Property, net - Schedule of Loss (Gain) on Sale or Write down of Assets (Details) - USD ($) $ in Thousands			12 Months Ended
	Aug. 31, 2018	Nov. 16, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Mar. 01, 2018
Property, Plant and Equipment [Line Items]
Write-down of assets			$ (16,285)	$ (82,745)	$ (23,154)
(Loss) gain on sale or write down of assets, net			(11,909)	(31,825)	42,446
Outside partner interest of the operating partnership						75.00%
Impairment losses			(16,285)	(82,745)	(23,154)
Promenade at Casa Grande
Property, Plant and Equipment [Line Items]
Write-down of assets				(1,043)	(10,072)
Gain on disposal				(311)
Impairment losses				(1,043)	(10,072)
South Park Mall
Property, Plant and Equipment [Line Items]
Write-down of assets				(36,338)
Impairment losses				(36,338)
La Cumbre Plaza
Property, Plant and Equipment [Line Items]
Write-down of assets				(7,907)
Impairment losses				(7,907)
Two freestanding stores
Property, Plant and Equipment [Line Items]
Write-down of assets				(7,494)
Impairment losses				(7,494)
Southridge Center
Property, Plant and Equipment [Line Items]
Write-down of assets				(1,697)	(12,036)
Impairment losses				(1,697)	(12,036)
Westside Pavilion | Joint venture
Property, Plant and Equipment [Line Items]
Gain on sale of assets	$ 46,242			$ 46,242
Outside partner interest of the operating partnership	75.00%			75.00%
Cascade and Northgate Malls
Property, Plant and Equipment [Line Items]
Gain on disposal					59,577
500 North Michigan Avenue
Property, Plant and Equipment [Line Items]
Gain on disposal		$ 14,597
Property
Property, Plant and Equipment [Line Items]
Gain on sale of assets			0	$ 45,931	74,174
Land
Property, Plant and Equipment [Line Items]
Gain on sale of assets			4,376	4,989	1,564
Non-real estate
Property, Plant and Equipment [Line Items]
(Loss) gain on sale or write down of assets, net			$ 0	$ 0	$ (10,138)