Long-term Debt and Other Financing Long-term debt table (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Dec. 31, 2012
Debt Instrument [Line Items]
Debt Instrument, Unamortized Discount	$ (38.0)	$ (39.0)
Total debt	1,412.6	1,411.9
Current portion of long-term debt	0.7	0.7
Long-term debt	1,411.9	1,411.2
Senior Secured Notes Due December 2018 [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	350.0	350.0
Exchangeable Senior Notes Due November 2019 [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	150.0	150.0
Debt Instrument, Convertible, Effective Interest Rate	10.80%
Senior Notes Due May 2020 [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	550.0	550.0
Senior Notes Due April 2022 [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	300.0	300.0
Industrial Revenue Bonds [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 100.6	$ 100.9

Including current and noncurrent portions, aggregate carrying amount of long-term borrowings as of the balance sheet date before deducting unamortized discount or premiums (if any). May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer.

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The effective interest rate on the liability component of convertible debt instrument which may be settled in cash upon conversion, including partial cash settlement.

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

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. 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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