Loans, Impaired Financing Receivable (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	$ 21,202		$ 21,202		$ 21,220
Recorded Investment With No Allowance	14,483		14,483		14,865
Recorded Investment With Allowance	5,040		5,040		4,807
Total Recorded Investment	19,523		19,523		19,672
Related Allowance	888		888		735
Average Recorded Investment	19,619	$ 20,326	19,589	$ 21,603
Interest Income Recognized	143	143	278	302
Interest Income Recognized Cash Basis	0	5	2	11
Real Estate Loans [Member] \| Mortgages [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	1,272		1,272		1,212
Recorded Investment With No Allowance	756		756		794
Recorded Investment With Allowance	297		297		223
Total Recorded Investment	1,053		1,053		1,017
Related Allowance	20		20		20
Average Recorded Investment	1,062	1,073	1,047	1,088
Interest Income Recognized	5	5	10	9
Interest Income Recognized Cash Basis	0	0	0	0
Real Estate Loans [Member] \| Home Equity [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	163		163		170
Recorded Investment With No Allowance	79		79		83
Recorded Investment With Allowance	62		62		66
Total Recorded Investment	141		141		149
Related Allowance	10		10		12
Average Recorded Investment	142	95	144	90
Interest Income Recognized	1	1	3	2
Interest Income Recognized Cash Basis	0	0	0	0
Real Estate Loans [Member] \| Commercial [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	12,402		12,402		12,070
Recorded Investment With No Allowance	10,613		10,613		10,723
Recorded Investment With Allowance	1,216		1,216		814
Total Recorded Investment	11,829		11,829		11,537
Related Allowance	452		452		251
Average Recorded Investment	11,572	10,849	11,529	11,699
Interest Income Recognized	115	111	219	230
Interest Income Recognized Cash Basis	0	5	2	11
Real Estate Loans [Member] \| Agricultural [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	3,628		3,628		3,900
Recorded Investment With No Allowance	1,535		1,535		1,580
Recorded Investment With Allowance	1,935		1,935		2,202
Total Recorded Investment	3,470		3,470		3,782
Related Allowance	77		77		151
Average Recorded Investment	3,746	4,835	3,761	5,205
Interest Income Recognized	19	24	40	56
Interest Income Recognized Cash Basis	0	0	0	0
Consumer [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance					4
Recorded Investment With No Allowance					4
Recorded Investment With Allowance					0
Total Recorded Investment					4
Related Allowance					0
Average Recorded Investment	2	2	3	1
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	2,360		2,360		2,517
Recorded Investment With No Allowance	1,375		1,375		1,555
Recorded Investment With Allowance	366		366		347
Total Recorded Investment	1,741		1,741		1,902
Related Allowance	175		175		147
Average Recorded Investment	1,805	2,056	1,822	2,096
Interest Income Recognized	1	0	2	1
Interest Income Recognized Cash Basis	0	0	0	0
Other Agricultural Loans [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	1,377		1,377		1,347
Recorded Investment With No Allowance	125		125		126
Recorded Investment With Allowance	1,164		1,164		1,155
Total Recorded Investment	1,289		1,289		1,281
Related Allowance	154		154		$ 154
Average Recorded Investment	1,290	1,416	1,283	1,424
Interest Income Recognized	2	2	4	4
Interest Income Recognized Cash Basis	$ 0	$ 0	$ 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=121611835&loc=d3e5212-111524

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-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.

+ 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.

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

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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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