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Loans and ALLL (Summary of recorded investment in loans by segments) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017
Financing Receivable, Allowance for Credit Losses [Line Items]
Individually evaluated for impairment, ALLL	$ 1,479		$ 1,938
Collectively evaluated for impairment, ALLL	6,558		6,437
Total, ALLL	8,037	$ 8,398	8,375	$ 8,200	$ 8,200	$ 7,700
Individually evaluated for impairment, Loans	28,897		31,099
Collectively evaluated for impairment, Loans	1,147,725		1,097,608
Total	1,176,622		1,128,707
Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Individually evaluated for impairment, ALLL	58		443
Collectively evaluated for impairment, ALLL	2,022		2,120
Total, ALLL	2,080	2,248	2,563	2,197	1,840	1,706
Individually evaluated for impairment, Loans	9,029		9,899
Collectively evaluated for impairment, Loans	692,925		649,630
Total	701,954		659,529
Agricultural [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Individually evaluated for impairment, ALLL	123		132
Collectively evaluated for impairment, ALLL	489		643
Total, ALLL	612	775	775	982	1,224	611
Individually evaluated for impairment, Loans	13,472		14,298
Collectively evaluated for impairment, Loans	106,891		112,863
Total	120,363		127,161
Residential Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Individually evaluated for impairment, ALLL	1,298		1,363
Collectively evaluated for impairment, ALLL	584		629
Total, ALLL	1,882	2,305	1,992	2,167	2,482	2,563
Individually evaluated for impairment, Loans	6,389		6,893
Collectively evaluated for impairment, Loans	276,896		268,450
Total	283,285		275,343
Total Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Individually evaluated for impairment, ALLL	0		0
Collectively evaluated for impairment, ALLL	927		857
Total, ALLL	927	891	857	882	795	900
Individually evaluated for impairment, Loans	7		9
Collectively evaluated for impairment, Loans	71,013		66,665
Total	71,020		66,674
Unallocated [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Individually evaluated for impairment, ALLL	0		0
Collectively evaluated for impairment, ALLL	2,536		2,188
Total, ALLL	$ 2,536	$ 2,179	$ 2,188	$ 1,972	$ 1,859	$ 1,920

X

- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
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