Loans, Impaired Financing Receivable (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	$ 19,192		$ 19,050
Impaired Financing Receivable, Recorded Investment [Abstract]
Recorded Investment With No Allowance	12,885		13,047
Recorded Investment With Allowance	4,212		4,230
Total Recorded Investment	17,097		17,277
Related Allowance	485		510
Impaired Financing Receivable, Average Recorded Investment [Abstract]
Average Recorded Investment	17,028	$ 19,558
Interest Income Recognized	98	135
Interest Income Recognized Cash Basis	7	2
Real Estate Loans [Member] \| Mortgages [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	1,059		1,070
Impaired Financing Receivable, Recorded Investment [Abstract]
Recorded Investment With No Allowance	724		740
Recorded Investment With Allowance	122		123
Total Recorded Investment	846		863
Related Allowance	9		9
Impaired Financing Receivable, Average Recorded Investment [Abstract]
Average Recorded Investment	851	1,031
Interest Income Recognized	5	5
Interest Income Recognized Cash Basis	0	0
Real Estate Loans [Member] \| Home Equity [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	147		150
Impaired Financing Receivable, Recorded Investment [Abstract]
Recorded Investment With No Allowance	69		70
Recorded Investment With Allowance	54		57
Total Recorded Investment	123		127
Related Allowance	8		9
Impaired Financing Receivable, Average Recorded Investment [Abstract]
Average Recorded Investment	124	146
Interest Income Recognized	1	2
Interest Income Recognized Cash Basis	0	0
Real Estate Loans [Member] \| Commercial [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	10,100		9,847
Impaired Financing Receivable, Recorded Investment [Abstract]
Recorded Investment With No Allowance	8,408		8,323
Recorded Investment With Allowance	913		860
Total Recorded Investment	9,321		9,183
Related Allowance	101		95
Impaired Financing Receivable, Average Recorded Investment [Abstract]
Average Recorded Investment	9,238	11,486
Interest Income Recognized	67	104
Interest Income Recognized Cash Basis	7	2
Real Estate Loans [Member] \| Agricultural [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	4,791		4,811
Impaired Financing Receivable, Recorded Investment [Abstract]
Recorded Investment With No Allowance	2,777		2,799
Recorded Investment With Allowance	1,784		1,846
Total Recorded Investment	4,561		4,645
Related Allowance	12		83
Impaired Financing Receivable, Average Recorded Investment [Abstract]
Average Recorded Investment	4,590	3,777
Interest Income Recognized	22	21
Interest Income Recognized Cash Basis	0	0
Consumer [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	1		2
Impaired Financing Receivable, Recorded Investment [Abstract]
Recorded Investment With No Allowance	1		2
Recorded Investment With Allowance	0		0
Total Recorded Investment	1		2
Related Allowance	0		0
Impaired Financing Receivable, Average Recorded Investment [Abstract]
Average Recorded Investment	1	3
Interest Income Recognized	0	0
Interest Income Recognized Cash Basis	0	0
Other Commercial Loans [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	1,793		1,908
Impaired Financing Receivable, Recorded Investment [Abstract]
Recorded Investment With No Allowance	889		1,094
Recorded Investment With Allowance	238		241
Total Recorded Investment	1,127		1,335
Related Allowance	170		170
Impaired Financing Receivable, Average Recorded Investment [Abstract]
Average Recorded Investment	1,121	1,839
Interest Income Recognized	1	1
Interest Income Recognized Cash Basis	0	0
Other Agricultural Loans [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	1,301		1,262
Impaired Financing Receivable, Recorded Investment [Abstract]
Recorded Investment With No Allowance	17		19
Recorded Investment With Allowance	1,101		1,103
Total Recorded Investment	1,118		1,122
Related Allowance	185		$ 144
Impaired Financing Receivable, Average Recorded Investment [Abstract]
Average Recorded Investment	1,103	1,276
Interest Income Recognized	2	2
Interest Income Recognized Cash Basis	$ 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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Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-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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Amount of investment in impaired financing receivables for which there is no related allowance for credit losses.

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Amount of investment in impaired financing receivables for which there is a related allowance for credit losses.

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