Related Party Transactions - Supervisory and Other Services - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Related Party Transaction [Line Items]
Basic annual fee	$ 24,000
Supervisory services fees	515,552	190,646
Additional payment of distributions received by the participants	10.00%
Required rate of return on cash investment for additional payment	14.00%
Original cash investment	7,000,000
Distributions profits interest	327,707	7,380
Fees for supervisory services	400,367	389,251
Other service fees	314,631	228,068
Profits interest	10.00%
Minimum [Member]
Related Party Transaction [Line Items]
Distributions profits interest	400,000
Effective July 1, 2010 [Member]
Related Party Transaction [Line Items]
Increase in basic payment plus annual Consumer Price Index adjustment	180,000
Effective July 1, 2012 [Member]
Related Party Transaction [Line Items]
Increase in basic payment plus annual Consumer Price Index adjustment	189,158
Special supervisory services [Member]
Related Party Transaction [Line Items]
Supervisory services fees	290,042	228,603
Malkin Holdings [Member]
Related Party Transaction [Line Items]
Basic annual fee	383,000
Lessee [Member]
Related Party Transaction [Line Items]
Distributions profits interest	$ 260,000	$ 260,004