Earnings per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Earnings Per Share [Abstract]
Net income	$ (14,742)	$ 9,272	$ (2,958)	$ 19,567
Basic earnings per share:
Income available to common stockholders	$ (14,742)	9,272	$ (2,958)	19,567
Weighted average shares outstanding - basic (in shares)	111,346,897		111,346,897
Basic earning per share (in usd per share)	$ (0.13)		$ (0.03)
Diluted earnings per share:
Income available to common stockholders	$ (14,742)	$ 9,272	$ (2,958)	$ 19,567
Weighted average shares outstanding - diluted (in shares)	111,346,897		111,346,897
Diluted earnings per share (in usd per share)	$ (0.13)		$ (0.03)

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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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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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; of income (loss) available to common shareholders.

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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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