Earnings Per Common Share - Reconciliation of the Basic and Diluted EPS Denominators (Details) - shares shares in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Reconciliation of the basic and diluted EPS denominators
Basic weighted-average common shares	32,589	32,572	32,558	32,294
Dilutive effect of restricted common stock	156	424	274	501
Dilutive effect of Stock Warrants	163		173
Diluted weighted-average common shares	32,908	32,996	33,005	32,795

Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of call options and warrants using the treasury stock method.

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- Definition

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.

+ References

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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

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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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