COMMITMENTS AND CONTINGENCIES (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Schedule of Equity Method Investments [Line Items]
Accrued probable future environmental expenditures	$ 131.6		$ 131.6		$ 124.5
Expense related to environmental activities	18.8	$ 9.4	23.8	$ 22.4
Insurance recoveries	0.1		8.3	$ 4.5
Calvert City
Schedule of Equity Method Investments [Line Items]
Accrued probable future environmental expenditures	$ 120.9		$ 120.9

Total costs accrued as of the balance sheet date for environmental loss contingencies.

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