Investments in and Advances to Joint Ventures - Additional Information (Detail) $ in Thousands	1 Months Ended		3 Months Ended		9 Months Ended
	Jun. 30, 2015 USD ($)	Mar. 31, 2015 Assets	Sep. 30, 2015 USD ($) ShoppingCenter	Sep. 30, 2014 USD ($)	Sep. 30, 2015 USD ($) ShoppingCenter	Sep. 30, 2014 USD ($)	Dec. 31, 2014 ShoppingCenter
Schedule Of Equity Method Investments [Line Items]
Gain (loss) on change in control of interests			$ 0	$ 3,984	$ 7,772	$ 87,814
Property Management Company [Member]
Schedule Of Equity Method Investments [Line Items]
Gain (loss) on change in control of interests	$ (6,500)
Percentage of ownership interest transferred	50.00%
Unconsolidated Joint Ventures [Member]
Schedule Of Equity Method Investments [Line Items]
Number of properties | ShoppingCenter			174		174		188
Coventry II Fund [Member]
Schedule Of Equity Method Investments [Line Items]
Gain (loss) on change in control of interests					$ 14,300
Ownership interest in joint venture		80.00%
Percentage of ownership interest transferred		20.00%
Number of properties sold | Assets		21