Number of shares related to shares acquired from exercise of call options.

No definition available.

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- Definition

Number of shares related to stock issued as a result of the exercise of warrants.

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No definition available.

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- Definition

Price per share of common stock for call options purchased.

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No definition available.

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- Definition

Period of specified consecutive trading days within which counterparties have the right to exercise warrants, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

The effective conversion price per share.

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No definition available.

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- Definition

Represents the face amount of senior notes used for effective conversion price.

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No definition available.

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- Definition

Represents the value of shares acquired upon exercise of call options.

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No definition available.

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- Definition

Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.

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Exercise price per share or per unit of warrants or rights outstanding.

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- Definition

The number of shares issued in exchange for the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or payments in the period.

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The price per share of the conversion feature embedded in the debt instrument.

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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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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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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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Amount of the cost of borrowed funds accounted for as interest expense for debt.

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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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Long-Term Debt (Details 7) (USD $)	1 Months Ended	12 Months Ended
Long-Term Debt (Details 7) (USD $)	Jun. 30, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jun. 30, 2009
Long-Term Debt
Amortization of debt discount		$ 12,380,000	$ 23,407,000	$ 20,523,000
Value of shares acquired upon exercise of call options		89,407,000
4.25% convertible senior notes due June 2014
Long-Term Debt
Principle amount of senior notes					355,000,000
Interest rate (as a percent)		4.25%	4.25%		4.25%
Conversion rate of debt instrument (Shares per USD)	0.0435084
Conversion price per common stock shares (in dollars per share)	$ 22.98
Repayment of long term debt	370,000,000
Number of shares of common stock issued upon redemption of debt	6,800,000
Amount of unamortized discount of notes			11,300,000		97,900,000
Recognized interest expense related to the contractual interest coupon		6,900,000	15,100,000	15,100,000
Amortization of debt discount		11,300,000	23,000,000	20,500,000
Effective interest rate (as a percent)					11.67%
Price per share of common stock for call options purchased (in dollars per share)	$ 22.98
Warrant exercise price (in dollars per share)		$ 32.19
Effective conversion price (in dollars per share)		$ 32.19
Debt instrument face amount for effective conversion price		325,000,000
Number of shares acquired upon exercise of call options	6,500,000
Value of shares acquired upon exercise of call options	$ 89,400,000
Trading days within which counterparties have the right to exercise warrants		80 days
Common shares issued pursuant to warrants exercised		1,600,000