Basis of Presentation (Reconciliation of Weighted Average Shares Table) (Details) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Numerator
Net income (loss) - basic	$ (25,674)	$ 39,578
Interest on convertible senior notes	0	501
Net income (loss) - diluted	$ (25,674)	$ 40,079
Denominator
Weighted average common shares outstanding - basic	451,720	392,742
Restricted stock and performance-based equity awards	0	5,169
Convertible senior notes	0	53,632
Weighted average common shares outstanding - diluted	451,720	451,543

The reconciliation of the numerator in the diluted EPS calculation.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of convertible debt securities using the if-converted method.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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The after-tax amount of interest recognized in the period associated with any convertible debt.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities, and addition from assumption of issuance of common shares for dilutive potential common shares; of income (loss) available to common shareholders.

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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