Including the current and noncurrent portions, carrying amount of debt identified as being convertible into another form of financial instrument (typically the entity's common stock) as of the balance sheet date, which originally required full repayment more than twelve months after issuance or greater than the normal operating cycle of the company.

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The number of equity instruments that the holder of the debt instrument would receive if the debt was converted to equity.

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Face (par) amount of debt instrument at time of issuance.

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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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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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Summary of Significant Accounting Policies - Schedule of Estimated Fair Value and Principal Amount of Outstanding Debt (Details) shares in Millions, instrument in Millions, $ in Millions	1 Months Ended	12 Months Ended
	Jan. 31, 2017 USD ($) shares	Dec. 31, 2016 USD ($) instrument	Dec. 31, 2015 USD ($)	Dec. 31, 2009
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value		$ 755.7	$ 735.2
Principal Amount		725.6	650.6
Convertible senior notes		240.0	0.0
Term Loan [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value		390.0	92.5
Principal Amount		390.0	92.5
7.125% Second-Priority Senior Secured Notes [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value		0.0	479.6
Principal Amount		$ 0.0	460.0
Debt instrument interest rate stated percentage		7.125%
2.25% Convertible Senior Notes (2 1/4% Notes) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value		$ 294.9	0.0
Principal Amount		$ 300.0	0.0
Debt instrument interest rate stated percentage		2.25%
4 1/16% Convertible Subordinated Debentures [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value		$ 70.8	149.5
Principal Amount		$ 35.6	84.6
Debt instrument interest rate stated percentage		4.0625%		4.0625%
Convertible debentures into shares of common stock (in shares) \| instrument		3.9
4 1/16% Convertible Subordinated Debentures [Member] \| Subsequent Event [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Convertible senior notes	$ 35.6
Convertible debentures into shares of common stock (in shares) \| shares	3.9
Delayed Draw Term Loan [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value		$ 0.0	13.0
Principal Amount		0.0	13.0
Other Debt [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value		0.0	0.6
Principal Amount		$ 0.0	$ 0.5