STOCK BASED COMPENSATION - Intrinsic Value of Stock Options and Additional Disclosures (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Additional disclosures
Compensation expense	$ 382	$ 315	$ 359
Stock options
Information related to the 2007 stock incentive plan and the 2003 plan
Intrinsic value of options exercised	1,306	244	55
Cash received from option exercises	1,556	294	$ 66
Tax benefit realized from option exercises	$ 164	31
Weighted average fair value of options granted (in dollars per share)			$ 3.78
Additional disclosures
Weighted-average period of expected recognition of the cost	1 year
Total unrecognized compensation cost related to nonvested stock options granted	$ 30
Compensation expense	91	180	$ 160
Performance units \| Executive officers
Additional disclosures
Compensation expense	$ 240	$ 79

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901

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Aggregate proceeds received by the entity during the annual period from exercises of stock or unit options and conversion of similar instruments granted under equity-based payment arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Unrecognized cost of unvested options awarded to employees as compensation.

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Disclosure of the aggregate tax benefit realized from the exercise of stock options and the conversion of similar instruments during the annual period.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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