DEBT (Details 1) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015	Oct. 05, 2015
Debt Instrument [Line Items]
Notes payable	$ 3,674.5	$ 3,879.9
Transfers Accounted for as Secured Borrowings, Associated Liabilities, Carrying Amount	210.0	0.0
Capital Lease Obligations	3.9	4.6
Deferred Debt Issuance Costs and Unamortized Fair Value Premium	(28.5)	(32.7)
Interest Rates Swaps Classified in Debt	(28.4)	1.6
Debt, Long-term and Short-term, Combined Amount	3,617.6	3,848.8
Current installments of long-term debt	80.5	205.0
Total long-term debt	3,537.1	3,643.8
Senior Term Loan Facility
Debt Instrument [Line Items]
Notes payable	$ 1,282.5	$ 1,350.0
Interest rate	2.77%	2.17%
Sumitomo Credit Facility
Debt Instrument [Line Items]
Notes payable	$ 590.0	$ 800.0
Interest rate	2.27%	1.77%
Variable-Rate Recovery Zone Bonds
Debt Instrument [Line Items]
Notes payable	$ 103.0	$ 103.0
Interest rate	2.47%	1.40%
Variable -Rate Go Zone Bonds
Debt Instrument [Line Items]
Notes payable	$ 50.0	$ 50.0
Interest rate	2.47%	1.40%
Industrial Development and Environmental Improvement Obligations
Debt Instrument [Line Items]
Notes payable	$ 2.9	$ 2.9
Interest rate	0.25%	0.27%
2023 Notes
Debt Instrument [Line Items]
Notes payable	$ 720.0	$ 720.0
Interest rate	9.75%	9.75%	9.75%
2025 Notes
Debt Instrument [Line Items]
Notes payable	$ 500.0	$ 500.0
Interest rate	10.00%	10.00%	10.00%
2022 Notes
Debt Instrument [Line Items]
Notes payable	$ 200.0	$ 200.0
Interest rate	5.50%	5.50%
Notes payable due 2016
Debt Instrument [Line Items]
Notes payable	$ 0.0	$ 125.0
Interest rate	6.75%	6.75%
SunBelt Notes
Debt Instrument [Line Items]
Notes payable	$ 12.2	$ 24.4
Interest rate	7.23%	7.23%

Deferred Debt Issuance Costs and Unamortized Fair Value Premium Classified in Debt.

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Interest Rates Swaps Classified in Debt

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Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Represents the aggregate of total long-term debt, including current maturities and short-term debt.

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Amount of long-term debt, after unamortized discount or premium, scheduled to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Carrying amount of long-term debt, net of unamortized discount or premium, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities). Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

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Carrying amount of liabilities associated with financial assets accounted for as secured borrowings recognized in the transferor's statement of financial position at the end of each period presented.

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