Earnings per Share Earnings per Share (Weighted Average Shares Outstanding) (Details) - shares shares in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Schedule of Basic And Diluted Weighted Average Common Shares Outstanding [Line Items]
Weighted-average common shares outstanding (in shares)	218,042	214,683	216,140	214,658
Diluted weighted-average common shares outstanding (in shares)	218,847	215,325	216,912	215,218
Restricted stock awards
Schedule of Basic And Diluted Weighted Average Common Shares Outstanding [Line Items]
Assumed conversion of dilutive securities (in shares)	110	127	56	96
Performance-based restricted stock awards
Schedule of Basic And Diluted Weighted Average Common Shares Outstanding [Line Items]
Assumed conversion of dilutive securities (in shares)	695	515	716	464

[Line Items] for Schedule of Basic And Diluted Weighted Average Common Shares Outstanding [Table]

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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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-Publisher FASB
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-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.

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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.

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