Carrying value as of the balance sheet date of long-term debt (with maturities initially due after one year or beyond the operating cycle if longer) identified as Convertible Notes Payable, excluding current portion. Convertible Notes Payable is a written promise to pay a note which can be exchanged for a specified amount of another, related security, at the option of the issuer and the holder.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of a written promise to pay a note, initially due after one year or beyond the operating cycle if longer, which can be exchanged for a specified amount of one or more securities (typically common stock), at the option of the issuer or the holder.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Carrying value as of the balance sheet date of the portion of long-term debt due within one year or the operating cycle if longer identified as Convertible Notes Payable. Convertible Notes Payable is a written promise to pay a note which can be exchanged for a specified amount of another, related security, at the option of the issuer and the holder.

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

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-Publisher FASB
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No definition available.

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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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Convertible Notes (Schedule of Notes) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Aug. 16, 2013	Jul. 10, 2009	Jun. 29, 2009
Debt Instrument [Line Items]
Total convertible notes	$ 120,901	$ 115,089
Less current portion	0	0
Total long-term convertible notes	120,901	115,089
Convertible notes \| 1.125% Convertible Senior Notes due 2018
Debt Instrument [Line Items]
Face Value	138,000	138,000	$ 138,000
Unamortized discount	$ (17,099)	$ (22,911)
Convertible notes \| 5% Convertible Senior Notes due 2014
Debt Instrument [Line Items]
Face Value				$ 22,500	$ 150,000