Loans (Details) $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($) Category	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Loan Portfolio by Loan Class [Abstract]
Loans	$ 780,645	$ 775,494	$ 749,196
Allowance for loan losses	(12,356)	(12,822)	(11,133)	$ (10,899)
Net deferred origination fees and costs	584	721
Loans, net	$ 768,873	763,393
Minimum [Member]
Loan Portfolio by Loan Class [Abstract]
Delinquent loans revaluation period	3 months
Maximum [Member]
Loan Portfolio by Loan Class [Abstract]
Delinquent loans revaluation period	12 months
Commercial [Member]
Loan Portfolio by Loan Class [Abstract]
Loans	$ 106,140	125,177	135,015
Allowance for loan losses	$ (2,354)	(3,198)	(2,625)	(3,571)
Loan portfolio by segment	14.00%
Commercial Real Estate [Member]
Loan Portfolio by Loan Class [Abstract]
Loans	$ 451,774	420,106	398,346
Allowance for loan losses	$ (6,846)	(5,890)	(5,460)	(3,910)
Categories of loans \| Category	2
Loan portfolio by segment	58.00%
Agriculture [Member]
Loan Portfolio by Loan Class [Abstract]
Loans	$ 115,751	123,626	113,555
Allowance for loan losses	$ (2,054)	(1,632)	(1,547)	(1,262)
Loan portfolio by segment	15.00%
Residential Mortgage [Member]
Loan Portfolio by Loan Class [Abstract]
Loans	$ 64,943	51,064	42,081
Allowance for loan losses	$ (466)	(643)	(628)	(660)
Loan portfolio by segment	8.00%
Residential Construction [Member]
Loan Portfolio by Loan Class [Abstract]
Loans	$ 15,212	20,124	21,299
Allowance for loan losses	$ (201)	(318)	(360)	(440)
Loan portfolio by segment	2.00%
Consumer [Member]
Loan Portfolio by Loan Class [Abstract]
Loans	$ 26,825	35,397	38,900
Allowance for loan losses	$ (236)	$ (279)	$ (342)	$ (498)
Loan portfolio by segment	3.00%

Categories of commercial real estate loans.

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The time frame when revaluation can occur on delinquent loans depending on the underlying collateral and volatility of values, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The percentage of the loan portfolio by segment.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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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 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 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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