Earnings Per Share (Details) - shares	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Reconciliation of number of shares used in calculation of basic and diluted earnings per share
Weighted average number of common shares outstanding	84,378,960	85,952,347
Effect of non-participatory equity compensation (in shares)	40,000	40,000
Weighted average number of common shares outstanding, including effect of dilutive securities	84,418,960	85,992,347

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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 28A
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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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No definition available.

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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.

+ References

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-Topic 260
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