LOANS AND ALLOWANCE FOR LOAN LOSSES - Troubled Debt Restructuring (Details)	9 Months Ended	12 Months Ended
Sep. 30, 2018 USD ($) contract	Sep. 30, 2017 USD ($) contract	Dec. 31, 2017 USD ($) contract
Financing Receivable, Modifications [Line Items]
Total	$ 727,000		$ 657,000
Specific reserves on TDRs	$ 11,000		$ 17,000
Troubled Debt Restructurings:
Number of Contracts \| contract	2	2	3
Pre-Modification Outstanding Recorded Investment	$ 93,000	$ 45,000	$ 392,000
Post-Modification Outstanding Recorded Investment	$ 93,000	26,000	$ 375,000
Increase in allowance for loan losses due to TDRs		0
Troubled debt restructuring charge-offs		$ 0
Commercial and industrial
Troubled Debt Restructurings:
Number of Contracts \| contract		1	2
Pre-Modification Outstanding Recorded Investment		$ 34,000	$ 381,000
Post-Modification Outstanding Recorded Investment		$ 15,000	$ 364,000
1-4 family residential
Troubled Debt Restructurings:
Number of Contracts \| contract	1	1	1
Pre-Modification Outstanding Recorded Investment	$ 15,000	$ 11,000	$ 11,000
Post-Modification Outstanding Recorded Investment	$ 15,000	$ 11,000	11,000
Farmland
Troubled Debt Restructurings:
Number of Contracts \| contract	1
Pre-Modification Outstanding Recorded Investment	$ 78,000
Post-Modification Outstanding Recorded Investment	78,000
Nonaccrual TDRs
Financing Receivable, Modifications [Line Items]
Total	0		0
Performing TDRs
Financing Receivable, Modifications [Line Items]
Total	$ 727,000		$ 657,000

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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Amount of allowance for credit losses related to receivables which had been measured under a general allowance for credit losses methodology that are now identified as troubled debt restructurings.

+ References

No definition available.

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
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Post-modification amount of investment in financing receivables modified by troubled debt restructurings.

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Pre-modification amount of investment in financing receivables modified by troubled debt restructurings.

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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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-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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