LOANS AND ALLOWANCE FOR LOAN LOSSES - Troubled Debt Restructuring (Details)	12 Months Ended
Dec. 31, 2017 USD ($) contract	Dec. 31, 2016 USD ($) contract
Financing Receivable, Modifications [Line Items]
Total	$ 657,000	$ 505,000
Specific reserves on TDRs	$ 17,000	$ 4,000
Troubled Debt Restructurings:
Number of Contracts \| contract	3,000	4,000
Pre-Modification Outstanding Recorded Investment	$ 392,000	$ 338,000
Post-Modification Outstanding Recorded Investment	375,000	334,000
Increase in allowance for loan losses due to TDRs	0	0
Troubled debt restructuring charge-offs	$ 0	$ 0
Commercial and industrial
Troubled Debt Restructurings:
Number of Contracts \| contract	2,000	1,000
Pre-Modification Outstanding Recorded Investment	$ 381,000	$ 90,000
Post-Modification Outstanding Recorded Investment	$ 364,000	$ 90,000
Commercial real estate
Troubled Debt Restructurings:
Number of Contracts \| contract
Pre-Modification Outstanding Recorded Investment	$ 0
Post-Modification Outstanding Recorded Investment	$ 0
Consumer
Troubled Debt Restructurings:
Number of Contracts \| contract	0
Pre-Modification Outstanding Recorded Investment	$ 0
Post-Modification Outstanding Recorded Investment	$ 0
1-4 family residential
Troubled Debt Restructurings:
Number of Contracts \| contract	1,000	3,000
Pre-Modification Outstanding Recorded Investment	$ 11,000	$ 248,000
Post-Modification Outstanding Recorded Investment	$ 11,000	244,000
Farmland
Troubled Debt Restructurings:
Number of Contracts \| contract	0
Pre-Modification Outstanding Recorded Investment	$ 0
Post-Modification Outstanding Recorded Investment	$ 0
Multi-family residential
Troubled Debt Restructurings:
Number of Contracts \| contract	0
Pre-Modification Outstanding Recorded Investment	$ 0
Post-Modification Outstanding Recorded Investment	$ 0
Agricultural
Troubled Debt Restructurings:
Number of Contracts \| contract	0
Pre-Modification Outstanding Recorded Investment	$ 0
Post-Modification Outstanding Recorded Investment	0
Nonaccrual TDRs
Financing Receivable, Modifications [Line Items]
Total	0	43,000
Performing TDRs
Financing Receivable, Modifications [Line Items]
Total	$ 657,000	$ 462,000

Financing Receivables, Impaired, Troubled Debt Restructuring, Increase in Allowance for Loan Losses

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Troubled Debt Restructuring [Abstract]

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No definition available.

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Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524

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The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=82895541&loc=d3e18845-111554

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Reflects the amount of the write-down related to a troubled debt restructuring.

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