Antidilutive Securities, Reduction In Shares For Computation of Earnings Per Share

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Long-term Debt, Outstanding Principal Of Notes Converted Into Stock

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Long-term Debt, Outstanding Principal Of Notes Redeemed For Cash

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Repayments Of Long-term Debt, Including Equity Issuance

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Shares Issued During Period, Repayments Of Debt, Shares

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The amount of subsequent adjustments to additional paid in capital for convertible financial instruments where a component of equity and a component of debt are recognized.

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Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.

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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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Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Gross amount of debt extinguished.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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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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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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The cash inflow from a borrowing with the highest claim on the assets of the entity in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle, if longer).

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The cash outflow from the repayment of a long-term debt instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.

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Number of shares issued during the period as a result of the conversion of convertible securities.

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Debt - Narrative (Details) shares in Millions		1 Months Ended			3 Months Ended		9 Months Ended
Debt - Narrative (Details) shares in Millions	May 01, 2017 USD ($)	Apr. 30, 2017 USD ($) shares	Aug. 31, 2016 USD ($)	Feb. 29, 2016 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($) shares	Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($) shares	Mar. 31, 2017 USD ($)	Mar. 21, 2017 USD ($)
Debt Instrument [Line Items]
Loss on debt extinguishment					$ 0	$ 75,223,000	$ 65,000	$ 90,531,000
Repayments of convertible debt							$ 145,620,000	363,778,000
2% Notes
Debt Instrument [Line Items]
Stated interest rate (in hundredths)					2.00%		2.00%
Principal amount of notes converted into shares		$ 202,500,000
Principal amount of notes redeemed for cash		$ 5,100,000
Conversion rate (in shares per $1,000 note)		0.1438332
Loss on debt extinguishment		$ 70,000
Convertible Senior Notes
Debt Instrument [Line Items]
Stated interest rate (in hundredths)					5.00%		5.00%
Repayments of convertible debt	$ 145,000,000							195,500,000
Extinguishment of debt, amount								$ 188,500,000
Reduction in shares for computation of earnings per share \| shares								14.0
Convertible Senior Notes \| 2% Convertible Senior Notes
Debt Instrument [Line Items]
Shares issued during period upon conversion of convertible debt (in shares) \| shares		29.1
Repayments of convertible debt						230,700,000
Extinguishment of debt, amount						292,400,000
Repayments of debt, aggregate purchase price						$ 362,100,000
Shares issued for repayment of debt (in shares) \| shares						18.3
Reduction in shares for computation of earnings per share \| shares						42.1
Line of Credit \| Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity										$ 175,000,000
Revolving credit facility									$ 150,000,000
Senior Notes \| 5.75% Notes
Debt Instrument [Line Items]
Stated interest rate (in hundredths)			5.75%		5.75%		5.75%
Aggregate Principal Amount			$ 425,000,000
Net proceeds from issuance of debt			418,100,000
Other expenses associated with the issuance of notes			$ 1,200,000
9% Debentures
Debt Instrument [Line Items]
Stated interest rate (in hundredths)					9.00%		9.00%
Conversion rate (in shares per $1,000 note)							0.0740741
Loss on debt extinguishment				$ 8,300,000
Repayments of convertible debt				150,700,000
Extinguishment of debt, amount				$ 132,700,000
Reduction in shares for computation of earnings per share \| shares								9.8
Reacquisition of convertible junior subordinated debentures-equity component								$ 6,300,000