Income Per Share (Summary Of Basic And Diluted Earnings Per Share) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Income Per Share [Abstract]
Net income available to common stockholders	$ 42,657	$ 39,211
Weighted average shares outstanding-basic	126,445,285	107,099,856
Stock options	70,877	205,830
Class C Units (2007 Grant)		16,358
Unvested incentive units	222,177	262,812
Weighted average shares/units outstanding-diluted	126,738,339	107,584,856
Basic	$ 0.34	$ 0.37
Diluted	$ 0.34	$ 0.36

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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+ Details

- Definition

The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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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.

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- 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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-Glossary Weighted-Average Number of Common Shares Outstanding

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+ Details