Loans and ALLL (Summary of changes in ALLL by segments) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans and Leases Receivable, Allowance	$ 9,744	$ 7,939
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	7,939	8,375
Allowance for loan losses, Charge-offs	(381)	(948)
Allowance for loan losses, Recoveries	521	482
Allowance for loan losses, Provision for loan losses	1,665	30	$ 978
Allowance for loan losses, Ending Balance	9,744	7,939	8,375
Commercial [Member]
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	1,914	2,563
Allowance for loan losses, Charge-offs	(7)	(143)
Allowance for loan losses, Recoveries	149	123
Allowance for loan losses, Provision for loan losses	106	(629)
Allowance for loan losses, Ending Balance	2,162	1,914	2,563
Agricultural [Member]
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	634	775
Allowance for loan losses, Charge-offs	(24)	(240)
Allowance for loan losses, Recoveries	39	3
Allowance for loan losses, Provision for loan losses	(338)	96
Allowance for loan losses, Ending Balance	311	634	775
Residential Real Estate [Member]
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	2,047	1,992
Allowance for loan losses, Charge-offs	(28)	(99)
Allowance for loan losses, Recoveries	136	189
Allowance for loan losses, Provision for loan losses	(792)	(35)
Allowance for loan losses, Ending Balance	1,363	2,047	1,992
Consumer [Member]
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	922	857
Allowance for loan losses, Charge-offs	(322)	(466)
Allowance for loan losses, Recoveries	197	167
Allowance for loan losses, Provision for loan losses	1	364
Allowance for loan losses, Ending Balance	798	922	857
Unallocated [Member]
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	2,422	2,188
Allowance for loan losses, Charge-offs	0	0
Allowance for loan losses, Recoveries	0	0
Allowance for loan losses, Provision for loan losses	2,688	234
Allowance for loan losses, Ending Balance	$ 5,110	$ 2,422	$ 2,188

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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