STOCK-BASED COMPENSATION - Restricted Stock and Restricted Stock Units Additional Information (Details) $ in Thousands	3 Months Ended
Mar. 31, 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	$ 8,088
Weighted average period for recognition of unrecognized compensation expense (in years)	1 year 2 months 15 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	$ 30,341
Weighted average period for recognition of unrecognized compensation expense (in years)	2 years 4 months 14 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	$ 15,403
Weighted average period for recognition of unrecognized compensation expense (in years)	2 years 5 months 26 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	$ 457
Weighted average period for recognition of unrecognized compensation expense (in years)	1 year 2 months 14 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	$ 716
Weighted average period for recognition of unrecognized compensation expense (in years)	1 year 7 months 16 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	$ 8,922
Weighted average period for recognition of unrecognized compensation expense (in years)	1 year 1 month 19 days
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

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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-SubTopic 10
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