Quarterly Financial Data (Unaudited) (Tables)

12 Months Ended

Dec. 31, 2013

Schedule of Quarterly Financial Information [Table Text Block]

	First Quarter			Second Quarter			Third Quarter		Fourth Quarter
2012	3/31			6/30			9/30		12/31
Total revenues (2)	$	414,037		$	431,910		$	449,072	$	452,483
Operating income (2)	102,110			121,745			142,020		148,247
(Loss) income from continuing operations (2)	(25,394		)	(6,340		)	91,269		100,763
Discontinued operations, net (2)	177,561			114,655			145,054		283,636
Net income *	152,167			108,315			236,323		384,399
Net income available to Common Shares	141,833			99,797			218,603		365,979
Earnings per share – basic:
Net income available to Common Shares	$	0.47		$	0.33		$	0.73	$	1.18
Weighted average Common Shares outstanding	298,805			300,193			301,336		310,398
Earnings per share – diluted:
Net income available to Common Shares	$	0.47		$	0.33		$	0.72	$	1.17
Weighted average Common Shares outstanding	298,805			300,193			318,773		327,108

(2) The amounts presented for the four quarters of 2012 are not equal to the same amounts previously reported in the Form 8-K filed with the SEC on June 17, 2013 (for the first and fourth quarters of 2012), the second quarter 2013 Form 10-Q filed with the SEC on August 8, 2013 (for the second quarter of 2012) and the third quarter 2013 Form 10-Q filed with the SEC on November 7, 2013 (for the third quarter of 2012) as a result of changes in discontinued operations due to additional property sales which occurred throughout 2013.

	First Quarter			Second Quarter			Third Quarter			Fourth Quarter
2013	3/31			6/30			9/30			12/31
Total revenues (1)	$	504,722		$	617,217		$	626,629		$	639,134
Operating income (1)	104,246			63,977			120,396			223,669
(Loss) income from continuing operations (1)	(165,339		)	(58,511		)	(13,465		)	69,141
Discontinued operations, net (1)	1,226,373			395,243			405,182			46,729
Net income *	1,061,034			336,732			391,717			115,870
Net income available to Common Shares	1,016,650			323,723			376,155			109,940
Earnings per share – basic:
Net income available to Common Shares	$	3.01		$	0.90		$	1.05		$	0.31
Weighted average Common Shares outstanding	337,532			359,653			359,811			359,919
Earnings per share – diluted:
Net income available to Common Shares	$	3.01		$	0.90		$	1.05		$	0.30
Weighted average Common Shares outstanding	337,532			359,653			359,811			375,860

(1) The amounts presented for the first three quarters of 2013 are not equal to the same amounts previously reported in the respective Form 10-Q’s filed with the SEC for each period as a result of changes in discontinued operations due to additional property sales which occurred throughout 2013.

Quarterly of Financial Information Previously Reported Reconciliation [Table Text Block]

Below is a reconciliation to the amounts previously reported:

	First Quarter			Second Quarter			Third Quarter			Fourth Quarter
2012	3/31			6/30			9/30			12/31
Total revenues previously reported in June 2013 Form 8-K/Form 10-Q	$	446,448		$	448,351		$	451,699		$	485,868
Total revenues subsequently reclassified to discontinued operations	(32,411		)	(16,441		)	(2,627		)	(33,385		)
Total revenues disclosed in Form 10-K	$	414,037		$	431,910		$	449,072		$	452,483
Operating income previously reported in June 2013 Form 8-K/Form    10-Q	$	114,476		$	128,560		$	142,932		$	162,109
Operating income subsequently reclassified to discontinued operations	(12,366		)	(6,815		)	(912		)	(13,862		)
Operating income disclosed in Form 10-K	$	102,110		$	121,745		$	142,020		$	148,247
(Loss) income from continuing operations previously reported in     June 2013 Form 8-K/Form 10-Q	$	(13,426	)	$	474		$	92,181		$	114,239
Income from continuing operations subsequently reclassified to discontinued operations	(11,968		)	(6,814		)	(912		)	(13,476		)
(Loss) income from continuing operations disclosed in Form 10-K	$	(25,394	)	$	(6,340	)	$	91,269		$	100,763
Discontinued operations, net previously reported in June 2013     Form 8-K/Form 10-Q	$	165,593		$	107,841		$	144,142		$	270,160
Discontinued operations, net from properties sold subsequent to the respective reporting period	11,968			6,814			912			13,476
Discontinued operations, net disclosed in Form 10-K	$	177,561		$	114,655		$	145,054		$	283,636

* The Company did not have any extraordinary items or cumulative effect of change in accounting principle during the years ended December 31, 2013 and 2012. Therefore, income before extraordinary items and cumulative effect of change in accounting principle is not shown as it was equal to the net income amounts disclosed above.

Below is a reconciliation to the amounts previously reported:

	First Quarter			Second Quarter			Third Quarter
2013	3/31			6/30			9/30
Total revenues previously reported in Form 10-Q	$	539,162		$	635,078		$	629,446
Total revenues subsequently reclassified to discontinued operations	(34,440		)	(17,861		)	(2,817		)
Total revenues disclosed in Form 10-K	$	504,722		$	617,217		$	626,629
Operating income previously reported in Form 10-Q	$	117,529		$	71,033		$	121,394
Operating income subsequently reclassified to discontinued operations	(13,283		)	(7,056		)	(998		)
Operating income disclosed in Form 10-K	$	104,246		$	63,977		$	120,396
(Loss) from continuing operations previously reported in Form 10-Q	$	(153,352	)	$	(51,455	)	$	(12,467	)
(Loss) from continuing operations subsequently reclassified to discontinued operations	(11,987		)	(7,056		)	(998		)
(Loss) from continuing operations disclosed in Form 10-K	$	(165,339	)	$	(58,511	)	$	(13,465	)
Discontinued operations, net previously reported in Form 10-Q	$	1,214,386		$	388,187		$	404,184
Discontinued operations, net from properties sold subsequent to the respective reporting period	11,987			7,056			998
Discontinued operations, net disclosed in Form 10-K	$	1,226,373		$	395,243		$	405,182

Operating Partnership [Member]

Schedule of Quarterly Financial Information [Table Text Block]

	First Quarter			Second Quarter			Third Quarter			Fourth Quarter
2013	3/31			6/30			9/30			12/31
Total revenues (1)	$	504,722		$	617,217		$	626,629		$	639,134
Operating income (1)	104,246			63,977			120,396			223,669
(Loss) income from continuing operations (1)	(165,339		)	(58,511		)	(13,465		)	69,141
Discontinued operations, net (1)	1,226,373			395,243			405,182			46,729
Net income *	1,061,034			336,732			391,717			115,870
Net income available to Units	1,059,973			336,511			390,991			114,271
Earnings per Unit – basic:
Net income available to Units	$	3.01		$	0.90		$	1.05		$	0.31
Weighted average Units outstanding	351,255			373,403			373,547			373,643
Earnings per Unit – diluted:
Net income available to Units	$	3.01		$	0.90		$	1.05		$	0.30
Weighted average Units outstanding	351,255			373,403			373,547			375,860

(1) The amounts presented for the first three quarters of 2013 are not equal to the same amounts previously reported in the respective Form 10-Q’s filed with the SEC for each period as a result of changes in discontinued operations due to additional property sales which occurred throughout 2013.

	First Quarter			Second Quarter			Third Quarter		Fourth Quarter
2012	3/31			6/30			9/30		12/31
Total revenues (2)	$	414,037		$	431,910		$	449,072	$	452,483
Operating income (2)	102,110			121,745			142,020		148,247
(Loss) income from continuing operations (2)	(25,394		)	(6,340		)	91,269		100,763
Discontinued operations, net (2)	177,561			114,655			145,054		283,636
Net income *	152,167			108,315			236,323		384,399
Net income available to Units	148,251			104,529			229,099		382,974
Earnings per Unit – basic:
Net income available to Units	$	0.47		$	0.33		$	0.73	$	1.18
Weighted average Units outstanding	312,011			314,255			315,513		324,364
Earnings per Unit – diluted:
Net income available to Units	$	0.47		$	0.33		$	0.72	$	1.17
Weighted average Units outstanding	312,011			314,255			318,773		327,108

(2) The amounts presented for the four quarters of 2012 are not equal to the same amounts previously reported in the Form 8-K filed with the SEC on June 17, 2013 (for the first and fourth quarters of 2012), the second quarter 2013 Form 10-Q filed with the SEC on August 8, 2013 (for the second quarter of 2012) and the third quarter 2013 Form 10-Q filed with the SEC on November 7, 2013 (for the third quarter of 2012) as a result of changes in discontinued operations due to additional property sales which occurred throughout 2013.

Quarterly of Financial Information Previously Reported Reconciliation [Table Text Block]

Below is a reconciliation to the amounts previously reported:

	First Quarter			Second Quarter			Third Quarter			Fourth Quarter
2012	3/31			6/30			9/30			12/31
Total revenues previously reported in June 2013 Form 8-K/Form 10-Q	$	446,448		$	448,351		$	451,699		$	485,868
Total revenues subsequently reclassified to discontinued operations	(32,411		)	(16,441		)	(2,627		)	(33,385		)
Total revenues disclosed in Form 10-K	$	414,037		$	431,910		$	449,072		$	452,483
Operating income previously reported in June 2013 Form 8-K/Form 10-Q	$	114,476		$	128,560		$	142,932		$	162,109
Operating income subsequently reclassified to discontinued operations	(12,366		)	(6,815		)	(912		)	(13,862		)
Operating income disclosed in Form 10-K	$	102,110		$	121,745		$	142,020		$	148,247
(Loss) income from continuing operations previously reported in June 2013 Form 8-K/Form 10-Q	$	(13,426	)	$	474		$	92,181		$	114,239
Income from continuing operations subsequently reclassified to discontinued operations	(11,968		)	(6,814		)	(912		)	(13,476		)
(Loss) income from continuing operations disclosed in Form 10-K	$	(25,394	)	$	(6,340	)	$	91,269		$	100,763
Discontinued operations, net previously reported in June 2013 Form 8-K/Form 10-Q	$	165,593		$	107,841		$	144,142		$	270,160
Discontinued operations, net from properties sold subsequent to the respective reporting period	11,968			6,814			912			13,476
Discontinued operations, net disclosed in Form 10-K	$	177,561		$	114,655		$	145,054		$	283,636

* The Operating Partnership did not have any extraordinary items or cumulative effect of change in accounting principle during the years ended December 31, 2013 and 2012. Therefore, income before extraordinary items and cumulative effect of change in accounting principle is not shown as it was equal to the net income amounts disclosed above.

Below is a reconciliation to the amounts previously reported:

	First Quarter			Second Quarter			Third Quarter
2013	3/31			6/30			9/30
Total revenues previously reported in Form 10-Q	$	539,162		$	635,078		$	629,446
Total revenues subsequently reclassified to discontinued operations	(34,440		)	(17,861		)	(2,817		)
Total revenues disclosed in Form 10-K	$	504,722		$	617,217		$	626,629
Operating income previously reported in Form 10-Q	$	117,529		$	71,033		$	121,394
Operating income subsequently reclassified to discontinued operations	(13,283		)	(7,056		)	(998		)
Operating income disclosed in Form 10-K	$	104,246		$	63,977		$	120,396
(Loss) from continuing operations previously reported in Form 10-Q	$	(153,352	)	$	(51,455	)	$	(12,467	)
(Loss) from continuing operations subsequently reclassified to discontinued operations	(11,987		)	(7,056		)	(998		)
(Loss) from continuing operations disclosed in Form 10-K	$	(165,339	)	$	(58,511	)	$	(13,465	)
Discontinued operations, net previously reported in Form 10-Q	$	1,214,386		$	388,187		$	404,184
Discontinued operations, net from properties sold subsequent to the respective reporting period	11,987			7,056			998
Discontinued operations, net disclosed in Form 10-K	$	1,226,373		$	395,243		$	405,182