EARNINGS PER SHARE - Schedule of Antidilutive and Contingently Issuable Shares (Details) - shares shares in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based awards excluded from diluted EPS	4,611	2,830	4,343	2,662
Performance-based restricted stock awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Contingently issuable awards excluded from diluted EPS (in shares)	0	62	0	67
Performance-based restricted stock awards with a market condition
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Antidilutive awards excluded from diluted EPS (in shares)	294	0	0	0
Contingently issuable awards excluded from diluted EPS (in shares)	0	387	308	416
Convertible shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based awards excluded from diluted EPS			2,900
Time-based options and restricted stock awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Antidilutive awards excluded from diluted EPS (in shares)	3,076	2,381	3,022	2,179
Performance-based restricted stock awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Antidilutive awards excluded from diluted EPS (in shares)	1,241	0	1,013	0

Contingently Issuable Securities Excluded from Computation of Earnings Per Share, Amount

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Securities Excluded from Computation of Diluted Earnings Per Share, Amount

+ References

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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