Notes Payable and Accrued Interest (Details) - USD ($)	Sep. 30, 2015	Dec. 31, 2014
Notes Payable and Accrued Interest [Abstract]
Unamortized debt issuance costs	$ (3,016,900)	$ (4,104,400)
Notes payable and accrued interest	119,436,900	129,486,200
Credit Facility [Member]
Notes Payable and Accrued Interest [Abstract]
Credit Facility principal	122,400,000	133,400,000
Unamortized debt issuance costs	(3,016,900)	(4,104,400)
Credit Facility accrued interest	53,800	190,600
Notes payable and accrued interest	119,436,900	129,486,200
Credit Facility [Abstract]
Credit facility maximum borrowing capacity	150,000,000
Credit facility potential maximum borrowing capacity	180,000,000
Unused amount of the credit facility	$ 27,600,000	$ 16,600,000
Weighted average interest rate on credit facility	3.86%	3.58%