Interest Rate Derivative Agreements Footnote Tagging (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2015 USD ($)	Sep. 30, 2014 USD ($)	Sep. 30, 2015 USD ($) derivatives	Sep. 30, 2014 USD ($)	Dec. 31, 2014 USD ($)
Derivative [Line Items]
Number of Derivatives | derivatives			12
Derivative, Loss on Derivative		$ 154,000		$ 764,000
Payments for Derivative Instrument, Investing Activities			$ 562,088	$ 1,382,900
Derivative, Gain on Derivative	$ 1,300,000		2,000,000
Wells Fargo Bank, Royal Bank of Canada-3, SMBC Capital Markets, Inc-4 [Member]
Derivative [Line Items]
Derivative Asset, Notional Amount	$ 28,100,000		$ 28,100,000
Derivative, Fixed Interest Rate	3.00%		3.00%
Deriviative at purchase price			$ 573,000
SMBC Capital Markets, Inc 1 and 2 [Member]
Derivative [Line Items]
Derivative Asset, Notional Amount	$ 52,300,000		$ 52,300,000
Derivative, Maturity Date at a point in time	Mar. 01, 2017
Derivative, Fixed Interest Rate	1.00%		1.00%
Deriviative at purchase price			$ 151,000
SMBC Capital Markets, Inc-2 [Member]
Derivative [Line Items]
Derivative Asset, Notional Amount	$ 11,000,000		$ 11,000,000		$ 28,800,000
Derivative, Maturity Date at a point in time			Mar. 01, 2017
Payments for Derivative Instrument, Investing Activities			$ 0
Derivative, Fixed Interest Rate	1.00%		1.00%
Deriviative at purchase price			$ 150,500
Deutsche Bank [Member]
Derivative [Line Items]
Derivative Asset, Notional Amount	$ 93,305,000		$ 93,305,000
Derivative, Maturity Date at a point in time			Sep. 01, 2017
Derivative, Fixed Interest Rate	1.50%		1.50%
Deriviative at purchase price			$ 793,000
Swap [Member]
Derivative [Line Items]
Derivative, Fixed Interest Rate	2.00%		2.00%
Decatur-Angle [Member] | Swap [Member]
Derivative [Line Items]
Derivative, Gain on Derivative	$ 871,000
Derivative, Notional Amount	23,000,000		$ 23,000,000
Document Effective Date			Oct. 15, 2016
Derivative, Maturity Date			Oct. 15, 2021
Bruton Apartments [Member] | Swap [Member]
Derivative [Line Items]
Derivative, Loss on Derivative	669,000
Derivative, Notional Amount	$ 18,100,000		$ 18,100,000
Document Effective Date			Apr. 15, 2017
Derivative, Maturity Date			Apr. 15, 2022