LOANS AND ALLOWANCE FOR LOAN LOSSES - Troubled Debt Restructuring (Details)	9 Months Ended
Sep. 30, 2017 USD ($) contract	Sep. 30, 2016 USD ($) contract	Dec. 31, 2016 USD ($)
Financing Receivable, Modifications [Line Items]
Total	$ 316,000		$ 505,000
Specific reserves on TDRs	$ 19,000		4,000
Troubled Debt Restructurings:
Number of Contracts \| contract	2	4
Pre-Modification Outstanding Recorded Investment	$ 45,000	$ 1,075,000
Post-Modification Outstanding Recorded Investment	26,000	1,075,000
Increase in allowance for loan losses due to TDRs	19,000	0
Troubled debt restructuring charge-offs	$ 0	$ 0
Commercial and industrial
Troubled Debt Restructurings:
Number of Contracts \| contract	1	1
Pre-Modification Outstanding Recorded Investment	$ 34,000	$ 90,000
Post-Modification Outstanding Recorded Investment	$ 15,000	$ 90,000
1-4 family residential
Troubled Debt Restructurings:
Number of Contracts \| contract	1	2
Pre-Modification Outstanding Recorded Investment	$ 11,000	$ 189,000
Post-Modification Outstanding Recorded Investment	11,000	$ 189,000
Commercial real estate
Troubled Debt Restructurings:
Number of Contracts \| contract		1
Pre-Modification Outstanding Recorded Investment		$ 796,000
Post-Modification Outstanding Recorded Investment		$ 796,000
Nonaccrual TDRs
Financing Receivable, Modifications [Line Items]
Total	0		43,000
Performing TDRs
Financing Receivable, Modifications [Line Items]
Total	$ 316,000		$ 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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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.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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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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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- Definition

The amount of the outstanding recorded investment related to 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 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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