L. SHARE-BASED COMPENSATION - SHARE-BASED COMPENSATION EXPENSE 2 (Details) $ in Millions	12 Months Ended
Dec. 31, 2016 USD ($)
Compensation cost on unvested options not yet recognized	$ 0.8
Compensation cost unrecognized weighted average period	9 months 18 days
Restricted stock units
Compensation cost on unvested options not yet recognized	$ 6.3
Compensation cost unrecognized weighted average period	2 years 10 months 28 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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Period Type:	duration