Property, Plant, and Equipment - Schedule of Loss (Gain) on Sale or Write down of Assets (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Property, Plant and Equipment [Line Items]
Write-down of assets	$ (3,907)	$ (9,059)	$ (40,610)	$ (15,909)
(Loss) gain on sale or write down of assets, net	(3,867)	(9,059)	(40,570)	(15,375)
Write-down of non-real estate assets	(2,793)		(2,793)
Wilton Mall
Property, Plant and Equipment [Line Items]
Write-down of assets			(30,063)
Paradise Valley Mall
Property, Plant and Equipment [Line Items]
Write-down of assets			(6,640)
Land
Property, Plant and Equipment [Line Items]
Gain on sale	$ 40	$ 0	$ 40	$ 534