Condensed Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013
Parent Company [Member]
Cash flows from operating activities:
Consolidated net income	$ 49,100	$ 83,033
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, Amortization and Accretion, Net	(12)	(20)
Depreciation and amortization	162,099	68,236
Stock compensation expense	2,045	1,171
Proceeds from Stock Options Exercised	9,544	0
Redeemable stock issued	507	377
Amortization of debt premium	(14,648)	(505)
Gain from investments in real estate joint ventures	(2,878)	(101)
Loss on Extinguishment of Debt, Including Discontinued Operations	0	169
Derivative interest expense	402	484
Gain on Sale of Derivatives	(3,625)	0
Gain on Sale of Non-Depreciable Assets	(535)	0
Gain on sale of depreciable assets	(6,222)	0
Gain on sale of discontinued operations	(5,481)	(43,121)
Net casualty loss (gain) and other settlement proceeds	308	(451)
Changes in assets and liabilities:
Restricted cash	21,318	(279)
Other assets	11,134	(3,176)
Accounts payable	229	5,527
Accrued expenses and other	594	(2,239)
Security deposits	526	277
Net cash provided by operating activities	224,405	109,382
Cash flows from investing activities:
Purchases of real estate and other assets	(166,388)	(89,871)
Improvements to existing real estate assets	(43,176)	(22,494)
Construction Capital and Other Improvements	(3,420)	(2,137)
Renovations to Existing Real Estate Assets	(5,901)	(5,112)
Development	(29,393)	(20,816)
Distributions from real estate joint ventures	11,541	8,197
Contributions to real estate joint ventures	0	(183)
Proceeds from disposition of real estate assets	125,640	73,089
Funding of escrow for future acquisitions	(41,640)	(11,902)
Net cash used in investing activities	(152,737)	(71,229)
Cash flows from financing activities:
Net change in credit lines	(181,183)	2,000
Proceeds from Notes Payable	396,180	0
Principal payments on notes payable	(230,952)	(2,799)
Payment of deferred financing costs	(3,395)	(426)
Repurchase of common stock	(336)	(673)
Proceeds from issuances of common shares	575	24,968
Distributions to noncontrolling interests	(6,158)	(2,391)
Dividends paid on common shares	(109,414)	(59,115)
Net cash used in financing activities	(134,683)	(38,436)
Net decrease in cash and cash equivalents	(63,015)	(283)
Cash and cash equivalents, beginning of period	89,333	9,075
Cash and cash equivalents, end of period	26,318	8,792
Supplemental disclosure of cash flow information:
Interest paid	75,818	33,610
Income Taxes Paid	803	1,596
Supplemental disclosure of noncash investing and financing activities:
Conversion of units to shares of common stock	799	444
Accrued construction in progress	8,458	7,126
Interest capitalized	850	872
Marked-to-market adjustment on derivative instruments	1,633	19,916
Fair value adjustment on debt assumed	1,651	704
Notes Assumed	31,692	18,293
Limited Partner [Member]
Cash flows from operating activities:
Consolidated net income	49,100	71,293
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, Amortization and Accretion, Net	(12)	(20)
Depreciation and amortization	162,099	68,001
Stock compensation expense	2,045	1,171
Proceeds from Stock Options Exercised	9,544	0
Redeemable stock issued	507	377
Amortization of debt premium	(14,648)	(505)
Gain from investments in real estate joint ventures	(2,878)	(101)
Loss on Extinguishment of Debt, Including Discontinued Operations	0	169
Derivative interest expense	402	465
Gain on Sale of Derivatives	(3,625)	0
Gain on Sale of Non-Depreciable Assets	(535)	0
Gain on sale of depreciable assets	(6,222)	0
Gain on sale of discontinued operations	(5,481)	(31,779)
Net casualty loss (gain) and other settlement proceeds	308	(451)
Changes in assets and liabilities:
Restricted cash	21,318	(278)
Other assets	11,134	(2,076)
Accounts payable	229	5,552
Accrued expenses and other	594	(4,483)
Security deposits	526	296
Net cash provided by operating activities	224,405	107,631
Cash flows from investing activities:
Purchases of real estate and other assets	(166,388)	(89,871)
Improvements to existing real estate assets	(43,176)	(22,383)
Construction Capital and Other Improvements	(3,420)	(2,137)
Renovations to Existing Real Estate Assets	(5,901)	(5,112)
Development	(29,393)	(20,816)
Distributions from real estate joint ventures	11,541	8,197
Contributions to real estate joint ventures	0	(183)
Proceeds from disposition of real estate assets	125,640	56,386
Funding of escrow for future acquisitions	(41,640)	(11,902)
Net cash used in investing activities	(152,737)	(87,821)
Cash flows from financing activities:
Advances from General Partner	0	18,021
Net change in credit lines	(181,183)	2,000
Proceeds from Notes Payable	396,180	0
Principal payments on notes payable	(230,952)	(2,799)
Payment of deferred financing costs	(3,395)	(426)
Payments for Repurchase of Common Units	(336)	(673)
Proceeds from Issuance of Common Limited Partners Units	575	24,969
Distributions Paid on Common Units	(115,572)	(61,044)
Net cash used in financing activities	(134,683)	(19,952)
Net decrease in cash and cash equivalents	(63,015)	(142)
Cash and cash equivalents, beginning of period	89,333	8,934
Cash and cash equivalents, end of period	26,318	8,792
Supplemental disclosure of cash flow information:
Interest paid	75,818	33,610
Income Taxes Paid	803	1,596
Supplemental disclosure of noncash investing and financing activities:
Accrued construction in progress	8,458	7,126
Interest capitalized	850	872
Marked-to-market adjustment on derivative instruments	1,633	19,916
Fair value adjustment on debt assumed	1,651	704
Notes Assumed	$ 31,692	$ 18,293