Earnings per Common Share - Calculation of Weighted-Average Shares Excluded from Diluted EPS (Details) - Stock appreciation rights and stock awards - shares shares in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Weighted-average stock appreciation rights and stock awards excluded from diluted EPS due to the anti-dilutive effect due to net loss	0	1,569	0	1,168
Weighted-average stock appreciation rights and stock awards excluded from diluted EPS due to the anti-dilutive effect calculated using the treasury stock method	0	0	774	827
Weighted-average stock appreciation rights and stock awards excluded from diluted EPS due to the anti-dilutive effect	0	1,569	774	1,995

Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount, Treasury Stock Method

No definition available.

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- Definition

Antidilutive Securities Excluded from Computation of Earnings Per Share due to Net Loss, Amount

+ References

No definition available.

+ Details

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-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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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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