Loans, Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Recorded Investment
With no related allowance recorded	$ 22,316		$ 26,840
With an allowance recorded	1,129		1,102
Total	23,445		27,942
Unpaid Principal Balance
With no related allowance recorded	24,673		29,445
With an allowance recorded	1,346		1,126
Total	26,019		30,571
Related Allowance
With an allowance recorded	47		62
Average Recorded Investment
With no related allowance recorded	23,338	$ 19,011
With an allowance recorded	1,147	1,244
Total	24,485	20,255
Interest Income Recognized
With no related allowance recorded	262	263
With an allowance recorded	24	17
Total	286	280
Cash basis interest expense on impaired loans	0	20
Commercial and industrial [Member]
Recorded Investment
With no related allowance recorded	608		926
With an allowance recorded	255		264
Total	863		1,190
Unpaid Principal Balance
With no related allowance recorded	1,143		1,457
With an allowance recorded	261		269
Total	1,404		1,726
Related Allowance
With an allowance recorded	9		10
Average Recorded Investment
With no related allowance recorded	767	639
With an allowance recorded	259	291
Total	1,026	930
Interest Income Recognized
With no related allowance recorded	7	11
With an allowance recorded	4	4
Total	11	15
Commercial, secured by real estate [Member]
Recorded Investment
With no related allowance recorded	17,465		21,266
With an allowance recorded	241		150
Total	17,706		21,416
Unpaid Principal Balance
With no related allowance recorded	18,459		22,451
With an allowance recorded	427		150
Total	18,886		22,601
Related Allowance
With an allowance recorded	9		3
Average Recorded Investment
With no related allowance recorded	18,302	14,991
With an allowance recorded	244	157
Total	18,546	15,148
Interest Income Recognized
With no related allowance recorded	199	196
With an allowance recorded	12	3
Total	211	199
Residential real estate [Member]
Recorded Investment
With no related allowance recorded	3,886		4,122
With an allowance recorded	612		665
Total	4,498		4,787
Unpaid Principal Balance
With no related allowance recorded	4,583		4,872
With an allowance recorded	637		684
Total	5,220		5,556
Related Allowance
With an allowance recorded	29		49
Average Recorded Investment
With no related allowance recorded	3,916	2,791
With an allowance recorded	622	755
Total	4,538	3,546
Interest Income Recognized
With no related allowance recorded	47	45
With an allowance recorded	8	9
Total	55	54
Consumer [Member]
Recorded Investment
With no related allowance recorded	13		13
With an allowance recorded	21		23
Total	34		36
Unpaid Principal Balance
With no related allowance recorded	13		13
With an allowance recorded	21		23
Total	34		36
Related Allowance
With an allowance recorded	0		0
Average Recorded Investment
With no related allowance recorded	13	6
With an allowance recorded	22	41
Total	35	47
Interest Income Recognized
With no related allowance recorded	0	0
With an allowance recorded	0	1
Total	0	1
Agricultural [Member]
Recorded Investment
With no related allowance recorded	0		177
With an allowance recorded	0		0
Total	0		177
Unpaid Principal Balance
With no related allowance recorded	0		177
With an allowance recorded	0		0
Total	0		177
Related Allowance
With an allowance recorded	0		0
Average Recorded Investment
With no related allowance recorded	0	177
With an allowance recorded	0	0
Total	0	177
Interest Income Recognized
With no related allowance recorded	0	0
With an allowance recorded	0	0
Total	0	0
Other [Member]
Recorded Investment
With no related allowance recorded	344		336
With an allowance recorded	0		0
Total	344		336
Unpaid Principal Balance
With no related allowance recorded	475		475
With an allowance recorded	0		0
Total	475		475
Related Allowance
With an allowance recorded	0		$ 0
Average Recorded Investment
With no related allowance recorded	340	407
With an allowance recorded	0	0
Total	340	407
Interest Income Recognized
With no related allowance recorded	9	11
With an allowance recorded	0	0
Total	$ 9	$ 11