| **Net Income Per Common Share and Equity per Common Share (Schedule Of Earnings Per Share) (Details) - shares shares in Thousands** | 12 Months Ended |
|-------------------------------------------------------------------------------------------------------------------------------------|-----------------|
||
| **Net Income Per Common Share and Equity per Commn Share [Abstract]**                                                               |            |   |   |
| Average common shares outstanding during the period for basic computation                                                           | 177,904         | 177,612 | 177,273 |
| Dilutive effect of employee stock-based compensation                                                                                | 495             | 563 | 573 |
| Average common shares outstanding during the period for diluted computation                                                         | 178,399         | 178,175 | 177,846 |

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| - References
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
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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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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
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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