Loans, Impaired Financing Receivable (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	$ 22,762		$ 22,762		$ 27,160
Recorded Investment With No Allowance	14,804		14,804		16,802
Recorded Investment With Allowance	6,548		6,548		6,648
Total Recorded Investment	21,352		21,352		23,450
Related Allowance	810		810		676
Average Recorded Investment	21,377	$ 25,198	21,528	$ 24,769
Interest Income Recognized	122	182	424	604
Interest Income Recognized Cash Basis	0	6	11	14
Real Estate Loans [Member] \| Mortgages [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	1,220		1,220		932
Recorded Investment With No Allowance	814		814		515
Recorded Investment With Allowance	227		227		288
Total Recorded Investment	1,041		1,041		803
Related Allowance	10		10		10
Average Recorded Investment	1,048	896	1,075	988
Interest Income Recognized	3	3	12	10
Interest Income Recognized Cash Basis	0	0	0	0
Real Estate Loans [Member] \| Home Equity [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	174		174		106
Recorded Investment With No Allowance	85		85		12
Recorded Investment With Allowance	69		69		75
Total Recorded Investment	154		154		87
Related Allowance	12		12		14
Average Recorded Investment	143	92	108	98
Interest Income Recognized	2	2	4	4
Interest Income Recognized Cash Basis	0	0	0	0
Real Estate Loans [Member] \| Commercial [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	12,466		12,466		16,326
Recorded Investment With No Allowance	10,469		10,469		11,933
Recorded Investment With Allowance	1,452		1,452		1,394
Total Recorded Investment	11,921		11,921		13,327
Related Allowance	342		342		216
Average Recorded Investment	11,906	14,116	11,768	13,915
Interest Income Recognized	112	130	342	372
Interest Income Recognized Cash Basis	0	6	11	14
Real Estate Loans [Member] \| Agricultural [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	4,811		4,811		5,598
Recorded Investment With No Allowance	1,617		1,617		2,386
Recorded Investment With Allowance	3,164		3,164		3,206
Total Recorded Investment	4,781		4,781		5,592
Related Allowance	145		145		84
Average Recorded Investment	4,795	5,146	5,068	4,472
Interest Income Recognized	5	24	61	124
Interest Income Recognized Cash Basis	0	0	0	0
Consumer [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	6		6		0
Recorded Investment With No Allowance	6		6		0
Recorded Investment With Allowance	0		0		0
Total Recorded Investment	6		6		0
Related Allowance	0		0		0
Average Recorded Investment	4	0	2	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	2,621		2,621		2,711
Recorded Investment With No Allowance	1,715		1,715		1,836
Recorded Investment With Allowance	327		327		370
Total Recorded Investment	2,042		2,042		2,206
Related Allowance	144		144		193
Average Recorded Investment	2,073	3,495	2,088	3,906
Interest Income Recognized	0	21	1	73
Interest Income Recognized Cash Basis	0	0	0	0
Other Agricultural Loans [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	1,464		1,464		1,487
Recorded Investment With No Allowance	98		98		120
Recorded Investment With Allowance	1,309		1,309		1,315
Total Recorded Investment	1,407		1,407		1,435
Related Allowance	157		157		$ 159
Average Recorded Investment	1,408	1,453	1,419	1,388
Interest Income Recognized	0	2	4	21
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=118936363&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=118936363&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
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-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.

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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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