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Loans and ALLL (Summary of changes in ALLL by segments) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans and Leases Receivable, Allowance	$ 7,939	$ 8,375
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	8,375	7,700
Allowance for loan losses, Charge-offs	(948)	(1,101)
Allowance for loan losses, Recoveries	482	798
Allowance for loan losses, Provision for loan losses	30	978	$ 253
Allowance for loan losses, Ending Balance	7,939	8,375	7,700
Commercial [Member]
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	2,563	1,706
Allowance for loan losses, Charge-offs	(143)	(575)
Allowance for loan losses, Recoveries	123	325
Allowance for loan losses, Provision for loan losses	(629)	1,107
Allowance for loan losses, Ending Balance	1,914	2,563	1,706
Agricultural [Member]
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	775	611
Allowance for loan losses, Charge-offs	(240)	(51)
Allowance for loan losses, Recoveries	3	3
Allowance for loan losses, Provision for loan losses	96	212
Allowance for loan losses, Ending Balance	634	775	611
Residential Real Estate [Member]
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	1,992	2,563
Allowance for loan losses, Charge-offs	(99)	(151)
Allowance for loan losses, Recoveries	189	261
Allowance for loan losses, Provision for loan losses	(35)	(681)
Allowance for loan losses, Ending Balance	2,047	1,992	2,563
Consumer [Member]
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	857	900
Allowance for loan losses, Charge-offs	(466)	(324)
Allowance for loan losses, Recoveries	167	209
Allowance for loan losses, Provision for loan losses	364	72
Allowance for loan losses, Ending Balance	922	857	900
Unallocated [Member]
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	2,188	1,920
Allowance for loan losses, Charge-offs	0	0
Allowance for loan losses, Recoveries	0	0
Allowance for loan losses, Provision for loan losses	234	268
Allowance for loan losses, Ending Balance	$ 2,422	$ 2,188	$ 1,920

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A valuation allowance for financing receivables that are expected to be uncollectible.

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Amount of recovery of financing receivables doubtful of collection that were previously charged off.

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Amount of direct write-downs of financing receivables charged against the allowance.

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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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