LOSS PER SHARE - Narrative (Details) - shares shares in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Stock Compensation Plan
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Excluded from computation of diluted earnings per share, effect anti-dilutive (in shares)	3,154	5,106	3,763
Stock options, Time-based RSUs, Performance-based RSUs
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Excluded from computation of diluted earnings per share, effect anti-dilutive (in shares)	9,551	2,598	4,185

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-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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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration