Loans and ALLL (Summary of changes in ALLL by segments) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	$ 8,877	$ 8,037	$ 7,939	$ 8,375
Allowance for loan losses, Charge-offs	(46)	(143)	(270)	(614)
Allowance for loan losses, Recoveries	159	82	428	360
Allowance for loan losses, Provision for loan losses	516	193	1,409	48
Allowance for loan losses, Ending Balance	9,506	8,169	9,506	8,169
Commercial [Member]
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	2,121	2,080	1,914	2,563
Allowance for loan losses, Charge-offs	(2)	(21)	(7)	(134)
Allowance for loan losses, Recoveries	81	25	133	98
Allowance for loan losses, Provision for loan losses	(255)	(24)	(95)	(467)
Allowance for loan losses, Ending Balance	1,945	2,060	1,945	2,060
Agricultural [Member]
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	356	612	634	775
Allowance for loan losses, Charge-offs	0	(1)	(22)	(60)
Allowance for loan losses, Recoveries	2	1	37	2
Allowance for loan losses, Provision for loan losses	(16)	(57)	(307)	(162)
Allowance for loan losses, Ending Balance	342	555	342	555
Residential Real Estate [Member]
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	1,193	1,882	2,047	1,992
Allowance for loan losses, Charge-offs	(13)	0	(28)	(96)
Allowance for loan losses, Recoveries	36	25	102	143
Allowance for loan losses, Provision for loan losses	90	(38)	(815)	(170)
Allowance for loan losses, Ending Balance	1,306	1,869	1,306	1,869
Consumer Portfolio Segment [Member]
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	825	927	922	857
Allowance for loan losses, Charge-offs	(31)	(121)	(213)	(324)
Allowance for loan losses, Recoveries	40	31	156	117
Allowance for loan losses, Provision for loan losses	21	183	(10)	370
Allowance for loan losses, Ending Balance	855	1,020	855	1,020
Unallocated [Member]
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	4,382	2,536	2,422	2,188
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	676	129	2,636	477
Allowance for loan losses, Ending Balance	$ 5,058	$ 2,665	$ 5,058	$ 2,665

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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- Definition

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

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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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