SEGMENT REPORTING (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012
Segment Reporting Information [Line Items]
Number of Reportable Segments			3
Revenues	$ 45,936	$ 32,745	$ 93,236	$ 62,712
Property operating expenses, other operating and real estate taxes	11,897	10,645	24,242	20,241
General and administrative	6,301	5,205	11,927	11,130
Income before depreciation and amortization and interest and other finance expense	27,738	16,895	57,067	31,341
Depreciation and amortization	10,976	8,201	21,604	15,351
Interest and other finance expense	10,913	7,070	21,222	13,626
Real estate at cost	1,816,424	1,316,185	1,816,424	1,316,185
Total assets	2,310,544	1,503,765	2,310,544	1,503,765	1,908,440
Expenditures for redevelopment and improvements	25,626	18,756	43,567	41,705
Expenditures for redevelopment and improvements				38,918
Acquisition of real estate	22,500	62,426	109,100	111,115
Income (Loss) from Equity Method Investments	815	4,591	3,065	4,535
Income tax provision	(7)	(1,039)	133	(1,227)
Impairment of asset	(1,500)	0	(1,500)	0
Operating income from discontinued operations	266	3,332	663	5,659
Gain on sale of property	4,191	2,668	4,191	2,668
Net income	9,614	11,176	20,793	13,999
Net income attributable to noncontrolling interests	(857)	(4,337)	(2,413)	(3,150)
Net income attributable to Common Shareholders	8,757	6,839	18,380	10,849
Core Portfolio
Segment Reporting Information [Line Items]
Revenues	28,057	17,366	54,471	33,070
Property operating expenses, other operating and real estate taxes	6,811	4,468	13,912	9,007
General and administrative	5,872	4,600	11,345	10,252
Income before depreciation and amortization and interest and other finance expense	15,374	8,298	29,214	13,811
Depreciation and amortization	7,142	4,495	13,777	8,237
Interest and other finance expense	6,563	3,721	12,712	7,074
Real estate at cost	1,006,210	632,084	1,006,210	632,084
Total assets	1,100,356	750,634	1,100,356	750,634
Expenditures for redevelopment and improvements	3,255	12,778	3,711	19,984
Acquisition of real estate	22,500	50,689	109,100	66,878
Opportunity Funds
Segment Reporting Information [Line Items]
Revenues	14,480	13,202	32,006	25,436
Property operating expenses, other operating and real estate taxes	5,086	6,177	10,330	11,234
General and administrative	429	605	582	878
Income before depreciation and amortization and interest and other finance expense	8,965	6,420	21,094	13,324
Depreciation and amortization	3,834	3,706	7,827	7,114
Interest and other finance expense	4,350	3,349	8,510	6,552
Real estate at cost	810,214	684,101	810,214	684,101
Total assets	1,104,704	664,419	1,104,704	664,419
Expenditures for redevelopment and improvements	22,371	5,978	39,856	18,934
Acquisition of real estate	0	11,737	0	44,237
Notes Receivable
Segment Reporting Information [Line Items]
Revenues	3,399	2,177	6,759	4,206
Property operating expenses, other operating and real estate taxes	0	0	0	0
General and administrative	0	0	0	0
Income before depreciation and amortization and interest and other finance expense	3,399	2,177	6,759	4,206
Depreciation and amortization	0	0	0	0
Interest and other finance expense	0	0	0	0
Real estate at cost	0	0	0	0
Total assets	105,484	88,712	105,484	88,712
Expenditures for redevelopment and improvements	0	0	0	0
Acquisition of real estate	$ 0	$ 0	$ 0	$ 0