Notes Payable and Accrued Interest (Details) - USD ($)	Jun. 30, 2016	Dec. 31, 2015
Notes Payable and Accrued Interest [Abstract]
Unamortized debt issuance costs	$ (2,440,500)	$ (2,814,000)
Notes payable and accrued interest	76,368,800	107,621,600
Credit Facility [Member]
Notes Payable and Accrued Interest [Abstract]
Credit Facility principal	78,800,000	110,400,000
Unamortized debt issuance costs	(2,440,500)	(2,814,000)
Credit Facility accrued interest	9,300	35,600
Notes payable and accrued interest	76,368,800	107,621,600
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	$ 71,200,000	$ 39,600,000
Weighted average interest rate on credit facility	3.81%	3.80%