Long-term Debt and Other Financing (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Jun. 30, 2017	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Debt Instrument [Line Items]
Capital Lease Obligations		$ 25.2		$ 25.2
Unamortized debt discount/premium and debt issuance costs		(56.0)		(53.7)
Total debt		1,853.0		1,816.6
Current portion of long-term debt		168.5		0.0
Total long-term debt		1,684.5		1,816.6
Debt issuance costs		7.8	$ 0.0
Exchangeable notes exchange feature		19.7		21.3
Senior Secured Notes Due July 2023 [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross		$ 380.0		$ 380.0
Debt Instrument, Interest Rate, Effective Percentage		8.30%		8.30%
Debt Instrument, Interest Rate, Stated Percentage		7.50%		7.50%
Exchangeable Senior Notes Due November 2019 [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross		$ 150.0		$ 150.0
Debt Instrument, Interest Rate, Effective Percentage		10.80%		10.80%
Debt Instrument, Interest Rate, Stated Percentage		5.00%		5.00%
Debt Instrument, Convertible, Stock Price Trigger		$ 7.02
Debt Instrument, Convertible, Threshold Percentage of Stock Price Trigger		130.00%
Debt Instrument, Convertible, Threshold Trading Days		20
Debt Instrument, Convertible, Threshold Consecutive Trading Days		30 days
Exchangeable notes exchange feature		$ 19.7		$ 21.3
Debt Instrument, Convertible, If-converted Value in Excess of Principal		63.6
Senior Notes Due May 2020 [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross		$ 168.5		$ 529.8
Debt Instrument, Interest Rate, Stated Percentage		7.625%		7.625%
Debt Instrument, Redemption Price, Percentage		102.125%
Debt Instrument, Repurchased Face Amount		$ (361.3)
Gain (Loss) on Repurchase of Debt Instrument		$ (9.7)
Senior Notes Due May 2020 [Member] | Debt Instrument, Redemption, Period Two [Member]
Debt Instrument [Line Items]
Debt Instrument, Redemption Price, Percentage		101.271%
Senior Notes Due October 2021 [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross		$ 406.2		$ 406.2
Debt Instrument, Interest Rate, Stated Percentage		7.625%		7.625%
Senior Notes Due April 2022 [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross		$ 279.8		$ 279.8
Debt Instrument, Interest Rate, Stated Percentage		8.375%		8.375%
Senior Notes Due March 2027 [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross		$ 400.0		$ 0.0
Debt Instrument, Interest Rate, Stated Percentage		7.00%
Proceeds from Debt, Net of Issuance Costs		$ 394.0
Debt issuance costs		$ 7.5
Senior Notes Due March 2027 [Member] | Debt Instrument, Redemption, Period One [Member]
Debt Instrument [Line Items]
Debt Instrument, Redemption, Description		Before March 15, 2022, we may redeem the 2027 Notes at a price equal to par plus a make-whole premium and all accrued and unpaid interest to the date of redemption.
Debt Instrument, Redemption Period, End Date		Mar. 14, 2022
Senior Notes Due March 2027 [Member] | Debt Instrument, Redemption, Period Two [Member]
Debt Instrument [Line Items]
Debt Instrument, Redemption Price, Percentage		103.50%
Debt Instrument, Redemption Period, Start Date		Mar. 15, 2022
Debt Instrument, Redemption Period, End Date		Mar. 14, 2023
Senior Notes Due March 2027 [Member] | Debt Instrument, Redemption, Period Three [Member]
Debt Instrument [Line Items]
Debt Instrument, Redemption Price, Percentage		102.333%
Debt Instrument, Redemption Period, Start Date		Mar. 15, 2023
Debt Instrument, Redemption Period, End Date		Mar. 14, 2024
Senior Notes Due March 2027 [Member] | Debt Instrument, Redemption, Period Four [Member]
Debt Instrument [Line Items]
Debt Instrument, Redemption Price, Percentage		101.167%
Debt Instrument, Redemption Period, Start Date		Mar. 15, 2024
Debt Instrument, Redemption Period, End Date		Mar. 14, 2025
Senior Notes Due March 2027 [Member] | Debt Instrument, Redemption, Period Five [Member]
Debt Instrument [Line Items]
Debt Instrument, Redemption Price, Percentage		100.00%
Debt Instrument, Redemption Period, Start Date		Mar. 15, 2025
Debt Instrument, Redemption Period, End Date		Mar. 15, 2027
Industrial Revenue Bonds [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross		$ 99.3		99.3
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Credit Facility		$ 0.0		$ 0.0
Line of Credit Facility, Expiration Date		Mar. 31, 2019
Scenario, Forecast [Member] | Senior Notes Due May 2020 [Member]
Debt Instrument [Line Items]
Gain (Loss) on Repurchase of Debt Instrument	$ (3.4)