Net Income (Loss) per Common Share (Details) - shares	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Employee Stock Option
Securities Included and Excluded from the Computation of Earnings Per Share
Weighted average number of shares included in computation of diluted earnings per share (in shares)	600,000	200,000	600,000	100,000
Weighted average shares excluded from computation of diluted earnings per share (in shares)	0	300,000	0	700,000
Restricted Stock
Securities Included and Excluded from the Computation of Earnings Per Share
Weighted average number of shares included in computation of diluted earnings per share (in shares)	100,000	200,000	200,000	200,000

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

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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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 28A
-URI http://asc.fasb.org/extlink&oid=109260490&loc=d3e1500-109256

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-Name Accounting Standards Codification
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