SHARE-BASED COMPENSATION - Narrative (Details) - USD ($) shares in Millions, $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	$ 2.3	$ 25.7
Stock option expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost, period of recognition	6 years
Restricted stock unit expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	$ 0.6	0.0
Unrecognized compensation cost	$ 8.6
Unrecognized compensation cost, period of recognition	4 years
Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	$ 1.7	25.7
Unrecognized compensation cost	$ 7.6
Tender offer \| Common stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense		$ 25.1
2020 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for issuance (in shares)	30.0

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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