composition of loans receivable by risk rating grade (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Residential 1-4 family	$ 342,243	$ 337,302
Residential 5+ multifamily	35,272	33,619
Construction of residential 1-4 family	8,814	11,889
Home equity lines of credit	27,393	33,381
Residential real estate	413,722	416,191
Commercial	276,866	271,708
Construction of commercial	31,493	8,225
Commercial real estate	308,359	279,933
Farm land	1,612	1,934
Vacant land	13,992	7,834
Real estate secured	737,685	705,892
Commercial and industrial	224,906	167,458
Municipal	21,512	21,914
Consumer	7,660	6,344
Loans receivable, gross	991,763	901,608
Special Mention [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Residential 1-4 family	5,615	4,278
Residential 5+ multifamily	90	99
Construction of residential 1-4 family
Home equity lines of credit	257	312
Residential real estate	5,962	4,689
Commercial	15,565	10,964
Construction of commercial
Commercial real estate	15,565	10,964
Farm land
Vacant land	50	59
Real estate secured	21,577	15,712
Commercial and industrial	1,271	443
Municipal
Consumer		3
Loans receivable, gross	22,848	16,158
Substandard [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Residential 1-4 family	4,143	4,719
Residential 5+ multifamily	1,696	1,737
Construction of residential 1-4 family
Home equity lines of credit	154	105
Residential real estate	5,993	6,561
Commercial	18,410	7,052
Construction of commercial	229	241
Commercial real estate	18,639	7,293
Farm land	1,586	1,707
Vacant land	37
Real estate secured	26,255	15,561
Commercial and industrial	632	1,510
Municipal
Consumer	27	38
Loans receivable, gross	26,914	17,109
Doubtful [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Residential 1-4 family
Residential 5+ multifamily
Construction of residential 1-4 family
Home equity lines of credit
Residential real estate
Commercial		71
Construction of commercial
Commercial real estate		71
Farm land
Vacant land
Real estate secured		71
Commercial and industrial	339
Municipal
Consumer
Loans receivable, gross	339	71
Unlikely to be Collected Financing Receivable [Member]
Financing Receivable, Credit Quality Indicator [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
Municipal
Consumer
Loans receivable, gross
Nonperforming Financial Instruments [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Residential 1-4 family	352,001	346,299
Residential 5+ multifamily	37,058	35,455
Construction of residential 1-4 family	8,814	11,889
Home equity lines of credit	27,804	33,798
Residential real estate	425,677	427,441
Commercial	310,841	289,795
Construction of commercial	31,722	8,466
Commercial real estate	342,563	298,261
Farm land	3,198	3,641
Vacant land	14,079	7,893
Real estate secured	785,517	737,236
Commercial and industrial	227,148	169,411
Municipal	21,512	21,914
Consumer	7,687	6,385
Loans receivable, gross	$ 1,041,864	$ 934,946

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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 before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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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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