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Loans and Allowance for Loan Losses (Details 4) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Commercial & industrial [Member]
Summary of Impaired loan activity
With no related allowance recorded, Recorded Investment	$ 784		$ 784		$ 575
With no related allowance recorded, Unpaid Principal Balance	1,154		1,154		802
With no related allowance recorded, Related Allowance
With no related allowance recorded, Average Recorded Investment	1,202	$ 763	1,432	$ 777	370
With no related allowance recorded, Interest Income Recognized	22	(9)	46	19	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	784		784		700
Total Unpaid Principal Balance	1,154		1,154		927
Total Related Allowance					61
Total Average Recorded Investment		763	1,432	777	497
Total Interest Income Recognized	19	(9)	76	19	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	203		203		283
With no related allowance recorded, Unpaid Principal Balance	203		203		283
With no related allowance recorded, Related Allowance
With no related allowance recorded, Average Recorded Investment	259	336	259	336	336
With no related allowance recorded, Interest Income Recognized	5	5	15	17	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	203		203		283
Total Unpaid Principal Balance	203		203		283
Total Related Allowance
Total Average Recorded Investment	259	336	259	336	336
Total Interest Income Recognized	5	5	15	17	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	1,481		1,481		1,249
With no related allowance recorded, Unpaid Principal Balance	1,524		1,524		1,292
With no related allowance recorded, Related Allowance
With no related allowance recorded, Average Recorded Investment	1,793	1,733	1,808	1,745	1,995
With no related allowance recorded, Interest Income Recognized	24	16	74	57	91
With a specific allowance recorded, Recorded Investment	526		526		862
With a specific allowance recorded, Unpaid Principal Balance	526		526		888
With a specific allowance recorded, Related Allowance	45		45		73
With a specific allowance recorded, Average Recorded Investment	533	424	538	428	426
With a specific allowance recorded, Interest Income Recognized	6		19	15	20
Total Recorded Investment	2,007		2,007		2,111
Total Unpaid Principal Balance	2,050		2,050		2,180
Total Related Allowance	45		45		73
Total Average Recorded Investment	2,326	2,157	2,346	2,173	2,421
Total Interest Income Recognized	30	21	93	72	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	17		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	17		19		21
Total Interest Income Recognized			1		1
Consumer [Member]
Summary of Impaired loan activity
With no related allowance recorded, Recorded Investment	17		17		93
With no related allowance recorded, Unpaid Principal Balance	17		17		93
With no related allowance recorded, Related Allowance
With no related allowance recorded, Average Recorded Investment	18	102	20	106	104
With no related allowance recorded, Interest Income Recognized		2	1	5	7
With a specific allowance recorded, Recorded Investment					77
With a specific allowance recorded, Unpaid Principal Balance					77
With a specific allowance recorded, Related Allowance					4
With a specific allowance recorded, Average Recorded Investment		90		92	91
With a specific allowance recorded, Interest Income Recognized		1		4	6
Total Recorded Investment	17		17		170
Total Unpaid Principal Balance	17		17		170
Total Related Allowance					4
Total Average Recorded Investment	18	192	20	198	195
Total Interest Income Recognized		$ 3	$ 1	$ 9	$ 13