Earnings Per Share - Diluted (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Diluted earnings per share
Net loss	$ (33,035)	$ (10,277)
Less: cumulative preferred stock dividends	4,832	0
Numerator	$ (37,867)	$ (10,277)
Weighted average common stock outstanding	78,198	65,692
Effect of dilutive securities	0	0
Denominator, Net, Diluted	78,198	65,692
Diluted earnings (loss) per share, Net	$ (0.48)	$ (0.16)

The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of contingently issuable shares. Contingently issuable shares are those shares that are issuable for little or no cash contingent on certain conditions being met.

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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 amount of preferred stock dividends that is an adjustment to net income apportioned to common stockholders.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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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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This element represents the weighted average total number of shares issued throughout the period including the first (beginning balance outstanding) and last (ending balance outstanding) day of the period before considering any reductions (for instance, shares held in treasury) to arrive at the weighted average number of shares outstanding. Weighted average relates to the portion of time within a reporting period that common shares have been issued and outstanding to the total time in that period. Such concept is used in determining the weighted average number of shares outstanding for purposes of calculating earnings per share (basic).

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