STOCK-BASED COMPENSATION PLANS - Summary of Total Unrecognized Compensation Costs Related to Unvested Stock-Based Compensation (Details) $ in Thousands	12 Months Ended
Dec. 31, 2017 USD ($)
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Unrecognized compensation	$ 3,213
Weighted-average remaining recognition period (in years)	1 year 11 months 1 day
Stock options
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Unrecognized compensation	$ 241
Weighted-average remaining recognition period (in years)	2 years 6 months 3 days
Restricted stock
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Unrecognized compensation	$ 2,972
Weighted-average remaining recognition period (in years)	1 year 10 months 13 days

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

Unrecognized cost of unvested options awarded to employees as compensation.

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- Definition

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+ References

No definition available.

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