Consolidated Statements of Operations and Comprehensive Income (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Revenues:
Rental and related revenue	$ 228,883	$ 199,326	$ 668,230	$ 586,570
General contractor and service fee revenue	62,807	93,932	161,004	226,507
Revenues, total	291,690	293,258	829,234	813,077
Expenses:
Rental expenses	42,888	37,187	122,753	104,430
Real estate taxes	30,450	27,303	90,729	81,505
General contractor and other services expenses	59,392	87,719	142,925	209,519
Depreciation and amortization	103,594	90,202	296,791	264,435
Costs and expenses, total	236,324	242,411	653,198	659,889
Other operating activities:
Equity in earnings (loss) of unconsolidated companies	(27)	2,280	50,442	4,056
Gain on sale of properties	0	403	1,108	245
Earnings from sales of land	3,365	0	3,365	0
Undeveloped land carrying costs	(2,108)	(2,140)	(6,837)	(6,606)
Asset impairment charges	0	0	(3,777)	0
Other operating expenses	(47)	(130)	(150)	(591)
General and administrative expenses	(10,373)	(8,934)	(33,225)	(32,367)
Other operating transactions, total	(9,190)	(8,521)	10,926	(35,263)
Operating income	46,176	42,326	186,962	117,925
Other income (expenses):
Interest and other income, net	145	150	1,219	394
Interest expense	(58,100)	(58,812)	(176,005)	(175,726)
Acquisition-related activity	(726)	(954)	(2,506)	(2,563)
Income (Loss) from Continuing Operations before Income Taxes, Extraordinary Items, Noncontrolling Interest	(12,505)	(17,290)	9,670	(59,970)
Income Tax Benefit	4,500	103	4,500	103
Income (loss) from continuing operations	(8,005)	(17,187)	14,170	(59,867)
Discontinued operations:
Income (loss) before gain on sales	901	(1,970)	70	(4,699)
Gain on sale of depreciable properties	8,441	1,608	101,052	11,179
Income (loss) from discontinued operations	9,342	(362)	101,122	6,480
Net income (loss)	1,337	(17,549)	115,292	(53,387)
Dividends on preferred shares/units	(7,356)	(11,081)	(24,261)	(35,356)
Adjustments for redemption of preferred shares/units	0	0	(5,932)	(5,730)
Net (income) loss attributable to noncontrolling interests	(48)	400	(1,629)	1,371
Net income (loss) attributable to common shareholders/unitholders	(6,067)	(28,230)	83,470	(93,102)
Basic net income (loss) per common share/unit:
Continuing operations attributable to common shareholders/unitholders	$ (0.05)	$ (0.11)	$ (0.06)	$ (0.38)
Discontinued operations attributable to common shareholders/unitholders	$ 0.03	$ 0.00	$ 0.31	$ 0.02
Total	$ (0.02)	$ (0.11)	$ 0.25	$ (0.36)
Diluted net income (loss) per common share/unit:
Continuing operations attributable to common shareholders/unitholders	$ (0.05)	$ (0.11)	$ (0.06)	$ (0.38)
Discontinued operations attributable to common shareholders/unitholders	$ 0.03	$ 0.00	$ 0.31	$ 0.02
Total	$ (0.02)	$ (0.11)	$ 0.25	$ (0.36)
Weighted average number of common shares/units outstanding	324,895	270,289	320,810	265,153
Weighted average number of common shares/units and potential dilutive securities	324,895	270,289	325,380	265,153
Comprehensive income (loss):
Net income (loss)	1,337	(17,549)	115,292	(53,387)
Other comprehensive income:
Amortization of interest contracts	(116)	457	567	1,371
Other	(54)	(47)	522	(181)
Total other comprehensive income	(170)	410	1,089	1,190
Comprehensive income (loss)	1,167	(17,139)	116,381	(52,197)
Subsidiary of Common Parent [Member]
Revenues:
Rental and related revenue	228,883	199,326	668,230	586,570
General contractor and service fee revenue	62,807	93,932	161,004	226,507
Revenues, total	291,690	293,258	829,234	813,077
Expenses:
Rental expenses	42,888	37,187	122,753	104,430
Real estate taxes	30,450	27,303	90,729	81,505
General contractor and other services expenses	59,392	87,719	142,925	209,519
Depreciation and amortization	103,594	90,202	296,791	264,435
Costs and expenses, total	236,324	242,411	653,198	659,889
Other operating activities:
Equity in earnings (loss) of unconsolidated companies	(27)	2,280	50,442	4,056
Gain on sale of properties	0	403	1,108	245
Earnings from sales of land	3,365	0	3,365	0
Undeveloped land carrying costs	(2,108)	(2,140)	(6,837)	(6,606)
Asset impairment charges	0	0	(3,777)	0
Other operating expenses	(47)	(130)	(150)	(591)
General and administrative expenses	(10,373)	(8,934)	(33,225)	(32,367)
Other operating transactions, total	(9,190)	(8,521)	10,926	(35,263)
Operating income	46,176	42,326	186,962	117,925
Other income (expenses):
Interest and other income, net	145	150	1,219	394
Interest expense	(58,100)	(58,812)	(176,005)	(175,726)
Acquisition-related activity	(726)	(954)	(2,506)	(2,563)
Income (Loss) from Continuing Operations before Income Taxes, Extraordinary Items, Noncontrolling Interest	(12,505)	(17,290)	9,670	(59,970)
Income Tax Benefit	4,500	103	4,500	103
Income (loss) from continuing operations	(8,005)	(17,187)	14,170	(59,867)
Discontinued operations:
Income (loss) before gain on sales	901	(1,970)	70	(4,699)
Gain on sale of depreciable properties	8,441	1,608	101,052	11,179
Income (loss) from discontinued operations	9,342	(362)	101,122	6,480
Net income (loss)	1,337	(17,549)	115,292	(53,387)
Dividends on preferred shares/units	(7,356)	(11,081)	(24,261)	(35,356)
Adjustments for redemption of preferred shares/units	0	0	(5,932)	(5,730)
Noncontrolling Interest in Net Income (Loss) Joint Venture Partners, NonRedeemable	(140)	(59)	(487)	(365)
Net income (loss) attributable to common shareholders/unitholders	(6,159)	(28,689)	84,612	(94,838)
Basic net income (loss) per common share/unit:
Continuing operations attributable to common shareholders/unitholders	$ (0.05)	$ (0.11)	$ (0.06)	$ (0.38)
Discontinued operations attributable to common shareholders/unitholders	$ 0.03	$ 0.00	$ 0.31	$ 0.02
Total	$ (0.02)	$ (0.11)	$ 0.25	$ (0.36)
Diluted net income (loss) per common share/unit:
Continuing operations attributable to common shareholders/unitholders	$ (0.05)	$ (0.11)	$ (0.06)	$ (0.38)
Discontinued operations attributable to common shareholders/unitholders	$ 0.03	$ 0.00	$ 0.31	$ 0.02
Total	$ (0.02)	$ (0.11)	$ 0.25	$ (0.36)
Weighted average number of common shares/units outstanding	329,283	274,800	325,203	270,095
Weighted average number of common shares/units and potential dilutive securities	329,283	274,800	325,380	270,095
Comprehensive income (loss):
Net income (loss)	1,337	(17,549)	115,292	(53,387)
Other comprehensive income:
Amortization of interest contracts	(116)	457	567	1,371
Other	(54)	(47)	522	(181)
Total other comprehensive income	(170)	410	1,089	1,190
Comprehensive income (loss)	$ 1,167	$ (17,139)	$ 116,381	$ (52,197)