Loans, Allowance for Loan Losses (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Allowance for loan losses [Roll Forward]
Beginning balance	$ 11,133	$ 10,899	$ 9,251
Provision for loan losses	2,100	600	1,800
Charge-offs	(685)	(835)	(539)
Recoveries	274	469	387
Net charge-offs	(411)	(366)	(152)
Ending balance	12,822	11,133	10,899
Period-end amount allocated to [Abstract]
Loans individually evaluated for impairment	855	470	1,644
Loans collectively evaluated for impairment	11,967	10,663	9,255
Ending balance	12,822	11,133	10,899
Loans individually and collectively evaluated for impairment [Abstract]
Loans individually evaluated for impairment	10,874	9,001	10,959
Loans collectively evaluated for impairment	764,620	740,195	668,604
Ending balance	775,494	749,196	679,563
Commercial [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	2,625	3,571	3,097
Provision for loan losses	1,036	(567)	883
Charge-offs	(509)	(681)	(446)
Recoveries	46	302	37
Net charge-offs	(463)	(379)	(409)
Ending balance	3,198	2,625	3,571
Period-end amount allocated to [Abstract]
Loans individually evaluated for impairment	496	53	898
Loans collectively evaluated for impairment	2,702	2,572	2,673
Ending balance	3,198	2,625	3,571
Loans individually and collectively evaluated for impairment [Abstract]
Loans individually evaluated for impairment	2,902	3,660	5,578
Loans collectively evaluated for impairment	122,275	131,355	120,733
Ending balance	125,177	135,015	126,311
Commercial Real Estate [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	5,460	3,910	3,343
Provision for loan losses	572	1,550	582
Charge-offs	(142)	0	(15)
Recoveries	0	0	0
Net charge-offs	(142)	0	(15)
Ending balance	5,890	5,460	3,910
Period-end amount allocated to [Abstract]
Loans individually evaluated for impairment	21	36	39
Loans collectively evaluated for impairment	5,869	5,424	3,871
Ending balance	5,890	5,460	3,910
Loans individually and collectively evaluated for impairment [Abstract]
Loans individually evaluated for impairment	642	1,996	823
Loans collectively evaluated for impairment	419,464	396,350	343,387
Ending balance	420,106	398,346	344,210
Agriculture [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	1,547	1,262	1,060
Provision for loan losses	85	285	121
Charge-offs	0	0	0
Recoveries	0	0	81
Net charge-offs	0	0	81
Ending balance	1,632	1,547	1,262
Period-end amount allocated to [Abstract]
Loans individually evaluated for impairment	0	0	0
Loans collectively evaluated for impairment	1,632	1,547	1,262
Ending balance	1,632	1,547	1,262
Loans individually and collectively evaluated for impairment [Abstract]
Loans individually evaluated for impairment	4,830	0	0
Loans collectively evaluated for impairment	118,796	113,555	101,905
Ending balance	123,626	113,555	101,905
Residential Mortgage [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	628	660	739
Provision for loan losses	(19)	(7)	(67)
Charge-offs	0	(121)	(13)
Recoveries	34	96	1
Net charge-offs	34	(25)	(12)
Ending balance	643	628	660
Period-end amount allocated to [Abstract]
Loans individually evaluated for impairment	287	302	584
Loans collectively evaluated for impairment	356	326	76
Ending balance	643	628	660
Loans individually and collectively evaluated for impairment [Abstract]
Loans individually evaluated for impairment	1,551	2,277	3,034
Loans collectively evaluated for impairment	49,513	39,804	37,203
Ending balance	51,064	42,081	40,237
Residential Construction [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	360	440	334
Provision for loan losses	(173)	(85)	101
Charge-offs	0	0	0
Recoveries	131	5	5
Net charge-offs	131	5	5
Ending balance	318	360	440
Period-end amount allocated to [Abstract]
Loans individually evaluated for impairment	49	76	98
Loans collectively evaluated for impairment	269	284	342
Ending balance	318	360	440
Loans individually and collectively evaluated for impairment [Abstract]
Loans individually evaluated for impairment	560	650	820
Loans collectively evaluated for impairment	19,564	20,649	22,830
Ending balance	20,124	21,299	23,650
Consumer [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	342	498	641
Provision for loan losses	(92)	(189)	(341)
Charge-offs	(34)	(33)	(65)
Recoveries	63	66	263
Net charge-offs	29	33	198
Ending balance	279	342	498
Period-end amount allocated to [Abstract]
Loans individually evaluated for impairment	2	3	25
Loans collectively evaluated for impairment	277	339	473
Ending balance	279	342	498
Loans individually and collectively evaluated for impairment [Abstract]
Loans individually evaluated for impairment	389	418	704
Loans collectively evaluated for impairment	35,008	38,482	42,546
Ending balance	35,397	38,900	43,250
Unallocated [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	171	558	37
Provision for loan losses	691	(387)	521
Charge-offs	0	0	0
Recoveries	0	0	0
Net charge-offs	0	0	0
Ending balance	862	171	558
Period-end amount allocated to [Abstract]
Loans individually evaluated for impairment	0	0	0
Loans collectively evaluated for impairment	862	171	558
Ending balance	$ 862	$ 171	$ 558