LOANS AND ALLOWANCE FOR LOAN LOSSES - Nonaccrual and loans past due over 90 days - (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Recorded investment in nonaccrual and loans past due over 90 days still on accrual and aging of recorded investment in past due
Non-accrual loans	$ 15,895	$ 15,808
Past due over 90 days and still accruing	265	2,135
Commercial \| Commercial and industrial
Recorded investment in nonaccrual and loans past due over 90 days still on accrual and aging of recorded investment in past due
Non-accrual loans	1,890	882
Commercial \| Agricultural
Recorded investment in nonaccrual and loans past due over 90 days still on accrual and aging of recorded investment in past due
Non-accrual loans	1,471	1,631
Commercial real estate \| Farm
Recorded investment in nonaccrual and loans past due over 90 days still on accrual and aging of recorded investment in past due
Non-accrual loans	861	1,347
Commercial real estate \| Hotel
Recorded investment in nonaccrual and loans past due over 90 days still on accrual and aging of recorded investment in past due
Non-accrual loans		64
Commercial real estate \| Construction and development
Recorded investment in nonaccrual and loans past due over 90 days still on accrual and aging of recorded investment in past due
Non-accrual loans		122
Past due over 90 days and still accruing		2,135
Commercial real estate \| Other
Recorded investment in nonaccrual and loans past due over 90 days still on accrual and aging of recorded investment in past due
Non-accrual loans	3,722	3,219
Residential \| 1-4 family
Recorded investment in nonaccrual and loans past due over 90 days still on accrual and aging of recorded investment in past due
Non-accrual loans	6,365	7,163
Past due over 90 days and still accruing	265
Residential \| Home equity
Recorded investment in nonaccrual and loans past due over 90 days still on accrual and aging of recorded investment in past due
Non-accrual loans	635	1,273
Consumer \| Direct
Recorded investment in nonaccrual and loans past due over 90 days still on accrual and aging of recorded investment in past due
Non-accrual loans	$ 951	$ 107

Recorded investment in financing receivables that are 90 days or more past due and still accruing.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5111-111524

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