STOCK-BASED COMPENSATION - Summary of All Share Awards Outstanding Under All Plans (Details) - shares	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award
Total share awards outstanding (in shares)	3,892,477	3,468,029
Time-based stock options
Share-based Compensation Arrangement by Share-based Payment Award
Options outstanding (in shares)	1,897,109	2,173,488
Time-based restricted stock awards
Share-based Compensation Arrangement by Share-based Payment Award
Non-option stock awards outstanding (in shares)	1,040,431	817,696
Performance-based restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award
Non-option stock awards outstanding (in shares)	954,937	277,817
Performance-based restricted stock awards with a market condition
Share-based Compensation Arrangement by Share-based Payment Award
Non-option stock awards outstanding (in shares)	0	199,028

Share based Compensation Arrangement by Share based Payment Award Outstanding Number

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)-(ii)
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- Definition

Number of options outstanding, including both vested and non-vested options.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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