STOCKHOLDERS' EQUITY - Stock-based compensation (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Stock Based Compensation Expense
Stock-based compensation expense	$ 25.9	$ 6.5
Total estimated unrecognized compensation cost related to nonvested stock-based compensation arrangements	$ 37.2
Weighted average period recognized	1 year 2 months 12 days
Board of Directors
Stock Based Compensation Expense
Stock-based compensation expense	$ 0.9	0.8
Equity Classified Awards
Stock Based Compensation Expense
Stock-based compensation expense	25.8	6.5
Special awards expense
Stock Based Compensation Expense
Stock-based compensation expense	20.2
Performance stock unit expense
Stock Based Compensation Expense
Stock-based compensation expense	1.7	2.9
Restricted stock unit
Stock Based Compensation Expense
Stock-based compensation expense	3.0	$ 2.8
Liability classified awards
Stock Based Compensation Expense
Stock-based compensation expense	0.1
Restricted and performance stock unit expense
Stock Based Compensation Expense
Stock-based compensation expense	$ 0.1

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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