Summary of Significant Accounting Policies - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Summary Of Significant Accounting Policies [Line Items]
Maximum maturity period for highly liquid investment	3 months
Building improvements, estimated useful life	39 years
Primary overage rent recorded period	12 months
Asset impairment charges	$ 0	$ 0
Aggregate net assets exceeded tax bases	3,322,972	1,854,000
External offering costs	1,752,344
Deferred offering costs	962,325	636,883
Offering costs due to Supervisor	621,233	127,671
Additional offering costs for work done by employees of Supervisor	151,070	109,560
Impact of error correction accumulated		213,500
Building [Member]
Summary Of Significant Accounting Policies [Line Items]
Building improvements program costs	51,677,946	44,605,623
Tenant improvements [Member]
Summary Of Significant Accounting Policies [Line Items]
Building improvements program costs	$ 7,072,323	$ 4,758,981