STOCK-BASED COMPENSATION - Restricted Stock and Restricted Stock Units Additional Information (Details) $ in Thousands	6 Months Ended
Jun. 30, 2016 USD ($)
Acquisition-related Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	3 years
Service Period \| Equity Classified Award \| Equity-Settled Award \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	$ 6,767
Weighted average period for recognition of unrecognized compensation expense (in years)	1 year 28 days
Service Period \| Equity Classified Award \| Equity-Settled Award \| Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	$ 28,791
Weighted average period for recognition of unrecognized compensation expense (in years)	2 years 3 months 10 days
Service Period \| Liability Classified Award \| Cash-Settled Award \| Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	$ 11,145
Weighted average period for recognition of unrecognized compensation expense (in years)	2 years 4 months 20 days
Performance Target \| Equity Classified Award \| Equity-Settled Award \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	$ 277
Weighted average period for recognition of unrecognized compensation expense (in years)	1 year 2 months 10 days
Performance Target \| Equity Classified Award \| Equity-Settled Award \| Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	$ 634
Weighted average period for recognition of unrecognized compensation expense (in years)	1 year 5 months 24 days
Performance Target \| Liability Classified Award \| Equity-Settled Award \| Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	$ 6,687
Weighted average period for recognition of unrecognized compensation expense (in years)	1 year
Year One \| Acquisition-related Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	33.30%
Year Two \| Acquisition-related Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	33.30%
Year Three \| Acquisition-related Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	33.30%

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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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Percentage of vesting of share-based compensation awards.

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