Residential 1-4 family	167	1,419
Residential 5+ multifamily
Construction of residential 1-4 family
Home equity lines of credit	105	157
Residential real estate	272	1,576
Commercial	200	1,855
Construction of commercial
Commercial real estate	200	1,855
Farm land	130	154
Vacant land	35
Real estate secured	637	3,585
Commercial and industrial	289	2,148
Municipal
Consumer	4	10
Loans receivable, gross	930	5,743
Loans Receivable Delinquency Status Period Three [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Residential 1-4 family	84	308
Residential 5+ multifamily
Construction of residential 1-4 family
Home equity lines of credit	14	9
Residential real estate	98	317
Commercial	24	530
Construction of commercial
Commercial real estate	24	530
Farm land		450
Vacant land
Real estate secured	122	1,297
Commercial and industrial	53	457
Municipal
Consumer	40
Loans receivable, gross	215	1,754
Loans Receivable Delinquency Status Period Four [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Residential 1-4 family	442	673
Residential 5+ multifamily
Construction of residential 1-4 family
Home equity lines of credit
Residential real estate	442	673
Commercial		95
Construction of commercial
Commercial real estate		95
Farm land
Vacant land
Real estate secured	442	768
Commercial and industrial		1
Municipal
Consumer
Loans receivable, gross	442	769
Loans Receivable Delinquency Status Period Five [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Residential 1-4 family	74	219
Residential 5+ multifamily	861	861
Construction of residential 1-4 family
Home equity lines of credit	51	116
Residential real estate	986	1,196
Commercial	254	434
Construction of commercial
Commercial real estate	254	434
Farm land
Vacant land
Real estate secured	1,240	1,630
Commercial and industrial	46	46
Municipal
Consumer
Loans receivable, gross	1,286	1,676
Loans Receivable Delinquency Status Period Six [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Residential 1-4 family	767	2,619
Residential 5+ multifamily	861	861
Construction of residential 1-4 family
Home equity lines of credit	170	282
Residential real estate	1,798	3,762
Commercial	478	2,914
Construction of commercial
Commercial real estate	478	2,914
Farm land	130	604
Vacant land	35
Real estate secured	2,441	7,280
Commercial and industrial	388	2,652
Municipal
Consumer	44	10
Loans receivable, gross	2,873	9,942
Loans Receivable Delinquency Accrual [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
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	11	12
Municipal
Consumer
Loans receivable, gross	11	12
Loans Receivable Delinquency Non Accrual [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Residential 1-4 family	1,235	1,508
Residential 5+ multifamily	861	861
Construction of residential 1-4 family
Home equity lines of credit	86	154
Residential real estate	2,182	2,523
Commercial	1,954	2,544
Construction of commercial
Commercial real estate	1,954	2,544
Farm land	576	158
Vacant land	35	37
Real estate secured	4,747	5,262
Commercial and industrial	243	374
Municipal
Consumer
Loans receivable, gross	$ 4,990	$ 5,636

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