Real Estate Activities - Dispositions of Assets (Detail) - Mall - USD ($)	1 Months Ended
	Aug. 31, 2017	Jan. 31, 2017
Beaver Valley Mall
Disposals [Line Items]
Capitalization rate		15.60%
Sale Price		$ 24,200
Crossroads Mall
Disposals [Line Items]
Capitalization rate		15.50%
Sale Price		$ 24,800
Logan Valley Mall
Disposals [Line Items]
Capitalization rate	16.50%
Sale Price	$ 33,200