v2.4.0.6

Acquisitions of Real Estate Property (Details 8) (USD $) In Thousands, except Share data, unless otherwise specified | 12 Months Ended
--- | ---
Dec. 31, 2011 | Dec. 31, 2010
The effect of material acquisitions on net income and earnings per share |  |
Revenues | $ 2,256,319 | $ 2,178,897
Income from continuing operations attributable to common stockholders | $ 583,446 | $ 321,637
Basic: |  |
Income from continuing operations attributable to common stockholders (in dollars per share) | $ 2.03 | $ 1.14
Diluted: |  |
Income from continuing operations attributable to common stockholders (in dollars per share) | $ 2.02 | $ 1.14
Weighted average shares used in computing earnings per common share: |  |
Basic (in shares) | 286,856 | 281,333
Diluted (in shares) | 289,193 | 282,382

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