STOCK-BASED COMPENSATION - Restricted Stock Units - Unrecognized Compensation Cost (Details) - Restricted stock units $ in Thousands	12 Months Ended
Dec. 31, 2015 USD ($)
Unrecognized compensation cost
Unrecognized compensation cost	$ 7,188
Expected weighted-average recognition period for compensation cost	3 years 11 months 5 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=6415400&loc=d3e5070-113901

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Data Type:	xbrli:durationItemType
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Period Type:	duration