Loans and ALLL (Summary of changes in ALLL by segments) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	$ 9,360	$ 8,877	$ 9,744	$ 7,939
Allowance for loan losses, Charge-offs	(246)	(46)	(458)	(270)
Allowance for loan losses, Recoveries	86	159	406	428
Allowance for loan losses, Provision for loan losses	(107)	516	(599)	1,409
Allowance for loan losses, Ending Balance	9,093	9,506	9,093	9,506
Commercial [Member]
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	2,311	2,121	2,162	1,914
Allowance for loan losses, Charge-offs	(1)	(2)	(32)	(7)
Allowance for loan losses, Recoveries	22	81	121	133
Allowance for loan losses, Provision for loan losses	(801)	(255)	(720)	(95)
Allowance for loan losses, Ending Balance	1,531	1,945	1,531	1,945
Agricultural [Member]
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	248	356	311	634
Allowance for loan losses, Charge-offs	(77)	0	(77)	(22)
Allowance for loan losses, Recoveries	1	2	6	37
Allowance for loan losses, Provision for loan losses	294	(16)	226	(307)
Allowance for loan losses, Ending Balance	466	342	466	342
Residential Real Estate [Member]
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	954	1,193	1,363	2,047
Allowance for loan losses, Charge-offs	0	(13)	0	(28)
Allowance for loan losses, Recoveries	29	36	132	102
Allowance for loan losses, Provision for loan losses	(226)	90	(738)	(815)
Allowance for loan losses, Ending Balance	757	1,306	757	1,306
Consumer Portfolio Segment [Member]
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	938	825	798	922
Allowance for loan losses, Charge-offs	(168)	(31)	(349)	(213)
Allowance for loan losses, Recoveries	34	40	147	156
Allowance for loan losses, Provision for loan losses	45	21	253	(10)
Allowance for loan losses, Ending Balance	849	855	849	855
Unallocated [Member]
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	4,909	4,382	5,110	2,422
Allowance for loan losses, Charge-offs	0	0	0	0
Allowance for loan losses, Recoveries	0	0	0	0
Allowance for loan losses, Provision for loan losses	581	676	380	2,636
Allowance for loan losses, Ending Balance	$ 5,490	$ 5,058	$ 5,490	$ 5,058

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

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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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