Loans and ALLL (Summary of changes in ALLL by segments) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans and Leases Receivable, Allowance	$ 9,103	$ 9,744
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	9,744	7,939
Allowance for loan losses, Charge-offs	(607)	(381)
Allowance for loan losses, Recoveries	484	521
Allowance for loan losses, Provision for loan losses	(518)	1,665	$ 30
Allowance for loan losses, Ending Balance	9,103	9,744	7,939
Commercial [Member]
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	2,162	1,914
Allowance for loan losses, Charge-offs	(32)	(7)
Allowance for loan losses, Recoveries	133	149
Allowance for loan losses, Provision for loan losses	(523)	106
Allowance for loan losses, Ending Balance	1,740	2,162	1,914
Agricultural [Member]
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	311	634
Allowance for loan losses, Charge-offs	(77)	(24)
Allowance for loan losses, Recoveries	12	39
Allowance for loan losses, Provision for loan losses	43	(338)
Allowance for loan losses, Ending Balance	289	311	634
Residential Real Estate [Member]
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	1,363	2,047
Allowance for loan losses, Charge-offs	(12)	(28)
Allowance for loan losses, Recoveries	162	136
Allowance for loan losses, Provision for loan losses	(766)	(792)
Allowance for loan losses, Ending Balance	747	1,363	2,047
Consumer [Member]
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	798	922
Allowance for loan losses, Charge-offs	(486)	(322)
Allowance for loan losses, Recoveries	177	197
Allowance for loan losses, Provision for loan losses	419	1
Allowance for loan losses, Ending Balance	908	798	922
Unallocated [Member]
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	5,110	2,422
Allowance for loan losses, Charge-offs	0	0
Allowance for loan losses, Recoveries	0	0
Allowance for loan losses, Provision for loan losses	309	2,688
Allowance for loan losses, Ending Balance	$ 5,419	$ 5,110	$ 2,422

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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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Amount of increase in allowance for credit loss on financing receivable from recovery.

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Amount of writeoff of financing receivable, charged against allowance for credit loss.

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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 of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

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