Loans, Impaired Financing Receivable (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	$ 23,037		$ 23,037		$ 27,160
Recorded Investment With No Allowance	14,968		14,968		16,802
Recorded Investment With Allowance	6,553		6,553		6,648
Total Recorded Investment	21,521		21,521		23,450
Related Allowance	803		803		676
Average Recorded Investment	20,326	$ 24,567	21,603	$ 24,554
Interest Income Recognized	143	208	302	422
Interest Income Recognized Cash Basis	5	3	11	8
Real Estate Loans [Member] \| Mortgages [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	1,228		1,228		932
Recorded Investment With No Allowance	832		832		515
Recorded Investment With Allowance	233		233		288
Total Recorded Investment	1,065		1,065		803
Related Allowance	10		10		10
Average Recorded Investment	1,073	1,045	1,088	1,034
Interest Income Recognized	5	3	9	7
Interest Income Recognized Cash Basis	0	0	0	0
Real Estate Loans [Member] \| Home Equity [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	269		269		106
Recorded Investment With No Allowance	50		50		12
Recorded Investment With Allowance	71		71		75
Total Recorded Investment	121		121		87
Related Allowance	13		13		14
Average Recorded Investment	95	95	90	101
Interest Income Recognized	1	1	2	2
Interest Income Recognized Cash Basis	0	0	0	0
Real Estate Loans [Member] \| Commercial [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	12,510		12,510		16,326
Recorded Investment With No Allowance	10,517		10,517		11,933
Recorded Investment With Allowance	1,452		1,452		1,394
Total Recorded Investment	11,969		11,969		13,327
Related Allowance	333		333		216
Average Recorded Investment	10,849	13,833	11,699	13,814
Interest Income Recognized	111	120	230	242
Interest Income Recognized Cash Basis	5	3	11	8
Real Estate Loans [Member] \| Agricultural [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	4,842		4,842		5,598
Recorded Investment With No Allowance	1,641		1,641		2,386
Recorded Investment With Allowance	3,175		3,175		3,206
Total Recorded Investment	4,816		4,816		5,592
Related Allowance	146		146		84
Average Recorded Investment	4,835	4,185	5,205	4,135
Interest Income Recognized	24	49	56	100
Interest Income Recognized Cash Basis	0	0	0	0
Real Estate Loans [Member] \| Construction [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	0		0		0
Recorded Investment With No Allowance	0		0		0
Recorded Investment With Allowance	0		0		0
Total Recorded Investment	0		0		0
Related Allowance	0		0		0
Average Recorded Investment	0	0	0	0
Interest Income Recognized	0	0	0	0
Interest Income Recognized Cash Basis	0	0	0	0
Consumer [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	5		5		0
Recorded Investment With No Allowance	5		5		0
Recorded Investment With Allowance	0		0		0
Total Recorded Investment	5		5		0
Related Allowance	0		0		0
Average Recorded Investment	2	0	1	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	2,715		2,715		2,711
Recorded Investment With No Allowance	1,821		1,821		1,836
Recorded Investment With Allowance	313		313		370
Total Recorded Investment	2,134		2,134		2,206
Related Allowance	143		143		193
Average Recorded Investment	2,056	4,067	2,096	4,112
Interest Income Recognized	0	26	1	52
Interest Income Recognized Cash Basis	0	0	0	0
Other Agricultural Loans [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	1,468		1,468		1,487
Recorded Investment With No Allowance	102		102		120
Recorded Investment With Allowance	1,309		1,309		1,315
Total Recorded Investment	1,411		1,411		1,435
Related Allowance	158		158		159
Average Recorded Investment	1,416	1,342	1,424	1,356
Interest Income Recognized	2	9	4	19
Interest Income Recognized Cash Basis	0	0	0	0
State and Political Subdivision Loans [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	0		0		0
Recorded Investment With No Allowance	0		0		0
Recorded Investment With Allowance	0		0		0
Total Recorded Investment	0		0		0
Related Allowance	0		0		$ 0
Average Recorded Investment	0	0	0	0
Interest Income Recognized	0	0	0	0
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.

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-Publisher FASB
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-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
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-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 no related allowance for credit losses.

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