Loans and ALLL (Summary of changes in ALLL by segments) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans and Leases Receivable, Allowance	$ 8,375	$ 7,700
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	7,700	7,400
Allowance for loan losses, Charge-offs	(1,101)	(771)
Allowance for loan losses, Recoveries	798	818
Allowance for loan losses, Provision for loan losses	978	253	$ (135)
Allowance for loan losses, Ending Balance	8,375	7,700	7,400
Commercial [Member]
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	1,706	1,814
Allowance for loan losses, Charge-offs	(626)	(265)
Allowance for loan losses, Recoveries	328	453
Allowance for loan losses, Provision for loan losses	1,155	(296)
Allowance for loan losses, Ending Balance	2,563	1,706	1,814
Agricultural [Member]
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	611	884
Allowance for loan losses, Charge-offs	0	0
Allowance for loan losses, Recoveries	0	0
Allowance for loan losses, Provision for loan losses	164	(273)
Allowance for loan losses, Ending Balance	775	611	884
Residential Real Estate [Member]
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	2,563	2,664
Allowance for loan losses, Charge-offs	(151)	(200)
Allowance for loan losses, Recoveries	261	206
Allowance for loan losses, Provision for loan losses	(681)	(107)
Allowance for loan losses, Ending Balance	1,992	2,563	2,664
Consumer [Member]
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	900	624
Allowance for loan losses, Charge-offs	(324)	(306)
Allowance for loan losses, Recoveries	209	159
Allowance for loan losses, Provision for loan losses	72	423
Allowance for loan losses, Ending Balance	857	900	624
Unallocated [Member]
Summary of changes in the ALLL and the recorded investment in loans by segments
Allowance for loan losses, Beginning Balance	1,920	1,414
Allowance for loan losses, Charge-offs	0	0
Allowance for loan losses, Recoveries	0	0
Allowance for loan losses, Provision for loan losses	268	506
Allowance for loan losses, Ending Balance	$ 2,188	$ 1,920	$ 1,414

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

A valuation allowance for financing receivables that are expected to be uncollectible.

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

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Amount of direct write-downs of financing receivables charged against the allowance.

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- Definition

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.

+ References

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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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