Property, net - Schedule of Loss (Gain) on Sale or Write down of Assets (Details) - USD ($) $ in Thousands		12 Months Ended
	Aug. 31, 2018	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Mar. 01, 2018
Property, Plant and Equipment [Line Items]
Impairment losses		$ (76,705)	$ (16,285)	$ (82,745)
(Loss) gain on sale or write down of assets, net		(68,112)	(11,909)	(31,825)
Outside partner interest of the operating partnership					75.00%
Write-down of assets		76,705	16,285	82,745
Write-down of non-real estate assets		4,154
Promenade at Casa Grande
Property, Plant and Equipment [Line Items]
Impairment losses				(1,043)
Write-down of assets				1,043
Gain on disposal				(311)
South Park Mall
Property, Plant and Equipment [Line Items]
Impairment losses				(36,338)
Write-down of assets				36,338
Wilton Mall
Property, Plant and Equipment [Line Items]
Impairment losses		(30,063)
Write-down of assets		30,063
Paradise Valley Mall
Property, Plant and Equipment [Line Items]
Impairment losses		(6,640)
Write-down of assets		6,640
La Cumbre Plaza
Property, Plant and Equipment [Line Items]
Impairment losses				(7,907)
Write-down of assets				7,907
Two freestanding stores
Property, Plant and Equipment [Line Items]
Impairment losses				(7,494)
Write-down of assets				7,494
Southridge Center
Property, Plant and Equipment [Line Items]
Impairment losses				(1,697)
Write-down of assets				1,697
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%
Property
Property, Plant and Equipment [Line Items]
Gain on sale of assets		0	0	$ 45,931
Land
Property, Plant and Equipment [Line Items]
Gain on sale of assets		8,593	$ 4,376	$ 4,989
Impairment losses		(5,047)
Write-down of assets		$ 5,047