LOANS AND RELATED ALLOWANCE FOR LOAN LOSSES, Impaired Financing Receivable (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	$ 28,887	$ 20,127
Recorded Investment With No Allowance	21,756	15,031
Recorded Investment With Allowance	2,642	2,662
Total Recorded Investment	24,398	17,693
Related Allowance	410	487
Average Recorded Investment	22,392	12,874	$ 8,804
Interest Income Recognized	750	201	180
Interest Income Recognized Cash Basis	59	7	11
Real Estate Loans [Member] \| Mortgages [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	1,055	953
Recorded Investment With No Allowance	273	570
Recorded Investment With Allowance	700	330
Total Recorded Investment	973	900
Related Allowance	47	22
Average Recorded Investment	900	590	240
Interest Income Recognized	13	13	12
Interest Income Recognized Cash Basis	0	0	0
Real Estate Loans [Member] \| Home Equity [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	92	57
Recorded Investment With No Allowance	40	0
Recorded Investment With Allowance	52	57
Total Recorded Investment	92	57
Related Allowance	9	10
Average Recorded Investment	67	59	88
Interest Income Recognized	4	4	4
Interest Income Recognized Cash Basis	0	0	0
Real Estate Loans [Member] \| Commercial [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	16,363	7,958
Recorded Investment With No Allowance	13,154	5,697
Recorded Investment With Allowance	710	45
Total Recorded Investment	13,864	5,742
Related Allowance	94	45
Average Recorded Investment	11,567	5,959	5,683
Interest Income Recognized	385	69	63
Interest Income Recognized Cash Basis	7	1	5
Real Estate Loans [Member] \| Agricultural [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	5,231	3,347
Recorded Investment With No Allowance	3,283	2,000
Recorded Investment With Allowance	618	1,347
Total Recorded Investment	3,901	3,347
Related Allowance	3	54
Average Recorded Investment	3,574	361	56
Interest Income Recognized	131	17	2
Interest Income Recognized Cash Basis	0	0	0
Consumer [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	10
Recorded Investment With No Allowance	2
Recorded Investment With Allowance	6
Total Recorded Investment	8
Related Allowance	0
Average Recorded Investment	3	0	0
Interest Income Recognized	0	0	0
Interest Income Recognized Cash Basis	0	0	0
Other Commercial Loans [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	4,739	6,159
Recorded Investment With No Allowance	3,766	5,135
Recorded Investment With Allowance	431	859
Total Recorded Investment	4,197	5,994
Related Allowance	231	326
Average Recorded Investment	4,790	5,715	2,700
Interest Income Recognized	152	87	98
Interest Income Recognized Cash Basis	52	6	6
Other Agricultural Loans [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	1,397	1,653
Recorded Investment With No Allowance	1,238	1,629
Recorded Investment With Allowance	125	24
Total Recorded Investment	1,363	1,653
Related Allowance	26	30
Average Recorded Investment	1,491	190	37
Interest Income Recognized	65	11	1
Interest Income Recognized Cash Basis	$ 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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=84173941&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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+ References

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84173941&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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