Earnings (Loss) Per Share - Basic and Diluted Earnings per Share (Details) - shares shares in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Class of Stock [Line Items]
Weighted average common shares outstanding - Basic (in shares)	58,319	57,602	57,820	57,709
Assumed conversions:
Weighted average common shares outstanding - Diluted (in shares)	58,319	57,602	57,820	57,709
Stock Options
Assumed conversions:
Incremental common shares from stock options and restricted stock units (in shares)	0	0	0	0
Restricted Stock Units
Assumed conversions:
Incremental common shares from stock options and restricted stock units (in shares)	0	0	0	0

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.

No definition available.

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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

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

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- Definition

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.

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