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DEBT (Details 1) - USD ($) $ in Millions	12 Months Ended
DEBT (Details 1) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Mar. 31, 2021
Debt Instrument [Line Items]
Notes payable	$ 2,601.0	$ 2,802.1
Receivables Financing Agreement (See Note 6)	300.0	300.0
Finance lease obligations	1.9	3.0
Deferred debt issuance costs	(20.1)	(22.5)
Unamortized bond original issue discount	0.2	0.3
Total debt	2,580.7	2,779.3
Amounts due within one year	9.7	201.1
Total long-term debt	2,571.0	2,578.2
Repayments	(616.1)	(1,643.1)	$ (1,307.2)
Loss on Extinguishment of Debt	0.0	152.2	$ 20.4
Proceeds from Issuance of Long-term Debt	415.0	540.0
Long-term debt (repayments) borrowings, net	(201.1)	(1,103.1)
$350.0 million Senior Term Loan
Debt Instrument [Line Items]
Notes payable	$ 350.0	$ 350.0
Interest rate	5.923%	1.60%
Variable-Rate Recovery Zone Bonds
Debt Instrument [Line Items]
Notes payable	$ 103.0	$ 103.0
Interest rate	5.198%	1.10%
Variable-Rate Go Zone Bonds
Debt Instrument [Line Items]
Notes payable	$ 50.0	$ 50.0
Interest rate	5.198%	1.10%
Industrial Development and Environmental Improvement Obligations
Debt Instrument [Line Items]
Notes payable	$ 2.9	$ 2.9
Interest rate	4.55%	0.17%
2025 Notes 9.50%
Debt Instrument [Line Items]
Notes payable	$ 108.6	$ 108.6
Interest rate	9.50%	9.50%
Repayments	$ 0.0	$ (391.4)
Loss on Extinguishment of Debt		103.8
2029 Notes
Debt Instrument [Line Items]
Notes payable	$ 669.3	$ 669.3
Interest rate	5.625%	5.625%
2022 Notes
Debt Instrument [Line Items]
Notes payable	$ 0.0	$ 200.0
Interest rate	5.50%	5.50%
Repayments	$ (200.0)	$ 0.0
Loss on Extinguishment of Debt		0.0
2027 Notes
Debt Instrument [Line Items]
Notes payable	$ 500.0	$ 500.0
Interest rate	5.125%	5.125%
2030 Notes
Debt Instrument [Line Items]
Notes payable	$ 515.3	$ 515.3
Interest rate	5.00%	5.00%
$1,200 million Senior Revolving Credit Facility
Debt Instrument [Line Items]
Repayments	$ (320.0)	$ 0.0
Loss on Extinguishment of Debt		0.0
Proceeds from Issuance of Long-term Debt	320.0	0.0
Senior Term Loans
Debt Instrument [Line Items]
Repayments	0.0	(465.0)
Loss on Extinguishment of Debt		2.0
Proceeds from Issuance of Long-term Debt	0.0	315.0
Receivables Financing Agreement
Debt Instrument [Line Items]
Receivables Financing Agreement (See Note 6)	300.0
Repayments	(95.0)	(50.0)
Loss on Extinguishment of Debt		0.0
Proceeds from Issuance of Long-term Debt	95.0	225.0
10.00% Senior Notes Due 2025
Debt Instrument [Line Items]
Interest rate				10.00%
Repayments	0.0	(500.0)
Loss on Extinguishment of Debt		30.9
9.75% Senior Notes Due 2023
Debt Instrument [Line Items]
Repayments	0.0	(120.0)
Loss on Extinguishment of Debt		3.7
5.625% Senior Notes Due 2029
Debt Instrument [Line Items]
Repayments	0.0	(80.7)
Loss on Extinguishment of Debt		9.0
5.00% Senior Notes Due 2030
Debt Instrument [Line Items]
Repayments	0.0	(34.7)
Loss on Extinguishment of Debt		2.8
Finance Leases
Debt Instrument [Line Items]
Repayments	$ (1.1)	(1.3)
Loss on Extinguishment of Debt		$ 0.0