Loans, Impaired Financing Receivable (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	$ 19,559		$ 19,559		$ 21,220
Impaired Financing Receivable, Recorded Investment [Abstract]
Recorded Investment With No Allowance	12,906		12,906		14,865
Recorded Investment With Allowance	4,862		4,862		4,807
Total Recorded Investment	17,768		17,768		19,672
Related Allowance	791		791		735
Impaired Financing Receivable, Average Recorded Investment [Abstract]
Average Recorded Investment	16,997	$ 21,377	18,729	$ 21,528
Interest Income Recognized	102	122	380	424
Interest Income Recognized Cash Basis	18	0	20	11
Real Estate Loans [Member] \| Mortgages [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	1,125		1,125		1,212
Impaired Financing Receivable, Recorded Investment [Abstract]
Recorded Investment With No Allowance	609		609		794
Recorded Investment With Allowance	296		296		223
Total Recorded Investment	905		905		1,017
Related Allowance	20		20		20
Impaired Financing Receivable, Average Recorded Investment [Abstract]
Average Recorded Investment	900	1,048	998	1,075
Interest Income Recognized	5	3	15	12
Interest Income Recognized Cash Basis	0	0	0	0
Real Estate Loans [Member] \| Home Equity [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	159		159		170
Impaired Financing Receivable, Recorded Investment [Abstract]
Recorded Investment With No Allowance	77		77		83
Recorded Investment With Allowance	59		59		66
Total Recorded Investment	136		136		149
Related Allowance	9		9		12
Impaired Financing Receivable, Average Recorded Investment [Abstract]
Average Recorded Investment	138	143	142	108
Interest Income Recognized	2	2	5	4
Interest Income Recognized Cash Basis	0	0	0	0
Real Estate Loans [Member] \| Commercial [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	10,053		10,053		12,070
Impaired Financing Receivable, Recorded Investment [Abstract]
Recorded Investment With No Allowance	8,325		8,325		10,723
Recorded Investment With Allowance	1,140		1,140		814
Total Recorded Investment	9,465		9,465		11,537
Related Allowance	341		341		251
Impaired Financing Receivable, Average Recorded Investment [Abstract]
Average Recorded Investment	9,436	11,906	10,836	11,768
Interest Income Recognized	75	112	294	342
Interest Income Recognized Cash Basis	18	0	20	11
Real Estate Loans [Member] \| Agricultural [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	4,614		4,614		3,900
Impaired Financing Receivable, Recorded Investment [Abstract]
Recorded Investment With No Allowance	2,526		2,526		1,580
Recorded Investment With Allowance	1,872		1,872		2,202
Total Recorded Investment	4,398		4,398		3,782
Related Allowance	79		79		151
Impaired Financing Receivable, Average Recorded Investment [Abstract]
Average Recorded Investment	3,633	4,795	3,718	5,068
Interest Income Recognized	18	5	58	61
Interest Income Recognized Cash Basis	0	0	0	0
Consumer [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	15		15		4
Impaired Financing Receivable, Recorded Investment [Abstract]
Recorded Investment With No Allowance	3		3		4
Recorded Investment With Allowance	12		12		0
Total Recorded Investment	15		15		4
Related Allowance	12		12		0
Impaired Financing Receivable, Average Recorded Investment [Abstract]
Average Recorded Investment	5	4	3	2
Interest Income Recognized	0	0	0	0
Interest Income Recognized Cash Basis	0	0	0	0
Other Commercial Loans [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	2,225		2,225		2,517
Impaired Financing Receivable, Recorded Investment [Abstract]
Recorded Investment With No Allowance	1,243		1,243		1,555
Recorded Investment With Allowance	360		360		347
Total Recorded Investment	1,603		1,603		1,902
Related Allowance	181		181		147
Impaired Financing Receivable, Average Recorded Investment [Abstract]
Average Recorded Investment	1,626	2,073	1,757	2,088
Interest Income Recognized	0	0	2	1
Interest Income Recognized Cash Basis	0	0	0	0
Other Agricultural Loans [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	1,368		1,368		1,347
Impaired Financing Receivable, Recorded Investment [Abstract]
Recorded Investment With No Allowance	123		123		126
Recorded Investment With Allowance	1,123		1,123		1,155
Total Recorded Investment	1,246		1,246		1,281
Related Allowance	149		149		$ 154
Impaired Financing Receivable, Average Recorded Investment [Abstract]
Average Recorded Investment	1,259	1,408	1,275	1,419
Interest Income Recognized	2	0	6	4
Interest Income Recognized Cash Basis	$ 0	$ 0	$ 0	$ 0

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5212-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5258-111524

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-Publisher FASB
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-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953550-111524

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Amount of allowance for credit losses related to recorded investment.

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