Stock-Based Compensation (Schedule of Activity for Stock Options with Market Condition) (Details) - Performance Shares shares in Thousands	6 Months Ended
Jun. 30, 2018 shares
Unvested
Beginning balance, shares	707
Vested, shares	(31)
Canceled. shares	(428)
Ending balance, shares	248
Vested
Beginning balance, shares	83
Vested, shares	31
Exercised, shares	(9)
Canceled, shares	(10)
Ending balance, shares	95
Total
Beginning balance, shares	790
Canceled, shares	(438)
Ending balance, shares	343

Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested And Canceled, Number of Shares

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Canceled, Number

+ References

No definition available.

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- Definition

Number of options outstanding, including both vested and non-vested options.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

+ References

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Number of non-vested options outstanding.

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Number of non-vested options forfeited.

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Number of options vested.

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- Definition

Number of share options (or share units) exercised during the current period.

+ References

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