STOCK-BASED COMPENSATION EXPENSE - Unrecognized Compensation Expense (Details) $ in Thousands	12 Months Ended
Dec. 31, 2021 USD ($)
Unrecognized compensation expense
Total unrecognized compensation expense at December 31, 2021	$ 325,163
Share-based Payment Arrangement, Option
Unrecognized compensation expense
Options	$ 930
Remaining weighted-average recognition period (years)	1 year 10 days
Market Based RSUs
Unrecognized compensation expense
Market Based RSUs and RSUs	$ 166,181
Remaining weighted-average recognition period (years)	1 year 6 months
RSUs
Unrecognized compensation expense
Market Based RSUs and RSUs	$ 158,052
Remaining weighted-average recognition period (years)	1 year 11 months 26 days

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=120381028&loc=d3e5070-113901

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