Fair Value Measurements, Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2017	Dec. 31, 2016
Cash Convertible Notes Hedges [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance at beginning of period	$ 48,361
Purchases of Level 3 instruments	0
Settlements of Level 3 instruments	0
Gains (Losses) included in Earnings	112,515
Balance at end of period	160,876
Cash Conversion Derivative [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance at beginning of period	(48,361)
Purchases of Level 3 instruments	0
Settlements of Level 3 instruments	0
Gains (Losses) included in Earnings	(112,515)
Balance at end of period	(160,876)
Recurring [Member] \| Cash Convertible Notes Hedges [Member] \| Level 3 [Member]
Assets [Abstract]
Fair Value	160,876	$ 48,361
Recurring [Member] \| Cash Conversion Derivative [Member] \| Level 3 [Member]
Liabilities [Abstract]
Fair Value	$ 160,876	$ 48,361

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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
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of increase (decrease) of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of settlement of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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