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Loans and Allowance for Loan Losses (Details 4) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Commercial & Industrial [Member]
Summary of Impaired loan activity
With no related allowance recorded, Recorded Investment
With no related allowance recorded, Unpaid Principal Balance
With no related allowance recorded, Related Allowance
With no related allowance recorded, Average Recorded Investment
With no related allowance recorded, Interest Income Recognized
With a specific allowance recorded, Recorded Investment
With a specific allowance recorded, Unpaid Principal Balance
With a specific allowance recorded, Related Allowance
With a specific allowance recorded, Average Recorded Investment
With a specific allowance recorded, Interest Income Recognized
Total Recorded Investment
Total Unpaid Principal Balance
Total Related Allowance
Total Average Recorded Investment
Total Interest Income Recognized
Commercial RE & Construction [Member]
Summary of Impaired loan activity
With no related allowance recorded, Recorded Investment	294		294		696
With no related allowance recorded, Unpaid Principal Balance	294	735	294	735	722
With no related allowance recorded, Related Allowance
With no related allowance recorded, Average Recorded Investment	337	758	337	735	756
With no related allowance recorded, Interest Income Recognized	6	22	12		34
With a specific allowance recorded, Recorded Investment					689
With a specific allowance recorded, Unpaid Principal Balance		689		689	689
With a specific allowance recorded, Related Allowance					146
With a specific allowance recorded, Average Recorded Investment		738		689	713
With a specific allowance recorded, Interest Income Recognized		(2)
Total Recorded Investment	294		294		1,385
Total Unpaid Principal Balance	294	1,424	294	1,424	1,411
Total Related Allowance					146
Total Average Recorded Investment	337	1,496	337	1,424	1,469
Total Interest Income Recognized	6	20	12		34
Agricultural & Farmland [Member]
Summary of Impaired loan activity
With no related allowance recorded, Recorded Investment
With no related allowance recorded, Unpaid Principal Balance
With no related allowance recorded, Related Allowance
With no related allowance recorded, Average Recorded Investment
With no related allowance recorded, Interest Income Recognized
With a specific allowance recorded, Recorded Investment
With a specific allowance recorded, Unpaid Principal Balance
With a specific allowance recorded, Related Allowance
With a specific allowance recorded, Average Recorded Investment
With a specific allowance recorded, Interest Income Recognized
Total Recorded Investment
Total Unpaid Principal Balance
Total Related Allowance
Total Average Recorded Investment
Total Interest Income Recognized
Residential Real Estate [Member]
Summary of Impaired loan activity
With no related allowance recorded, Recorded Investment	1,275		1,275		752
With no related allowance recorded, Unpaid Principal Balance	1,319	1,157	1,319	1,157	795
With no related allowance recorded, Related Allowance
With no related allowance recorded, Average Recorded Investment	1,996	1,351	2,000	1,114	1,460
With no related allowance recorded, Interest Income Recognized	21	35	41		67
With a specific allowance recorded, Recorded Investment	1,016		1,016		1,078
With a specific allowance recorded, Unpaid Principal Balance	1,041	561	1,041	561	1,097
With a specific allowance recorded, Related Allowance	136		136		178
With a specific allowance recorded, Average Recorded Investment	569	634	572	561	628
With a specific allowance recorded, Interest Income Recognized	7	13	14		25
Total Recorded Investment	2,291		2,291		1,830
Total Unpaid Principal Balance	2,360	1,718	2,360	1,718	1,892
Total Related Allowance	136		136		178
Total Average Recorded Investment	2,565	1,985	2,572	1,675	2,088
Total Interest Income Recognized	28	48	55		92
Consumer & Other [Member]
Summary of Impaired loan activity
With no related allowance recorded, Recorded Investment	100		100		110
With no related allowance recorded, Unpaid Principal Balance	100	118	100	118	110
With no related allowance recorded, Related Allowance
With no related allowance recorded, Average Recorded Investment	114	145	116	118	128
With no related allowance recorded, Interest Income Recognized	2	5	4		9
With a specific allowance recorded, Recorded Investment	83		83		87
With a specific allowance recorded, Unpaid Principal Balance	83	112	83	112	87
With a specific allowance recorded, Related Allowance	4		4		5
With a specific allowance recorded, Average Recorded Investment	84	118	85	112	91
With a specific allowance recorded, Interest Income Recognized	1	3	3		5
Total Recorded Investment	183		183		197
Total Unpaid Principal Balance	183	230	183	230	197
Total Related Allowance	4		4		5
Total Average Recorded Investment	198	263	201	$ 230	219
Total Interest Income Recognized	$ 3	$ 8	$ 7		$ 14