Earnings Per Share (Schedule Of Reconciliation Of Shares Outstanding For 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
Shares outstanding for basic earnings per share:
Shares outstanding for basic earnings per share (in shares)	86,756	87,537	87,029	87,884
Shares outstanding for diluted earnings per share:
Shares outstanding for basic earnings per share (in shares)	86,756	87,537	87,029	87,884
Dilutive effect of share-based payment awards (in shares)	1,697	1,719	1,658	1,851
Shares outstanding for diluted earnings per share (in shares)	88,453	89,256	88,687	89,735

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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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.

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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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