Contractual interest rate for funds borrowed, under the debt agreement.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

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Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 50

-Paragraph 3

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=34720828&loc=SL20225862-175312

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4B

-Subparagraph (a),(c)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624163-113959

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 55

-Paragraph 7

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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Fixed interest rate related to the interest rate derivative.

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Derivative Financial Instruments Fair Value on Consolidated Balance Sheets (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014 1.125% Call Option	Jun. 30, 2013 1.125% Call Option	Jun. 30, 2014 Non-current asset 1.125% Call Option	Dec. 31, 2013 Non-current asset 1.125% Call Option	Jun. 30, 2014 Non-current liabilities Embedded cash conversion option	Dec. 31, 2013 Non-current liabilities Embedded cash conversion option	Jun. 30, 2014 1.125% Notes
Derivative [Line Items]
Derivative assets			$ 250,160	$ 186,351
Derivative liabilities					$ 250,038	$ 186,239
Percentage of contractual interest rate on Call Option	1.125%	1.125%
Percentage of contractual interest rate on Notes							1.125%