Related Party Transactions (Details) (USD $)	Dec. 31, 2012	Dec. 31, 2011
Total related-party amounts payable	$ 1,822,567	$ 1,791,440
Asset Management [Member]
Total related-party amounts payable	426,938	562,732
Acquisitions Fees [Member]
Total related-party amounts payable	322,440	81,776
Financing Fees [Member]
Total related-party amounts payable	5,891	14,491
Reimbursable Operating Expenses [Member]
Total related-party amounts payable	431,850	900,512
Reimbursable Offering Costs [Member]
Total related-party amounts payable	197,300	171,099
Reimbursable Organizational Costs [Member]
Total related-party amounts payable	49,931	49,931
Others [Member]
Total related-party amounts payable	$ 388,217	$ 10,899