STOCK BASED COMPENSATION (Unrecognized Compensation and the Expected Weighted-average Recognition Periods) (Details 3) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2017	Dec. 31, 2016
Employee stock option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost (in thousands)	$ 1,019	$ 0
Expected weighted-average recognition period for unrecognized compensation cost (in years)	2 years 5 months 9 days
Restricted stock/units awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost (in thousands)	$ 335	$ 113
Expected weighted-average recognition period for unrecognized compensation cost (in years)	1 year 3 months 18 days	11 months 1 day
Performance share incentives
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost (in thousands)	$ 818	$ 520
Expected weighted-average recognition period for unrecognized compensation cost (in years)	1 year 2 months 12 days	11 months 19 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 share-based awards, other than options, awarded to employees as compensation.

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