SEGMENT REPORTING (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016 USD ($)	Sep. 30, 2015 USD ($)	Sep. 30, 2016 USD ($) segment	Sep. 30, 2015 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments | segment			3
Revenues	$ 51,100	$ 56,852	$ 155,116	$ 162,494
Property operating expenses, other operating and real estate taxes	(14,515)	(12,853)	(37,791)	(42,210)
General and administrative expenses	(12,869)	(7,603)	(30,742)	(23,140)
Depreciation and amortization	(15,217)	(17,461)	(46,744)	(45,022)
Impairment of asset	0	0	0	(5,000)
Operating income	8,499	18,935	39,839	47,122
Equity in earnings (losses) of unconsolidated affiliates	(102)	2,195	3,592	12,194
Gain on disposition of property of unconsolidated affiliates	0	6,938	0	24,043
Loss on debt extinguishment	0	0	(15)	(134)
Gain on disposition of properties	0	79	81,965	89,063
Interest and other finance expense	(7,982)	(9,345)	(24,902)	(28,130)
Income tax provision	(89)	(698)	(123)	(2,059)
Net income	326	18,104	100,356	142,099
Net loss (income) attributable to noncontrolling interests	5,786	(4,328)	(47,401)	(85,281)
Net income attributable to Common Shareholders	6,112	13,776	52,955	56,818
Real Estate at Cost	3,019,789	2,578,580	3,019,789	2,578,580
Total Assets	3,578,519	2,973,699	3,578,519	2,973,699
Acquisition of Real Estate	274,329	52,800	292,909	273,071
Investment in Redevelopment and Improvements	38,531	64,751	94,421	105,245
Core Portfolio
Segment Reporting Information [Line Items]
Revenues	36,376	37,744	109,176	110,930
Property operating expenses, other operating and real estate taxes	(11,612)	(8,885)	(28,460)	(26,811)
General and administrative expenses	(11,915)	(6,963)	(28,955)	(21,171)
Depreciation and amortization	(12,428)	(13,979)	(37,629)	(34,454)
Impairment of asset				(5,000)
Operating income	421	7,917	14,132	23,494
Equity in earnings (losses) of unconsolidated affiliates	1,495	434	2,668	1,567
Gain on disposition of property of unconsolidated affiliates		0		0
Loss on debt extinguishment			0	0
Gain on disposition of properties		0	0	0
Interest and other finance expense	(6,431)	(7,203)	(20,308)	(21,000)
Income tax provision	(70)	(461)	(80)	(866)
Net income	(4,585)	687	(3,588)	3,195
Net loss (income) attributable to noncontrolling interests	60	(686)	(2,771)	1,340
Net income attributable to Common Shareholders	(4,525)	1	(6,359)	4,535
Real Estate at Cost	1,832,863	1,553,174	1,832,863	1,553,174
Total Assets	2,097,386	1,650,555	2,097,386	1,650,555
Acquisition of Real Estate	237,729	0	244,022	169,235
Investment in Redevelopment and Improvements	7,296	3,271	17,518	9,624
Funds
Segment Reporting Information [Line Items]
Revenues	7,479	11,783	26,642	36,846
Property operating expenses, other operating and real estate taxes	(2,903)	(3,968)	(9,331)	(15,399)
General and administrative expenses	(954)	(640)	(1,787)	(1,969)
Depreciation and amortization	(2,789)	(3,482)	(9,115)	(10,568)
Impairment of asset				0
Operating income	833	3,693	6,409	8,910
Equity in earnings (losses) of unconsolidated affiliates	(1,597)	1,761	924	10,627
Gain on disposition of property of unconsolidated affiliates		6,938		24,043
Loss on debt extinguishment			(15)	(134)
Gain on disposition of properties		79	81,965	89,063
Interest and other finance expense	(1,551)	(2,142)	(4,594)	(7,130)
Income tax provision	(19)	(237)	(43)	(1,193)
Net income	(2,334)	10,092	84,646	124,186
Net loss (income) attributable to noncontrolling interests	5,726	(3,642)	(44,630)	(86,621)
Net income attributable to Common Shareholders	3,392	6,450	40,016	37,565
Real Estate at Cost	1,186,926	1,025,406	1,186,926	1,025,406
Total Assets	1,214,317	1,154,213	1,214,317	1,154,213
Acquisition of Real Estate	36,600	52,800	48,887	103,836
Investment in Redevelopment and Improvements	31,235	61,480	76,903	95,621
Structured Financing Portfolio
Segment Reporting Information [Line Items]
Revenues	7,245	7,325	19,298	14,718
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	7,245	7,325	19,298	14,718
Equity in earnings (losses) of unconsolidated affiliates	0	0	0	0
Gain on disposition of property of unconsolidated affiliates		0		0
Loss on debt extinguishment			0	0
Gain on disposition of properties		0	0	0
Interest and other finance expense	0	0	0	0
Income tax provision	0	0	0	0
Net income	7,245	7,325	19,298	14,718
Net loss (income) attributable to noncontrolling interests	0	0	0	0
Net income attributable to Common Shareholders	7,245	7,325	19,298	14,718
Real Estate at Cost	0	0	0	0
Total Assets	266,816	168,931	266,816	168,931
Acquisition of Real Estate	0	0	0	0
Investment in Redevelopment and Improvements	$ 0	$ 0	$ 0	$ 0