Net Income Per Share (Reconciliation Between Basic And Diluted Weighted Average Shares Outstanding) (Details) - shares shares in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Basic weighted average shares outstanding	57,758	66,224	59,354	67,117
Diluted weighted average shares outstanding	58,387	66,789	60,044	67,771
Employee Stock Option [Member]
Incremental Weighted Average Shares Attributable to Dilutive Effect [Abstract]
Incremental Common Shares Attributable to Share-based Payment Arrangements	5	0	3	0
Restricted Stock Units (RSUs) [Member]
Incremental Weighted Average Shares Attributable to Dilutive Effect [Abstract]
Incremental Common Shares Attributable to Share-based Payment Arrangements	624	565	687	654

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.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
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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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