composition of loans receivable (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans receivable, net	$ 1,041,185	$ 1,027,738
Loans Receivable [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Residential 1-4 family	344,527	352,001
Residential 5+ multifamily	37,789	37,058
Construction of residential 1-4 family	10,435	8,814
Home equity lines of credit	26,240	27,804
Residential real estate	418,991	425,677
Commercial	306,830	310,841
Construction of commercial	34,312	31,722
Commercial real estate	341,142	342,563
Farm land	3,606	3,198
Vacant land	13,228	14,079
Real estate secured	776,967	785,517
Commercial and industrial	249,357	227,148
Municipal	21,495	21,512
Consumer	8,617	7,687
Loans receivable, gross	1,056,436	1,041,864
Deferred loan origination (fees) and costs, net	(1,365)	(372)
Allowance for loan losses	(13,886)	(13,754)
Loans receivable, net	1,041,185	1,027,738
Loans held-for-sale
Residential 1-4 family	$ 2,313	$ 2,735

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The reserve to cover probable credit losses related to specifically identified fixed maturity real estate loans as well as probable credit losses inherent in the remainder of that loan portfolio.

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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 of investment in certain other real estate investments not specifically identified elsewhere in the existing taxonomy.

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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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Amount after allowance and 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 and loans held for sale.

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Amount, before valuation allowance, of financing receivable classified as held-for-sale.

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The balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio.

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Amount of deferred fees paid by borrowers and unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of loans that are being amortized into income as an adjustment to yield. Excludes amounts for loans and leases covered under loss sharing agreements.

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