composition of loans receivable by delinquency status (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Loans Receivable Delinquency Status Current [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Residential 1-4 family	$ 349,382	$ 344,085
Residential 5+ multifamily	36,197	34,594
Construction of residential 1-4 family	8,814	11,889
Home equity lines of credit	27,522	33,522
Residential real estate	421,915	424,090
Commercial	307,927	289,103
Construction of commercial	31,722	8,466
Commercial real estate	339,649	297,569
Farm land	2,594	3,461
Vacant land	14,079	7,852
Real estate secured	778,237	732,972
Commercial and industrial	224,496	169,262
Municipal	21,512	21,914
Consumer	7,677	6,382
Loans receivable, gross	1,031,922	930,530
Loans Receivable Delinquency Status Period Two [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Residential 1-4 family	1,419	971
Residential 5+ multifamily
Construction of residential 1-4 family
Home equity lines of credit	157	152
Residential real estate	1,576	1,123
Commercial	1,855	336
Construction of commercial
Commercial real estate	1,855	336
Farm land	154	180
Vacant land
Real estate secured	3,585	1,639
Commercial and industrial	2,148	2
Municipal
Consumer	10
Loans receivable, gross	5,743	1,641
Loans Receivable Delinquency Status Period Three [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Residential 1-4 family	308	351
Residential 5+ multifamily
Construction of residential 1-4 family
Home equity lines of credit	9	46
Residential real estate	317	397
Commercial	530	141
Construction of commercial
Commercial real estate	530	141
Farm land	450
Vacant land		41
Real estate secured	1,297	579
Commercial and industrial	457	146
Municipal
Consumer		1
Loans receivable, gross	1,754	726
Loans Receivable Delinquency Status Period Four [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Residential 1-4 family	673	200
Residential 5+ multifamily
Construction of residential 1-4 family
Home equity lines of credit
Residential real estate	673	200
Commercial	95	71
Construction of commercial
Commercial real estate	95	71
Farm land
Vacant land
Real estate secured	768	271
Commercial and industrial	1	1
Municipal
Consumer		2
Loans receivable, gross	769	274
Loans Receivable Delinquency Status Period Five [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Residential 1-4 family	219	692
Residential 5+ multifamily	861	861
Construction of residential 1-4 family
Home equity lines of credit	116	78
Residential real estate	1,196	1,631
Commercial	434	144
Construction of commercial
Commercial real estate	434	144
Farm land
Vacant land
Real estate secured	1,630	1,775
Commercial and industrial	46
Municipal
Consumer
Loans receivable, gross	1,676	1,775
Loans Receivable Delinquency Status Period Six [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Residential 1-4 family	2,619	2,214
Residential 5+ multifamily	861	861
Construction of residential 1-4 family
Home equity lines of credit	282	276
Residential real estate	3,762	3,351
Commercial	2,914	692
Construction of commercial
Commercial real estate	2,914	692
Farm land	604	180
Vacant land		41
Real estate secured	7,280	4,264
Commercial and industrial	2,652	149
Municipal
Consumer	10	3
Loans receivable, gross	9,942	4,416
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	12	1
Municipal
Consumer		2
Loans receivable, gross	12	3
Loans Receivable Delinquency Non Accrual [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Residential 1-4 family	1,508	1,551
Residential 5+ multifamily	861	861
Construction of residential 1-4 family
Home equity lines of credit	154	105
Residential real estate	2,523	2,517
Commercial	2,544	914
Construction of commercial
Commercial real estate	2,544	914
Farm land	158	186
Vacant land	37
Real estate secured	5,262	3,617
Commercial and industrial	374
Municipal
Consumer
Loans receivable, gross	$ 5,636	$ 3,617

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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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