Net Income Per Share (Reconciliation Between Basic And Diluted Weighted Average Shares Outstanding) (Details) - shares shares in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Basic weighted average shares outstanding	56,875	63,683	58,519	65,960
Diluted weighted average shares outstanding	57,779	64,447	59,281	66,651
Employee Stock Option [Member]
Incremental Weighted Average Shares Attributable to Dilutive Effect [Abstract]
Incremental Common Shares Attributable to Share-based Payment Arrangements	31	4	12	1
Restricted Stock Units (RSUs) [Member]
Incremental Weighted Average Shares Attributable to Dilutive Effect [Abstract]
Incremental Common Shares Attributable to Share-based Payment Arrangements	873	760	750	690

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
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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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