SEGMENT REPORTING (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012
Segment Reporting Information [Line Items]
Number of Reportable Segments			3
Revenues	$ 40,318	$ 28,831	$ 121,891	$ 81,033
Property operating expenses, other operating and real estate taxes	11,732	8,840	31,869	25,014
General and administrative	5,335	5,517	17,261	16,636
Income before depreciation and amortization and interest and other finance expense	23,251	14,474	72,761	39,383
Depreciation and amortization	10,450	7,376	29,278	20,671
Interest and other finance expense	10,517	6,085	29,562	16,547
Real estate at cost	1,683,424	1,163,523	1,683,424	1,163,523
Total assets	2,349,368	1,869,890	2,349,368	1,869,890	1,908,440
Expenditures for redevelopment and improvements	35,982	14,109	79,549	55,817
Expenditures for redevelopment and improvements				55,817
Acquisition of real estate	30,975	26,093	140,075	137,208
Income (Loss) from Equity Method Investments	4,209	(2,538)	7,274	1,997
Income tax provision	(186)	104	(53)	(1,125)
Impairment of asset	0	0	(1,500)	0
Operating income from discontinued operations	2,835	2,159	6,100	9,030
Gain on sale of properties	0	5,917	4,191	8,585
Net income	9,142	6,655	29,933	20,652
Net income attributable to noncontrolling interests	343	926	(2,068)	(2,223)
Net income attributable to Common Shareholders	9,485	7,581	27,865	18,429
Core Portfolio
Segment Reporting Information [Line Items]
Revenues	28,115	17,794	82,252	50,166
Property operating expenses, other operating and real estate taxes	7,723	5,687	21,098	14,960
General and administrative	4,954	4,948	16,042	15,200
Income before depreciation and amortization and interest and other finance expense	15,438	7,159	45,112	20,006
Depreciation and amortization	7,890	4,379	21,187	12,016
Interest and other finance expense	6,683	4,184	19,169	11,352
Real estate at cost	998,711	608,971	998,711	608,971
Total assets	993,472	605,694	993,472	605,694
Expenditures for redevelopment and improvements	5,246	(915)	8,957	13,333
Acquisition of real estate	11,800	11,492	120,900	78,370
Opportunity Funds
Segment Reporting Information [Line Items]
Revenues	9,234	9,116	30,374	24,740
Property operating expenses, other operating and real estate taxes	4,009	3,153	10,771	10,054
General and administrative	381	569	1,219	1,436
Income before depreciation and amortization and interest and other finance expense	4,844	5,394	18,384	13,250
Depreciation and amortization	2,560	2,997	8,091	8,655
Interest and other finance expense	3,834	1,901	10,393	5,195
Real estate at cost	684,713	554,552	684,713	554,552
Total assets	1,260,544	1,183,430	1,260,544	1,183,430
Expenditures for redevelopment and improvements	30,736	15,024	70,592	42,484
Acquisition of real estate	19,175	14,601	19,175	58,838
Notes Receivable
Segment Reporting Information [Line Items]
Revenues	2,969	1,921	9,265	6,127
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	2,969	1,921	9,265	6,127
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	95,352	80,766	95,352	80,766
Expenditures for redevelopment and improvements	0	0	0	0
Acquisition of real estate	$ 0	$ 0	$ 0	$ 0