Net Income Per Common Share (Details)	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Net Income Per Common Share
Weighted average shares used for the basic net income per share computation	225,346,407	207,003,950
Incremental shares from share-based compensation	162,425	3,391
Weighted average shares used for diluted net income per share computation	225,825,854	207,324,363
Unvested Shares
Net Income Per Common Share
Unvested shares from share-based compensation that were anti-dilutive	111,338	194,933
Convertible Partnership Units
Net Income Per Common Share
Weighted average partnership common units convertible to common shares that were dilutive	317,022	317,022
Unvested shares from share-based compensation that were anti-dilutive	440,546	534,546

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of shares issued in connection with business acquisition.

+ References

No definition available.

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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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.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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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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