Condensed Quarterly Financial Information (Tables)
 12 Months Ended
Dec. 31, 2011
Condensed Quarterly Financial Information [Abstract]  
Condensed Quarterly Financial Information
Quarter Ended 2011
December 31
September 30
June 30
March 31
Total revenues
$179,687
$177,155
$181,107
$186,330
Operating and other expenses
69,844
62,661
69,921
75,966
Direct construction costs
2,802
2,290
2,784
3,582
General and administrative
9,003
8,683
9,226
8,629
Depreciation and amortization
48,673
48,498
48,268
48,148
Impairment charge on rental property
--
--
--
--
Total expenses
130,322
122,132
130,199
136,325
Operating Income
49,365
55,023
50,908
50,005
Interest expense
(31,784)
(31,489)
(31,363)
(31,339)
Interest and other investment income
9
10
10
10
Equity in earnings (loss) of unconsolidated
        
joint ventures
848
539
736
(101)
Loss from early extinguishment of debt
--
--
--
--
Gain on reduction of other obligations
--
--
--
--
Total other (expense) income
(30,927)
(30,940)
(30,617)
(31,430)
Income (loss) from continuing operations
18,438
24,083
20,291
18,575
Discontinued operations:
        
Income (loss) from discontinued operations
--
--
--
--
Realized gains (losses) and unrealized losses
        
  on disposition of rental property, net
--
--
--
--
Total discontinued operations, net
--
--
--
--
Net income (loss)
18,438
24,083
20,291
18,575
Noncontrolling interest in consolidated joint ventures
94
96
102
110
Noncontrolling interest in Operating Partnership
(2,338)
(3,015)
(2,560)
(2,456)
Noncontrolling interest in discontinued operations
--
--
--
--
Preferred stock dividends
(72)
(664)
(500)
(500)
Net income (loss) available to common shareholders
$  16,122
$  20,500
$  17,333
$  15,729
         
Basic earnings per common share:
        
Income (loss) from continuing operations
$      0.18
$      0.24
$      0.20
$      0.19
Discontinued operations
--
--
--
--
Net income (loss) available to common shareholders
$      0.18
$      0.24
$      0.20
$      0.19
         
Diluted earnings per common share:
        
Income (loss) from continuing operations
$      0.18
$      0.24
$      0.20
$      0.19
Discontinued operations
--
--
--
--
Net income (loss) available to common shareholders
$      0.18
$      0.24
$      0.20
$      0.19
         
Dividends declared per common share
$      0.45
$      0.45
$      0.45
$      0.45
Quarter Ended 2010
December 31
September 30
June 30
March 31
Total revenues
$192,156
$197,956
$202,785
$194,583
Operating and other expenses
67,913
73,089
70,394
70,668
Direct construction costs
12,667
15,884
21,411
10,293
General and administrative
8,939
8,992
8,658
8,414
Depreciation and amortization
47,226
47,978
47,474
48,490
Impairment charge on rental property
9,521
--
--
--
Total expenses
146,266
145,943
147,937
137,865
Operating Income
45,890
52,013
54,848
56,718
Interest expense
(35,982)
(36,941)
(37,335)
(39,071)
Interest and other investment income
13
34
18
21
Equity in earnings (loss) of unconsolidated
        
joint ventures
2,063
475
260
(522)
Loss from early extinguishment of debt
(3,752)
--
--
--
Gain on reduction of other obligations
--
--
--
--
Total other (expense) income
(37,658)
(36,432)
(37,057)
(39,572)
Income (loss) from continuing operations
8,232
15,581
17,791
17,146
Discontinued operations:
        
Income (loss) from discontinued operations
--
--
11
231
Realized gains (losses) and unrealized losses
        
  on disposition of rental property, net
--
--
4,447
--
Total discontinued operations, net
--
--
4,458
231
Net income (loss)
8,232
15,581
22,249
17,377
Noncontrolling interest in consolidated joint ventures
(19)
108
86
87
Noncontrolling interest in Operating Partnership
(1,086)
(2,150)
(2,475)
(2,422)
Noncontrolling interest in discontinued operations
--
--
(635)
(33)
Preferred stock dividends
(500)
(500)
(500)
(500)
Net income (loss) available to common shareholders
$    6,627
$  13,039
$  18,725
$  14,509
         
Basic earnings per common share:
        
Income (loss) from continuing operations
$      0.09
$      0.16
$      0.19
$      0.18
Discontinued operations
--
--
0.05
--
Net income (loss) available to common shareholders
$      0.09
$      0.16
$      0.24
$      0.18
         
Diluted earnings per common share:
        
Income (loss) from continuing operations
$      0.09
$      0.16
$      0.19
$      0.18
Discontinued operations
--
--
0.05
--
Net income (loss) available to common shareholders
$      0.09
$      0.16
$      0.24
$      0.18
         
Dividends declared per common share
$      0.45
$      0.45
$      0.45
$      0.45