Loans, Allowance for Loan Losses (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Allowance for loan losses [Roll Forward]
Beginning balance	$ 12,356	$ 12,822	$ 11,133
Provision for loan losses	3,050	0	2,100
Charge-offs	(227)	(779)	(685)
Recoveries	237	313	274
Net charge-offs	10	(466)	(411)
Ending balance	15,416	12,356	12,822
Period-end amount allocated to [Abstract]
Loans individually evaluated for impairment	2,347	273	855
Loans collectively evaluated for impairment	13,069	12,083	11,967
Ending balance	15,416	12,356	12,822
Loans individually and collectively evaluated for impairment [Abstract]
Loans individually evaluated for impairment	17,471	4,475	10,874
Loans collectively evaluated for impairment	875,743	776,170	764,620
Ending balance	893,214	780,645	775,494
Commercial [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	2,354	3,198	2,625
Provision for loan losses	(91)	(415)	1,036
Charge-offs	(212)	(638)	(509)
Recoveries	201	209	46
Net charge-offs	(11)	(429)	(463)
Ending balance	2,252	2,354	3,198
Period-end amount allocated to [Abstract]
Loans individually evaluated for impairment	11	26	496
Loans collectively evaluated for impairment	2,241	2,328	2,702
Ending balance	2,252	2,354	3,198
Loans individually and collectively evaluated for impairment [Abstract]
Loans individually evaluated for impairment	1,024	1,651	2,902
Loans collectively evaluated for impairment	254,902	104,489	122,275
Ending balance	255,926	106,140	125,177
Commercial Real Estate [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	6,846	5,890	5,460
Provision for loan losses	1,069	956	572
Charge-offs	0	0	(142)
Recoveries	0	0	0
Net charge-offs	0	0	(142)
Ending balance	7,915	6,846	5,890
Period-end amount allocated to [Abstract]
Loans individually evaluated for impairment	0	19	21
Loans collectively evaluated for impairment	7,915	6,827	5,869
Ending balance	7,915	6,846	5,890
Loans individually and collectively evaluated for impairment [Abstract]
Loans individually evaluated for impairment	4,875	716	642
Loans collectively evaluated for impairment	449,178	451,058	419,464
Ending balance	454,053	451,774	420,106
Agriculture [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	2,054	1,632	1,547
Provision for loan losses	1,780	520	85
Charge-offs	0	(98)	0
Recoveries	0	0	0
Net charge-offs	0	(98)	0
Ending balance	3,834	2,054	1,632
Period-end amount allocated to [Abstract]
Loans individually evaluated for impairment	2,093	0	0
Loans collectively evaluated for impairment	1,741	2,054	1,632
Ending balance	3,834	2,054	1,632
Loans individually and collectively evaluated for impairment [Abstract]
Loans individually evaluated for impairment	9,130	0	4,830
Loans collectively evaluated for impairment	85,918	115,751	118,796
Ending balance	95,048	115,751	123,626
Residential Mortgage [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	466	643	628
Provision for loan losses	169	(251)	(19)
Charge-offs	0	0	0
Recoveries	0	74	34
Net charge-offs	0	74	34
Ending balance	635	466	643
Period-end amount allocated to [Abstract]
Loans individually evaluated for impairment	159	171	287
Loans collectively evaluated for impairment	476	295	356
Ending balance	635	466	643
Loans individually and collectively evaluated for impairment [Abstract]
Loans individually evaluated for impairment	1,036	1,084	1,551
Loans collectively evaluated for impairment	63,461	63,859	49,513
Ending balance	64,497	64,943	51,064
Residential Construction [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	201	318	360
Provision for loan losses	(73)	(138)	(173)
Charge-offs	0	0	0
Recoveries	0	21	131
Net charge-offs	0	21	131
Ending balance	128	201	318
Period-end amount allocated to [Abstract]
Loans individually evaluated for impairment	83	56	49
Loans collectively evaluated for impairment	45	145	269
Ending balance	128	201	318
Loans individually and collectively evaluated for impairment [Abstract]
Loans individually evaluated for impairment	652	691	560
Loans collectively evaluated for impairment	3,571	14,521	19,564
Ending balance	4,223	15,212	20,124
Consumer [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	236	279	342
Provision for loan losses	(43)	(9)	(92)
Charge-offs	(15)	(43)	(34)
Recoveries	36	9	63
Net charge-offs	21	(34)	29
Ending balance	214	236	279
Period-end amount allocated to [Abstract]
Loans individually evaluated for impairment	1	1	2
Loans collectively evaluated for impairment	213	235	277
Ending balance	214	236	279
Loans individually and collectively evaluated for impairment [Abstract]
Loans individually evaluated for impairment	754	333	389
Loans collectively evaluated for impairment	18,713	26,492	35,008
Ending balance	19,467	26,825	35,397
Unallocated [Member]
Allowance for loan losses [Roll Forward]
Beginning balance	199	862	171
Provision for loan losses	239	(663)	691
Charge-offs	0	0	0
Recoveries	0	0	0
Net charge-offs	0	0	0
Ending balance	438	199	862
Period-end amount allocated to [Abstract]
Loans individually evaluated for impairment	0	0	0
Loans collectively evaluated for impairment	438	199	862
Ending balance	$ 438	$ 199	$ 862

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Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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Amount, after recoveries, of loans and leases that have been written-off.

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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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The balance of financing receivables that were collectively evaluated for impairment.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Amount of expense related to estimated loss from loan and lease transactions.

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