composition of loans receivable by delinquency status (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Loans Receivable Delinquency Status Current [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Residential 1-4 family	$ 341,636	$ 349,382
Residential 5+ multifamily	36,928	36,197
Construction of residential 1-4 family	10,435	8,814
Home equity lines of credit	26,119	27,522
Residential real estate	415,118	421,915
Commercial	306,233	307,927
Construction of commercial	34,312	31,722
Commercial real estate	340,545	339,649
Farm land	3,005	2,594
Vacant land	13,191	14,079
Real estate secured	771,859	778,237
Commercial and industrial	249,042	224,496
Municipal	21,495	21,512
Consumer	8,615	7,677
Loans receivable, gross	1,051,011	1,031,922
Loans Receivable Delinquency Status Period Two [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Residential 1-4 family	1,806	1,419
Residential 5+ multifamily
Construction of residential 1-4 family
Home equity lines of credit	8	157
Residential real estate	1,814	1,576
Commercial	293	1,855
Construction of commercial
Commercial real estate	293	1,855
Farm land	4	154
Vacant land
Real estate secured	2,111	3,585
Commercial and industrial	266	2,148
Municipal
Consumer	2	10
Loans receivable, gross	2,379	5,743
Loans Receivable Delinquency Status Period Three [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Residential 1-4 family		308
Residential 5+ multifamily
Construction of residential 1-4 family
Home equity lines of credit		9
Residential real estate		317
Commercial		530
Construction of commercial
Commercial real estate		530
Farm land	147	450
Vacant land
Real estate secured	147	1,297
Commercial and industrial		457
Municipal
Consumer
Loans receivable, gross	147	1,754
Loans Receivable Delinquency Status Period Four [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Residential 1-4 family	372	673
Residential 5+ multifamily
Construction of residential 1-4 family
Home equity lines of credit	9
Residential real estate	381	673
Commercial	209	95
Construction of commercial
Commercial real estate	209	95
Farm land	450
Vacant land	37
Real estate secured	1,077	768
Commercial and industrial	2	1
Municipal
Consumer
Loans receivable, gross	1,079	769
Loans Receivable Delinquency Status Period Five [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Residential 1-4 family	713	219
Residential 5+ multifamily	861	861
Construction of residential 1-4 family
Home equity lines of credit	104	116
Residential real estate	1,678	1,196
Commercial	95	434
Construction of commercial
Commercial real estate	95	434
Farm land
Vacant land
Real estate secured	1,773	1,630
Commercial and industrial	47	46
Municipal
Consumer
Loans receivable, gross	1,820	1,676
Loans Receivable Delinquency Status Period Six [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Residential 1-4 family	2,891	2,619
Residential 5+ multifamily	861	861
Construction of residential 1-4 family
Home equity lines of credit	121	282
Residential real estate	3,873	3,762
Commercial	597	2,914
Construction of commercial
Commercial real estate	597	2,914
Farm land	601	604
Vacant land	37
Real estate secured	5,108	7,280
Commercial and industrial	315	2,652
Municipal
Consumer	2	10
Loans receivable, gross	5,425	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	40
Construction of commercial
Commercial real estate	40
Farm land	450
Vacant land
Real estate secured	490
Commercial and industrial	14	12
Municipal
Consumer
Loans receivable, gross	504	12
Loans Receivable Delinquency Non Accrual [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Residential 1-4 family	1,358	1,508
Residential 5+ multifamily	861	861
Construction of residential 1-4 family
Home equity lines of credit	237	154
Residential real estate	2,456	2,523
Commercial	2,233	2,544
Construction of commercial
Commercial real estate	2,233	2,544
Farm land	151	158
Vacant land	37	37
Real estate secured	4,877	5,262
Commercial and industrial	325	374
Municipal
Consumer
Loans receivable, gross	$ 5,202	$ 5,636

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