SEGMENT REPORTING (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015 USD ($)	Sep. 30, 2014 USD ($)	Sep. 30, 2015 USD ($) segment	Sep. 30, 2014 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments | segment			3
Revenues	$ 56,852	$ 47,660	$ 162,494	$ 143,856
Property operating expenses, other operating and real estate taxes	(12,853)	(12,424)	(42,210)	(38,119)
General and administrative expenses	(7,603)	(7,123)	(23,140)	(20,898)
Depreciation and amortization	(17,461)	(12,884)	(45,022)	(36,055)
Impairment of asset	0	0	(5,000)	0
Operating income	18,935	15,229	47,122	48,784
Equity in earnings of unconsolidated affiliates	2,195	2,923	12,194	7,382
Gain on disposition of property of unconsolidated affiliates	6,938	102,855	24,043	102,855
Loss on debt extinguishment	0	0	(134)	(269)
Gain on disposition of properties	79	190	89,063	13,138
Interest and other finance expense	(9,345)	(10,142)	(28,130)	(30,327)
Income tax (provision) benefit	(698)	17	(2,059)	(68)
Income from continuing operations	18,104	111,072	142,099	141,495
Gain on disposition of property	0	0	0	560
Net income	18,104	111,072	142,099	142,055
Continuing operations	(4,328)	(82,508)	(85,281)	(79,971)
Discontinued operations	0	0	0	(461)
Net income attributable to noncontrolling interests	(4,328)	(82,508)	(85,281)	(80,432)
Net income attributable to Common Shareholders	13,776	28,564	56,818	61,623
Real Estate at Cost	2,645,705	2,115,724	2,645,705	2,115,724
Total Assets	2,968,084	2,454,651	2,968,084	2,454,651
Acquisition of Real Estate	19,600	29,378	292,671	136,978
Investment in Redevelopment and Improvements	54,115	36,736	159,360	105,049
Core Portfolio
Segment Reporting Information [Line Items]
Revenues	37,744	31,291	110,930	91,974
Property operating expenses, other operating and real estate taxes	(8,885)	(8,491)	(26,811)	(23,984)
General and administrative expenses	(6,963)	(6,586)	(21,171)	(19,237)
Depreciation and amortization	(13,979)	(9,418)	(34,454)	(26,051)
Impairment of asset			(5,000)
Operating income	7,917	6,796	23,494	22,702
Equity in earnings of unconsolidated affiliates	434	118	1,567	441
Gain on disposition of property of unconsolidated affiliates	0	0	0	0
Loss on debt extinguishment			0	0
Gain on disposition of properties	0	190	0	12,577
Interest and other finance expense	(7,203)	(6,891)	(21,000)	(20,718)
Income tax (provision) benefit	(461)	(71)	(866)	(84)
Income from continuing operations				14,918
Gain on disposition of property				0
Net income	687	142	3,195	14,918
Continuing operations				(2,918)
Discontinued operations				0
Net income attributable to noncontrolling interests	(686)	(1,465)	401	(2,918)
Net income attributable to Common Shareholders	1	(1,323)	3,596	12,000
Real Estate at Cost	1,574,258	1,280,087	1,574,258	1,280,087
Total Assets	1,656,002	1,289,107	1,656,002	1,289,107
Acquisition of Real Estate	19,600	29,378	188,835	136,978
Investment in Redevelopment and Improvements	4,486	650	14,110	3,711
Funds
Segment Reporting Information [Line Items]
Revenues	11,783	13,363	36,846	39,938
Property operating expenses, other operating and real estate taxes	(3,968)	(3,933)	(15,399)	(14,135)
General and administrative expenses	(640)	(537)	(1,969)	(1,661)
Depreciation and amortization	(3,482)	(3,466)	(10,568)	(10,004)
Impairment of asset			0
Operating income	3,693	5,427	8,910	14,138
Equity in earnings of unconsolidated affiliates	1,761	2,805	10,627	6,941
Gain on disposition of property of unconsolidated affiliates	6,938	102,855	24,043	102,855
Loss on debt extinguishment			(134)	(269)
Gain on disposition of properties	79	0	89,063	561
Interest and other finance expense	(2,142)	(3,251)	(7,130)	(9,609)
Income tax (provision) benefit	(237)	88	(1,193)	16
Income from continuing operations				114,633
Gain on disposition of property				560
Net income	10,092	107,924	124,186	115,193
Continuing operations				(77,053)
Discontinued operations				(461)
Net income attributable to noncontrolling interests	(3,642)	(81,043)	(85,682)	(77,514)
Net income attributable to Common Shareholders	6,450	26,881	38,504	37,679
Real Estate at Cost	1,071,447	835,637	1,071,447	835,637
Total Assets	1,158,731	1,071,135	1,158,731	1,071,135
Acquisition of Real Estate	0	0	103,836	0
Investment in Redevelopment and Improvements	49,629	36,086	145,250	101,338
Structured Financing Portfolio
Segment Reporting Information [Line Items]
Revenues	7,325	3,006	14,718	11,944
Property operating expenses, other operating and real estate taxes	0	0	0	0
General and administrative expenses	0	0	0	0
Depreciation and amortization	0	0	0	0
Impairment of asset			0
Operating income	7,325	3,006	14,718	11,944
Equity in earnings of unconsolidated affiliates	0	0	0	0
Gain on disposition of property of unconsolidated affiliates	0	0	0	0
Loss on debt extinguishment			0	0
Gain on disposition of properties	0	0	0	0
Interest and other finance expense	0	0	0	0
Income tax (provision) benefit	0	0	0	0
Income from continuing operations				11,944
Gain on disposition of property				0
Net income	7,325	3,006	14,718	11,944
Continuing operations				0
Discontinued operations				0
Net income attributable to noncontrolling interests	0	0	0	0
Net income attributable to Common Shareholders	7,325	3,006	14,718	11,944
Real Estate at Cost	0	0	0	0
Total Assets	153,351	94,409	153,351	94,409
Acquisition of Real Estate	0	0	0	0
Investment in Redevelopment and Improvements	$ 0	$ 0	$ 0	$ 0