Related-Party Transactions - Additional Information (Detail) (USD $)	6 Months Ended
	Jun. 30, 2014
FUR Advisors [Member]
Related Party Transaction [Line Items]
Percentage of equity contributions	1.50%
Percentage of equity contributions by unaffiliated third parties	0.25%
Payable to related parties included in related party fees payable	$ 2,399,000
Winthrop Management LP [Member]
Related Party Transaction [Line Items]
Payable to related parties included in related party fees payable	$ 372,000