Consolidated Statements Of Operations (USD $)
In Thousands, except Per Share data, unless otherwise specified
 12 Months Ended
Dec. 31, 2011
Dec. 31, 2010
Dec. 31, 2009
REVENUES      
Base rents $ 600,163 $ 602,357 $ 611,061
Escalations and recoveries from tenants 94,047 101,699 103,057
Construction services 12,058 62,997 21,910
Real estate services 5,199 7,874 9,359
Other income 12,812 12,553 13,538
Total revenues 724,279 787,480 758,925
EXPENSES      
Real estate taxes 87,473 93,535 93,322
Utilities 73,274 74,077 70,927
Operating services 117,645 114,452 110,169
Direct construction costs 11,458 60,255 20,323
General and administrative 35,541 35,003 39,779
Depreciation and amortization 193,587 191,168 200,732
Impairment charge on rental property   9,521  
Total expenses 518,978 578,011 535,252
Operating income 205,301 209,469 223,673
OTHER (EXPENSE) INCOME      
Interest expense (125,975) (149,329) (140,068)
Interest and other investment income 39 86 570
Equity in earnings (loss) of unconsolidated joint ventures 2,022 2,276 (5,560)
Loss from early extinguishment of debt   (3,752)  
Gain on reduction of other obligations     1,693
Total other (expense) income (123,914) (150,719) (143,365)
Income from continuing operations 81,387 58,750 80,308
Discontinued operations:      
Income (loss) from discontinued operations   242 (17)
Impairment charge on rental property     (16,563)
Realized gains (losses) and unrealized losses on disposition of rental property, net   4,447  
Total discontinued operations, net   4,689 (16,580)
Net income 81,387 63,439 63,728
Noncontrolling interest in consolidated joint ventures 402 262 943
Noncontrolling interest in Operating Partnership (10,369) (8,133) (12,550)
Noncontrolling interest in discontinued operations   (668) 2,447
Preferred stock dividends (1,736) (2,000) (2,000)
Net income available to common shareholders $ 69,684 $ 52,900 $ 52,568
Basic earnings per common share:      
Income from continuing operations $ 0.81 $ 0.62 $ 0.90
Discontinued operations   $ 0.05 $ (0.19)
Net income available to common shareholders $ 0.81 $ 0.67 $ 0.71
Diluted earnings per common share:      
Income from continuing operations $ 0.81 $ 0.62 $ 0.90
Discontinued operations   $ 0.05 $ (0.19)
Net income available to common shareholders $ 0.81 $ 0.67 $ 0.71
Basic weighted average shares outstanding 86,047 79,224 74,318
Diluted weighted average shares outstanding 98,962 92,477 88,389