Investments in Partially Owned Entities (Details 1) (USD $) In Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Partially Owned Property Income Statement Schedule
Operating revenue	$ 498,059	$ 447,379	$ 977,850	$ 876,559
Net operating (loss) income		271,674
Depreciation	159,087	162,697	321,181	302,964
General and administrative/other	(10,908)	(10,089)	(22,341)	(20,808)
Operating (loss) income	146,495	100,329	267,473	200,171
Interest and other income	281	2,625	1,292	4,845
Other expenses	(4,626)	(1,643)	(6,790)	(6,026)
Interest:
Expense incurred, net	(120,525)	(113,723)	(241,856)	(227,489)
Amortization of deferred financing costs	(4,444)	(2,300)	(7,454)	(5,295)
(Loss) before income and other taxes and discontinued operations	17,181	(14,712)	12,665	(33,794)
Income and other tax (expense) benefit	(203)	147	(387)	7
Net gain on sales of land parcels	4,217		4,217
Net gain on sales of discontinued operations	(558,482)	(217)	682,236	60,253
Net income	581,753	10,089	714,819	67,945
Co-invested in various properties with unrelated third parties [Member] | Consolidated Development Projects Held for and or Under Development [Member]
Partially Owned Property Income Statement Schedule
Operating expenses			124
Net operating (loss) income			(124)
General and administrative/other			103
Operating (loss) income			(227)
Interest and other income			4
Other expenses			(207)
Interest:
Expense incurred, net			(399)
(Loss) before income and other taxes and discontinued operations			(829)
Income and other tax (expense) benefit			(57)
Net gain on sales of land parcels			4,217
Net gain on sales of discontinued operations			169
Net income			3,500
Co-invested in various properties with unrelated third parties [Member] | Consolidated Development Projects Completed and Stabilized [Member]
Partially Owned Property Income Statement Schedule
Operating revenue			10,763
Operating expenses			3,848
Net operating (loss) income			6,915
Depreciation			(5,872)
General and administrative/other			5
Operating (loss) income			1,038
Interest and other income			4
Interest:
Expense incurred, net			(4,440)
Amortization of deferred financing costs			(1,337)
(Loss) before income and other taxes and discontinued operations			(4,735)
Net income			(4,735)
Co-invested in various properties with unrelated third parties [Member] | Consolidated Other [Member]
Partially Owned Property Income Statement Schedule
Operating revenue			28,261
Operating expenses			9,371
Net operating (loss) income			18,890
Depreciation			(7,491)
General and administrative/other			27
Operating (loss) income			11,372
Interest and other income			8
Other expenses			(14)
Interest:
Expense incurred, net			(6,785)
Amortization of deferred financing costs			(324)
(Loss) before income and other taxes and discontinued operations			4,257
Income and other tax (expense) benefit			(8)
Net income			4,249
Co-invested in various properties with unrelated third parties [Member]
Partially Owned Property Income Statement Schedule
Operating revenue			39,024
Operating expenses			13,343
Net operating (loss) income			25,681
Depreciation			(13,363)
General and administrative/other			135
Operating (loss) income			12,183
Interest and other income			16
Other expenses			(221)
Interest:
Expense incurred, net			(11,624)
Amortization of deferred financing costs			(1,661)
(Loss) before income and other taxes and discontinued operations			(1,307)
Income and other tax (expense) benefit			(65)
Net gain on sales of land parcels			4,217
Net gain on sales of discontinued operations			169
Net income			$ 3,014