ACQUISITIONS (Schedule of Acquistions) (Details)	1 Months Ended			3 Months Ended				12 Months Ended
	Nov. 30, 2015	Jun. 30, 2015	Jan. 31, 2015	Mar. 31, 2016 USD ($)	Dec. 31, 2015 USD ($) ft²	Sep. 30, 2015 USD ($) ft²	Mar. 31, 2015 USD ($) ft²	Dec. 31, 2015 USD ($) ft²	Nov. 04, 2015	Aug. 29, 2014
Business Acquisition [Line Items]
Long-term Debt				$ 1,735,926,000	$ 1,694,841,000			$ 1,694,841,000
Controlling interest percentage				52.80%					1.80%	51.00%
Retail Site [Member]
Business Acquisition [Line Items]
Square Footage Acquired | ft²								1,939,499
Purchase Price								$ 325,100,000
Acquired interest				100.00%
Fig Garden Village [Member] | Retail Site [Member]
Business Acquisition [Line Items]
Date Acquired		Jun. 03, 2015
Square Footage Acquired | ft²						301,459
Purchase Price						$ 106,100,000
Long-term Debt				$ 74,200,000
Interest rate				4.14%
Debt Instrument, Interest Rate Terms				P5Y
Amortization term				30 years
The Shoppes at Carlsbad [Member] | Retail Site [Member]
Business Acquisition [Line Items]
Date Acquired	Nov. 12, 2015
Square Footage Acquired | ft²					1,117,040
Purchase Price					$ 170,000,000
Issuance of Series A Preferred Units				$ 140,000,000
Mt. Shasta Mall [Member] | Retail Site [Member]
Business Acquisition [Line Items]
Date Acquired			Jan. 28, 2015
Square Footage Acquired | ft²							521,000
Purchase Price							$ 49,000,000
Long-term Debt				$ 31,900,000
Interest rate				4.19%
Non Recourse Mortgage Loan [Member] | Mt. Shasta Mall [Member]
Business Acquisition [Line Items]
Amortization term				30 years