COMMITMENTS AND CONTINGENCIES - Life Insurance and Control Agreements (Details) - USD ($)	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Share Repurchase Plan
Share repurchase program authorized amount	$ 250,000
Stock repurchased in open market transactions (in shares)	8,581
Stock repurchased in open market transactions	$ 30,340
Authorized balance remaining under share repurchase program	219,659
Maximum
Commitment and contingencies
Professional outplacement services that would be received by the participants	$ 10,000
2002 Plan
Commitment and contingencies
Period of graded vesting schedule	5 years
Annual vesting by the participants (as a percent)	20.00%
Expenses incurred	$ 207,000	$ 327,000
2002 Plan \| Officer participants
Commitment and contingencies
Bonus to be paid as a percentage of the participants base annual salary	15.00%
2002 Plan \| Other participants
Commitment and contingencies
Bonus to be paid as a percentage of the participants base annual salary	10.00%
Agreement(s) \| Officer participants
Commitment and contingencies
Period of continued participation in health, disability and life insurance plans after involuntary termination	3 years
Agreement(s) \| Other participants
Commitment and contingencies
Period of continued participation in health, disability and life insurance plans after involuntary termination	2 years

Represents the annual vesting percentage of participants under the plan of the entity.

No definition available.

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- Definition

Represents the amount of bonus to be paid as a percentage of the participants' base annual salary.

+ References

No definition available.

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No definition available.

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- Definition

Represents the period of continued participation in health, disability and life insurance plans for the participants in the event of an involuntarily termination.

+ References

No definition available.

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Represents the period of graded vesting schedule in which the participants vest under the plan of the entity.

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No definition available.

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- Definition

Represents the amount of professional outplacement services that would be received by the participants in the event of an involuntarily termination.

+ References

No definition available.

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- References

No definition available.

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- Definition

Amount of labor-related expenses classified as other.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.4)
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Amount of stock repurchase plan authorized.

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- Definition

Amount remaining of a stock repurchase plan authorized.

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No definition available.

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- Definition

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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-Topic 210
-SubTopic 10
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Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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