Loans and ALLL (Summary of changes in ALLL by segments) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	$ 9,271	$ 8,697	$ 9,744	$ 7,939
Allowance for loan losses, Charge-offs	(53)	(66)	(212)	(224)
Allowance for loan losses, Recoveries	111	141	320	269
Allowance for loan losses, Provision for loan losses	31	105	(492)	893
Allowance for loan losses, Ending Balance	9,360	8,877	9,360	8,877
Commercial [Member]
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	1,699	2,375	2,162	1,914
Allowance for loan losses, Charge-offs	0	(1)	(31)	(5)
Allowance for loan losses, Recoveries	17	30	99	52
Allowance for loan losses, Provision for loan losses	595	(283)	81	160
Allowance for loan losses, Ending Balance	2,311	2,121	2,311	2,121
Agricultural [Member]
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	230	490	311	634
Allowance for loan losses, Charge-offs	0	(6)	0	(22)
Allowance for loan losses, Recoveries	3	2	5	35
Allowance for loan losses, Provision for loan losses	15	(130)	(68)	(291)
Allowance for loan losses, Ending Balance	248	356	248	356
Residential Real Estate [Member]
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	1,163	1,717	1,363	2,047
Allowance for loan losses, Charge-offs	0	0	0	(15)
Allowance for loan losses, Recoveries	48	39	103	66
Allowance for loan losses, Provision for loan losses	(257)	(563)	(512)	(905)
Allowance for loan losses, Ending Balance	954	1,193	954	1,193
Consumer Portfolio Segment [Member]
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	956	961	798	922
Allowance for loan losses, Charge-offs	(53)	(59)	(181)	(182)
Allowance for loan losses, Recoveries	43	70	113	116
Allowance for loan losses, Provision for loan losses	(8)	(147)	208	(31)
Allowance for loan losses, Ending Balance	938	825	938	825
Unallocated [Member]
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	5,223	3,154	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	(314)	1,228	(201)	1,960
Allowance for loan losses, Ending Balance	$ 4,909	$ 4,382	$ 4,909	$ 4,382

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

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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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