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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, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Commercial & industrial [Member]
Summary of Impaired loan activity
With no related allowance recorded, Recorded Investment	$ 624		$ 624		$ 575
With no related allowance recorded, Unpaid Principal Balance	899	$ 32	899	$ 32	802
With no related allowance recorded, Related Allowance
With no related allowance recorded, Average Recorded Investment	1,226		1,275		370
With no related allowance recorded, Interest Income Recognized	19		44		21
With a specific allowance recorded, Recorded Investment					125
With a specific allowance recorded, Unpaid Principal Balance					125
With a specific allowance recorded, Related Allowance					61
With a specific allowance recorded, Average Recorded Investment					127
With a specific allowance recorded, Interest Income Recognized					21
Total Recorded Investment	624		624		700
Total Unpaid Principal Balance	899	32	899	32	927
Total Related Allowance					61
Total Average Recorded Investment	1,226		1,275		497
Total Interest Income Recognized	19		44		42
Commercial real estate - owner occupied [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 real estate - nonowner occupied [Member]
Summary of Impaired loan activity
With no related allowance recorded, Recorded Investment	208		208		283
With no related allowance recorded, Unpaid Principal Balance	208	506	208	506	283
With no related allowance recorded, Related Allowance
With no related allowance recorded, Average Recorded Investment	259	337	259	337	336
With no related allowance recorded, Interest Income Recognized	3	6	10	12	21
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	208		208		283
Total Unpaid Principal Balance	208	506	208	506	283
Total Related Allowance
Total Average Recorded Investment	259	337	259	337	336
Total Interest Income Recognized	3	6	10	12	21
Agricultural [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	1,746		1,746		1,249
With no related allowance recorded, Unpaid Principal Balance	1,789	1,485	1,789	1,485	1,292
With no related allowance recorded, Related Allowance
With no related allowance recorded, Average Recorded Investment	2,055	1,996	2,065	2,000	1,995
With no related allowance recorded, Interest Income Recognized	27	21	56	41	91
With a specific allowance recorded, Recorded Investment	526		526		862
With a specific allowance recorded, Unpaid Principal Balance	526	1,160	526	1,160	888
With a specific allowance recorded, Related Allowance	47		47		73
With a specific allowance recorded, Average Recorded Investment	531	569	534	572	426
With a specific allowance recorded, Interest Income Recognized	7	7	12	14	20
Total Recorded Investment	2,272		2,272		2,111
Total Unpaid Principal Balance	2,351	2,645	2,351	2,645	21,180
Total Related Allowance	47		47		73
Total Average Recorded Investment	2,586	2,565	2,599	2,572	2,421
Total Interest Income Recognized	34	28	68	55	111
HELOC [Member]
Summary of Impaired loan activity
With no related allowance recorded, Recorded Investment	17		17		20
With no related allowance recorded, Unpaid Principal Balance	17		17		20
With no related allowance recorded, Related Allowance
With no related allowance recorded, Average Recorded Investment	19		19		21
With no related allowance recorded, Interest Income Recognized			1		1
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	17		17		20
Total Unpaid Principal Balance	17		17		20
Total Related Allowance
Total Average Recorded Investment	19		19		21
Total Interest Income Recognized			1		1
Consumer [Member]
Summary of Impaired loan activity
With no related allowance recorded, Recorded Investment	19		19		93
With no related allowance recorded, Unpaid Principal Balance	19		19		93
With no related allowance recorded, Related Allowance
With no related allowance recorded, Average Recorded Investment	20	114	20	116	104
With no related allowance recorded, Interest Income Recognized		2	1	4	7
With a specific allowance recorded, Recorded Investment					77
With a specific allowance recorded, Unpaid Principal Balance		10		10	77
With a specific allowance recorded, Related Allowance					4
With a specific allowance recorded, Average Recorded Investment		84		85	91
With a specific allowance recorded, Interest Income Recognized		1		3	6
Total Recorded Investment	19		19		170
Total Unpaid Principal Balance	19	10	19	10	170
Total Related Allowance					4
Total Average Recorded Investment	20	198	20	201	195
Total Interest Income Recognized		$ 3	$ 1	$ 7	$ 13