Long-term Debt and Other Financing (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2015	Sep. 30, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Unamortized debt (discount) premium, net	$ (28.0)	$ (28.0)	$ (31.8)
Total long-term debt	2,386.3	2,386.3	2,452.5
Senior Secured Notes Due December 2018 [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 380.0	$ 380.0	$ 380.0
Debt Instrument, Interest Rate, Stated Percentage	8.75%	8.75%	8.75%
Exchangeable Senior Notes Due November 2019 [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 150.0	$ 150.0	$ 150.0
Debt Instrument, Interest Rate, Stated Percentage	5.00%	5.00%	5.00%
Debt Instrument, Interest Rate, Effective Percentage	10.80%	10.80%	10.80%
Senior Notes Due May 2020 [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 529.8	$ 529.8	$ 529.8
Debt Instrument, Interest Rate, Stated Percentage	7.625%	7.625%	7.625%
Senior Notes Due October 2021 [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 415.0	$ 415.0	$ 430.0
Debt Instrument, Repurchased Face Amount	$ 15.0	$ 15.0
Debt Instrument, Interest Rate, Stated Percentage	7.625%	7.625%	7.625%
Gain (Loss) on Repurchase of Debt Instrument	$ 4.3	$ 4.7
Senior Notes Due April 2022 [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 290.2	$ 290.2	$ 290.2
Debt Instrument, Interest Rate, Stated Percentage	8.375%	8.375%	8.375%
Industrial Revenue Bonds [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 99.3	$ 99.3	$ 99.3
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Credit Facility	$ 550.0	$ 550.0	$ 605.0

Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond one year or the normal operating cycle, if longer.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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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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Face (par) amount of the original debt instrument that was repurchased.

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The amount of debt discount (net of debt premium) that was originally recognized at the issuance of the instrument that has yet to be amortized.

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Amount of gain (loss) from the difference between the repurchase price of a debt instrument initially issued by the entity and the net carrying amount of the debt at the time of its repurchase.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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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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