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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

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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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STOCKHOLDERS' EQUITY - Stock-based compensation (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Stock Based Compensation Expense
Stock-based compensation expense	$ 7.8	$ 19.4	$ 33.7	$ 25.9
Total estimated unrecognized compensation cost related to nonvested stock-based compensation arrangements	28.8		$ 28.8
Weighted average period recognized			1 year 1 month 6 days
Board of director stock award expense
Stock Based Compensation Expense
Stock-based compensation expense			$ 0.9	0.8
Equity Classified Awards
Stock Based Compensation Expense
Stock-based compensation expense	7.5	19.4	33.3	25.9
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	3.7	15.9	5.4	18.8
Restricted stock unit expense
Stock Based Compensation Expense
Stock-based compensation expense	3.8	$ 3.5	6.8	$ 6.3
Liability classified awards
Stock Based Compensation Expense
Stock-based compensation expense	0.3		0.4
Restricted and performance stock unit expense
Stock Based Compensation Expense
Stock-based compensation expense	$ 0.3		$ 0.4