Calculation Of Net Income Per Share (Weighted-Average Shares Used In Calculation Of Basic And Diluted EPS) (Details) - shares shares in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Earnings Per Share [Abstract]
Weighted-average number of common shares outstanding	115,058	118,513	113,452
Conversion spread related to Convertible Debentures	0	0	8,589
Unvested restricted stock units	240	455	620
Shares used to compute diluted net income per share	115,298	118,968	122,661

No definition available.

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Number of additional shares included in diluted EPS for potentially dilutive effect of nonvested equity-based payment award containing forfeitable rights to dividends or dividend equivalents, whether paid or unpaid.

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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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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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- Definition

Additional Shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of convertible debt securities using the treasury stock method.

+ References

No definition available.

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