Long-Term Debt (Details 2) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	May 21, 2013
Long-term debt
Fair value of the liability component	$ 204,737
Accumulated accretion of discount	8,369
Net carrying amount (Long term debt)	213,106
Short term portion of long term debt	0
Convertible Senior Notes Due 2020
Long-term debt
Fair value of the liability component	154,737	154,700
Accumulated accretion of discount	8,369
Net carrying amount (Long term debt)	163,106
Senior Secured Notes Due 2018
Long-term debt
Net carrying amount (Long term debt)	$ 50,000

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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.

+ References

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

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- Definition

Amount of long-term debt, after unamortized discount or premium, scheduled to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

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+ Details

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- Definition

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.

+ References

No definition available.

+ Details

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