Leases - Additional Information (Detail) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Operating Leased Assets [Line Items]
Operating lease revenues collected	$ 242,705	$ 241,998
Rents and other receivables	$ 0		$ 500,746
Maximum [Member]
Operating Leased Assets [Line Items]
Original lease terms of properties	20 years
Minimum [Member]
Operating Leased Assets [Line Items]
Original lease terms of properties	5 years