SHARE-BASED COMPENSATION - Schedule of Unrecognized Compensation Expense (Details) $ in Millions	3 Months Ended
Mar. 31, 2020 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized Compensation Cost	$ 50.1
Weighted Average Remaining Period to be Recognized (Years)	2 years 6 months 14 days
Time-based stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost, Time-based stock options	$ 0.0
Weighted Average Remaining Period to be Recognized (Years)	3 months
Time-based restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost, Time-based and Performance-based restricted stock	$ 48.1
Weighted Average Remaining Period to be Recognized (Years)	2 years 7 months 20 days
Performance-based restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost, Time-based and Performance-based restricted stock	$ 2.0
Weighted Average Remaining Period to be Recognized (Years)	3 months
2020 Performance Shares \| Performance-based restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized Compensation Cost	$ 8.1
2018 Performance Shares \| Performance-based restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized Compensation Cost	25.1
2017 Performance Shares \| Performance-based restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost, Time-based and Performance-based restricted stock	13.8
Unrecognized Compensation Cost	$ 12.1

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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