Loans and ALLL (Summary of recorded investment in loans by segments) (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Financing Receivable, Allowance for Credit Losses [Line Items]
Individually evaluated for impairment, ALLL	$ 1,309	$ 1,114
Collectively evaluated for impairment, ALLL	7,388	6,825
Total, ALLL	8,697	7,939	$ 8,398	$ 8,375
Individually evaluated for impairment, Loans	27,635	28,191
Collectively evaluated for impairment, Loans	1,148,301	1,158,379
Total	1,175,936	1,186,570
Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Individually evaluated for impairment, ALLL	179	15
Collectively evaluated for impairment, ALLL	2,196	1,899
Total, ALLL	2,375	1,914	2,248	2,563
Individually evaluated for impairment, Loans	8,598	7,865
Collectively evaluated for impairment, Loans	686,680	693,076
Total	695,278	700,941
Agricultural [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Individually evaluated for impairment, ALLL	78	26
Collectively evaluated for impairment, ALLL	412	608
Total, ALLL	490	634	775	775
Individually evaluated for impairment, Loans	13,660	14,840
Collectively evaluated for impairment, Loans	95,196	102,080
Total	108,856	116,920
Residential Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Individually evaluated for impairment, ALLL	1,052	1,073
Collectively evaluated for impairment, ALLL	665	974
Total, ALLL	1,717	2,047	2,305	1,992
Individually evaluated for impairment, Loans	5,374	5,486
Collectively evaluated for impairment, Loans	296,642	293,083
Total	302,016	298,569
Total Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Individually evaluated for impairment, ALLL	0	0
Collectively evaluated for impairment, ALLL	961	922
Total, ALLL	961	922	891	857
Individually evaluated for impairment, Loans	3	0
Collectively evaluated for impairment, Loans	69,783	70,140
Total	69,786	70,140
Unallocated [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Individually evaluated for impairment, ALLL	0	0
Collectively evaluated for impairment, ALLL	3,154	2,422
Total, ALLL	$ 3,154	$ 2,422	$ 2,179	$ 2,188

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

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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