Loans (Details) $ in Thousands	12 Months Ended
Dec. 31, 2018 USD ($) Category	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Loan Portfolio by Loan Class [Abstract]
Loans	$ 775,494	$ 749,196	$ 679,563
Allowance for loan losses	(12,822)	(11,133)	(10,899)	$ (9,251)
Net deferred origination fees and costs	721	1,049
Loans, net	$ 763,393	739,112
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	$ 125,177	135,015	126,311
Allowance for loan losses	$ (3,198)	(2,625)	(3,571)	(3,097)
Loan portfolio by segment	16.00%
Commercial Real Estate [Member]
Loan Portfolio by Loan Class [Abstract]
Loans	$ 420,106	398,346	344,210
Allowance for loan losses	$ (5,890)	(5,460)	(3,910)	(3,343)
Categories of loans \| Category	2
Loan portfolio by segment	54.00%
Agriculture [Member]
Loan Portfolio by Loan Class [Abstract]
Loans	$ 123,626	113,555	101,905
Allowance for loan losses	$ (1,632)	(1,547)	(1,262)	(1,060)
Loan portfolio by segment	16.00%
Residential Mortgage [Member]
Loan Portfolio by Loan Class [Abstract]
Loans	$ 51,064	42,081	40,237
Allowance for loan losses	$ (643)	(628)	(660)	(739)
Loan portfolio by segment	7.00%
Residential Construction [Member]
Loan Portfolio by Loan Class [Abstract]
Loans	$ 20,124	21,299	23,650
Allowance for loan losses	$ (318)	(360)	(440)	(334)
Loan portfolio by segment	3.00%
Consumer [Member]
Loan Portfolio by Loan Class [Abstract]
Loans	$ 35,397	38,900	43,250
Allowance for loan losses	$ (279)	$ (342)	$ (498)	$ (641)
Loan portfolio by segment	4.00%

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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