Indebtedness - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended				0 Months Ended	3 Months Ended	9 Months Ended	3 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Jan. 29, 2014 Interest Rate Swap	Sep. 30, 2014 Mortgages	Jan. 29, 2014 Unsecured Term Loan	Sep. 30, 2014 Mortgages	Sep. 30, 2014 Mortgages	Sep. 30, 2014 Senior Unsecured Notes
Debt Disclosure [Line Items]
Extinguishment of debt, amount								$ 65,558		$ 81,794
Gains (losses) on extinguishment of debt	(32)	(662)	(655)	(6,248)					655
Carrying value of industrial properties held under mortgage						744,826
Unsecured term loan, term							7 years
Unsecured term loan, face amount							200,000
Swaps, notional amount					$ 200,000