Leases - Additional Information (Detail) (USD $)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012
Operating Leases [Line Items]
Operating lease revenues collected	$ 289,320	$ 281,025	$ 545,524	$ 536,550
Operating percentage rents	32,937	25,500	32,937	25,500	465,406
Rents and other receivables for unbilled percentage rents	$ 32,937		$ 32,937		$ 465,406
Maximum [Member]
Operating Leases [Line Items]
Original lease terms of properties			20 years
Minimum [Member]
Operating Leases [Line Items]
Original lease terms of properties			5 years