LOANS AND ALLOWANCE - Loan Impairment average balance of impaired loans and interest income and cash basis interest - (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Interest Income Recognized
Interest Income Recognized	$ 55	$ 71	$ 212	$ 269
Cash Basis Income Recognized
Cash Basis Income Recognized	55	71	212	269
Average recorded investment
Average Balance	23,026	19,177	22,244	17,300
Commercial \| Commercial and industrial
Interest Income Recognized
Interest Income Recognized	8	12	70	43
Cash Basis Income Recognized
Cash Basis Income Recognized	8	12	70	43
Average recorded investment
Average Balance	1,358	725	1,041	753
Commercial \| Agricultural
Average recorded investment
Average Balance	1,622	1,640	1,701	824
Commercial real estate
Average recorded investment
Average Balance				155
Commercial real estate \| Farm
Average recorded investment
Average Balance	1,656	1,357	1,588	830
Commercial real estate \| Hotel
Average recorded investment
Average Balance	2,934	32	2,229	16
Commercial real estate \| Construction and development
Average recorded investment
Average Balance	746	124	804
Commercial real estate \| Other
Interest Income Recognized
Interest Income Recognized	9	35	83	152
Cash Basis Income Recognized
Cash Basis Income Recognized	9	35	83	152
Average recorded investment
Average Balance	4,984	4,791	4,641	4,898
Residential \| 1-4 family
Interest Income Recognized
Interest Income Recognized	32	17	41	44
Cash Basis Income Recognized
Cash Basis Income Recognized	32	17	41	44
Average recorded investment
Average Balance	7,128	8,299	7,652	7,433
Residential \| Home equity
Interest Income Recognized
Interest Income Recognized	5	4	15	20
Cash Basis Income Recognized
Cash Basis Income Recognized	5	4	15	20
Average recorded investment
Average Balance	1,624	2,083	1,811	2,270
Consumer \| Direct
Interest Income Recognized
Interest Income Recognized	1	3	3	9
Cash Basis Income Recognized
Cash Basis Income Recognized	1	3	3	9
Average recorded investment
Average Balance	$ 974	$ 126	$ 777	121
Consumer \| Indirect
Interest Income Recognized
Interest Income Recognized				1
Cash Basis Income Recognized
Cash Basis Income Recognized				$ 1

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

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=66008989&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=66008989&loc=d3e5258-111524

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