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Loans and ALLL (Summary of changes in ALLL by segments) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
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	(159)	(158)
Allowance for loan losses, Recoveries	209	128
Allowance for loan losses, Provision for loan losses	(523)	788
Allowance for loan losses, Ending Balance	9,271	8,697
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	(31)	(4)
Allowance for loan losses, Recoveries	82	22
Allowance for loan losses, Provision for loan losses	(514)	443
Allowance for loan losses, Ending Balance	1,699	2,375
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	0	(16)
Allowance for loan losses, Recoveries	2	33
Allowance for loan losses, Provision for loan losses	(83)	(161)
Allowance for loan losses, Ending Balance	230	490
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	0	(15)
Allowance for loan losses, Recoveries	55	27
Allowance for loan losses, Provision for loan losses	(255)	(342)
Allowance for loan losses, Ending Balance	1,163	1,717
Consumer Portfolio Segment [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	(128)	(123)
Allowance for loan losses, Recoveries	70	46
Allowance for loan losses, Provision for loan losses	216	116
Allowance for loan losses, Ending Balance	956	961
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	113	732
Allowance for loan losses, Ending Balance	$ 5,223	$ 3,154

X

- Definition

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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- Definition

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

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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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