Condensed Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013
Statement of Cash Flows [Abstract]
Net income	$ 9,748	$ 57,725
Adjustments to reconcile net loss to net cash provided by operating activities:
Gain on sale of investment properties, including discontinued operations	7,867	57,764
Depreciation and amortization, including discontinued operations	69,354	27,113
Amortization of deferred financing costs	604	524
Net amortization of stock options and restricted stock	1,059	987
Effect of certain non-cash adjustments to rental revenues	(15,139)	(2,673)
Income Loss from Unconsolidated Joint Ventures	3,313	2,784
Operating distributions from unconsolidated joint ventures	3,165	2,942
Land and multi-family cost of sales, net of closing costs paid	255	904
Changes in other operating assets and liabilities:
Change in other receivables and other assets, net	(680)	(1,511)
Change in operating liabilities	(7,133)	(4,295)
Net cash provided by operating activities	50,053	21,168
CASH FLOWS FROM INVESTING ACTIVITIES:
Proceeds from investment property sales	29,050	116,006
Property acquisition, development, and tenant asset expenditures	(70,730)	(410,807)
Investment in unconsolidated joint ventures	(7,752)	(98)
Distributions from unconsolidated joint ventures	4,112	54,116
Collection of notes receivable	506	681
Change in notes receivable and other assets	(2,838)	(1,930)
Change in restricted cash	(1,094)	(378)
Net cash used in investing activities	(48,746)	(242,410)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from credit facility	213,325	174,925
Repayment of credit facility	(172,950)	(123,925)
Proceeds from other notes payable	0	1,292
Repayment of notes payable	(4,617)	(75,722)
Payments of Financing Costs	3,176	0
Proceeds from Issuance of Common Stock	98,519	165,100
Preferred Stock Redemption	(94,775)	(74,827)
Common dividends paid	(29,115)	(10,120)
Preferred dividends paid	(2,955)	(6,454)
Distributions to noncontrolling interests	(281)	(994)
Net cash provided by financing activities	3,975	49,275
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	5,282	(171,967)
CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD	975	176,892
CASH AND CASH EQUIVALENTS AT END OF PERIOD	6,257	4,925
Interest paid, net of amounts capitalized	14,256	9,719
Accrued property acquisition, development, and tenant asset expenditures	999	258
Transfer from operating properties to operating properties and related assets held for sale	0	49,435
Transfer from projects under development to operating properties	0	25,629
Transfer from other assets to projects under development	$ 0	$ 3,062