v2.4.0.6
Segment Reporting (Details) (USD $)
In Thousands, unless otherwise specified
 3 Months Ended 12 Months Ended
Dec. 31, 2012
Dec. 31, 2012
Dec. 31, 2011
Dec. 31, 2010
Segment Reporting        
Percentage of physical occupancy   95.00%    
Anniversary of completion of development or redevelopment   1 year    
Net income   $ 423,562 $ 441,370 $ 174,079
Indirect operating expenses, net of corporate income   31,911 30,550 30,246
Investments and investment management expense   6,071 5,126 3,824
Expensed acquisition, development and other pursuit costs   11,350 2,967 2,741
Interest expense, net   136,920 167,814 169,997
(Gain) loss on extinguishment of debt, net   1,179 1,940  
General and administrative expense   34,101 29,371 26,846
Equity in income of unconsolidated entities   (20,914) (5,120) (762)
Depreciation expense   256,026 239,060 220,563
Casualty and impairment loss 1,449 1,449 14,052  
Gain on sale of real estate assets   (146,591) (294,806) (74,074)
Income from discontinued operations   (12,495) (7,880) (7,950)
Gain on acquisition of unconsolidated real estate entity   (14,194)    
Net operating income   $ 708,375 $ 624,444 $ 545,510