DISPOSITIONS AND HELD FOR SALE - Summary (Details) $ in Thousands	1 Months Ended						12 Months Ended
	Jun. 30, 2019 USD ($)	Apr. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Jan. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Jan. 31, 2018 USD ($)	Dec. 31, 2020 USD ($) outparcel	Dec. 31, 2019 USD ($) outparcel joint_venture	Dec. 31, 2018 USD ($) outparcel
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain on sales of real estate assets							$ 4,696	$ 16,274	$ 19,001
Gross Sales Price								120,308
Net Sales Price								118,383
Gain					$ 7,471			8,246
Loss on impairment							213,358	$ 239,521	174,529
Number of joint venture | joint_venture								3
Gain (loss) on sale of outparcels								$ 33
Net Sales Price					53,402
Gross Sales Price					65,000
Acadiana Mall
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Loss on impairment									1,593
Net Sales Price				$ 4,000
Honey Creek Mall
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Loss on impairment		$ (239)	$ 2,284
The Forum at Grandview
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Loss on impairment	$ 8,582
Janesville Mall
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Loss on impairment						$ 18,061
Statesboro Crossing
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Percentage of net proceeds from sale						100.00%
Statesboro Crossing | Corporate Joint Venture
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Ownership interest in joint venture (as a percent)						50.00%
Statesboro Crossing | Consolidated Properties
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Ownership interest in joint venture (as a percent)						50.00%
Malls
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Loss on impairment							213,358
Malls | Cary Towne Center
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gross Sales Price								31,500
Net Sales Price								31,068
Malls | Honey Creek Mall
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gross Sales Price								14,600
Net Sales Price								14,360
Malls | Shopsat Hickory Point
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gross Sales Price								2,508
Net Sales Price								2,407
Gain								1,326
Malls | Janesville Mall
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net Sales Price					17,783
Gross Sales Price					18,000
Malls | College Square Mall
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain					742
All Other | Courtyardby Marriottat Pearland Town Center
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gross Sales Price								15,100
Net Sales Price								14,795
Gain								1,910
All Other | A850 Greenbriar Circle
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gross Sales Price								10,500
Net Sales Price								10,332
Gain								96
All Other | Krogerat Foothill Plaza
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gross Sales Price								2,350
Net Sales Price								2,267
Gain								1,139
All Other | The Forum at Grandview
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gross Sales Price								31,750
Net Sales Price								31,606
Gain								47
All Other | Barnes Nobleat High Point
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gross Sales Price								2,000
Net Sales Price								1,899
Gain								821
All Other | Dicks Sporting Goodsat Hanes Mall
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gross Sales Price								10,000
Net Sales Price								9,649
Gain								2,907
All Other | Gulf Coast Town Center Phase I I I
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain					2,236
Net Sales Price					8,769
Gross Sales Price					9,000
All Other | Statesboro Crossing
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain					3,215
Net Sales Price					10,532
Gross Sales Price					21,500
All Other | Parkway Plaza
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain					1,419
Net Sales Price					16,318
Gross Sales Price					16,500
All Other | Prior Sales Adjustment
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain					$ (141)
Outparcel Sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain on sales of real estate assets							$ 4,696	$ 6,434	$ 11,530
Number of stores sold (outparcel) | outparcel							8	5	12
Parkdale Self Storage L L C
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain (loss) related to land contributed								$ 1,627