Loans, Impaired Financing Receivable (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	$ 21,337		$ 21,220
Recorded Investment With No Allowance	14,704		14,865
Recorded Investment With Allowance	5,027		4,807
Total Recorded Investment	19,731		19,672
Related Allowance	753		735
Average Recorded Investment	19,558	$ 22,879
Interest Income Recognized	135	159
Interest Income Recognized Cash Basis	2	6
Real Estate Loans [Member] \| Mortgages [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	1,282		1,212
Recorded Investment With No Allowance	776		794
Recorded Investment With Allowance	300		223
Total Recorded Investment	1,076		1,017
Related Allowance	20		20
Average Recorded Investment	1,031	1,103
Interest Income Recognized	5	4
Interest Income Recognized Cash Basis	0	0
Real Estate Loans [Member] \| Home Equity [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	166		170
Recorded Investment With No Allowance	80		83
Recorded Investment With Allowance	64		66
Total Recorded Investment	144		149
Related Allowance	11		12
Average Recorded Investment	146	85
Interest Income Recognized	2	1
Interest Income Recognized Cash Basis	0	0
Real Estate Loans [Member] \| Commercial [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	12,000		12,070
Recorded Investment With No Allowance	10,668		10,723
Recorded Investment With Allowance	812		814
Total Recorded Investment	11,480		11,537
Related Allowance	335		251
Average Recorded Investment	11,486	12,548
Interest Income Recognized	104	119
Interest Income Recognized Cash Basis	2	6
Real Estate Loans [Member] \| Agricultural [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	4,046		3,900
Recorded Investment With No Allowance	1,549		1,580
Recorded Investment With Allowance	2,344		2,202
Total Recorded Investment	3,893		3,782
Related Allowance	86		151
Average Recorded Investment	3,777	5,575
Interest Income Recognized	21	32
Interest Income Recognized Cash Basis	0	0
Consumer [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	3		4
Recorded Investment With No Allowance	3		4
Recorded Investment With Allowance	0		0
Total Recorded Investment	3		4
Related Allowance	0		0
Average Recorded Investment	3	0
Interest Income Recognized	0	0
Interest Income Recognized Cash Basis	0	0
Other Commercial Loans [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	2,459		2,517
Recorded Investment With No Allowance	1,499		1,555
Recorded Investment With Allowance	343		347
Total Recorded Investment	1,842		1,902
Related Allowance	148		147
Average Recorded Investment	1,839	2,137
Interest Income Recognized	1	1
Interest Income Recognized Cash Basis	0	0
Other Agricultural Loans [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	1,381		1,347
Recorded Investment With No Allowance	129		126
Recorded Investment With Allowance	1,164		1,155
Total Recorded Investment	1,293		1,281
Related Allowance	153		$ 154
Average Recorded Investment	1,276	1,431
Interest Income Recognized	2	2
Interest Income Recognized Cash Basis	$ 0	$ 0

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- Definition

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

+ References

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=118936363&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=118936363&loc=d3e5258-111524

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- Definition

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.

+ References

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Amount of interest income recognized on a cash-basis method of accounting that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

+ References

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+ References

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=118936363&loc=SL6953550-111524

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Amount of allowance for credit losses related to recorded investment.

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Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without related allowance for credit losses.

+ References

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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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