Derivatives - Additional Information (Detail) $ in Thousands	1 Months Ended	3 Months Ended	9 Months Ended
	Jul. 31, 2014 USD ($)	Sep. 30, 2015 USD ($) Agreement	Sep. 30, 2015 USD ($) Agreement	Sep. 30, 2014 USD ($)	Oct. 13, 2015 USD ($) Agreement	Jul. 28, 2014 USD ($)
Derivative Instruments [Line Items]
Loss recognized in income on derivatives (ineffective portion and amount excluded from effectiveness testing)			$ 500
Repayments of Secured Debt			272,776	$ 76,784
Estimate increase to interest expense		$ 4,300	4,300
Derivative Liability, Notional Amount, Ineffective						$ 40,000
Net loss		2,200	2,200
Fair value of derivatives in a net liability position		(6,000)	(6,000)
Termination value		6,500	$ 6,500
Interest expense, mark to market		$ 500
Interest rate swaps [Member]
Derivative Instruments [Line Items]
Number of derivative, interest rate swap agreement | Agreement		16	16
Derivative, Weighted average interest rate		1.55%	1.55%
Derivative, notional amount		$ 421,900	$ 421,900
Interest Rate Swap Twelve [Member]
Derivative Instruments [Line Items]
Maturity Date			Jan. 02, 2019
Settled Interest Rate Swaps [Member]
Derivative Instruments [Line Items]
Amortized period			10 years
The Gallery at Market East [Member]
Derivative Instruments [Line Items]
Repayments of Secured Debt	$ 25,800
Subsequent Event [Member] | Interest rate swaps [Member]
Derivative Instruments [Line Items]
Number of derivative, interest rate swap agreement | Agreement					5
Derivative, Weighted average interest rate					1.23%
Derivative, notional amount					$ 100,000