STOCK-BASED COMPENSATION - Summary of All Share Awards Outstanding Under All Plans (Details) - shares	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award
Total share awards outstanding (in shares)	4,011,697	1,493,224
Time-based stock options
Share-based Compensation Arrangement by Share-based Payment Award
Options outstanding (in shares)	2,605,167	913,960
Time-based restricted stock awards
Share-based Compensation Arrangement by Share-based Payment Award
Non-option stock awards outstanding (in shares)	1,039,380	312,245
Performance-based restricted stock awards
Share-based Compensation Arrangement by Share-based Payment Award
Non-option stock awards outstanding (in shares)	0	101,384
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)	367,150	165,635

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

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.

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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