Segments (Assets) (Details) - USD ($)		Jun. 30, 2017	Dec. 31, 2016	Jun. 30, 2016	Dec. 31, 2015
Segment Reporting Asset Reconciling Item [Line Items]
Land, buildings and improvements, net		$ 238,595,388	$ 246,969,993
Cash and cash equivalents		5,847,369	3,116,147	$ 5,518,204	$ 6,626,423
Other assets, net		5,451,230	5,745,982
TOTAL ASSETS		254,079,359	257,999,077
Significant Reconciling Items [Member]
Segment Reporting Asset Reconciling Item [Line Items]
Other assets, net		9,636,602	7,912,937
Office/Industrial Properties [Member] | Operating Segments [Member]
Segment Reporting Asset Reconciling Item [Line Items]
Land, buildings and improvements, net	[1]	162,357,260	172,309,537
TOTAL ASSETS	[2]	166,648,955	175,689,722
Residential Properties [Member] | Operating Segments [Member]
Segment Reporting Asset Reconciling Item [Line Items]
Land, buildings and improvements, net	[1]	38,280,020	34,813,680
TOTAL ASSETS	[2]	39,265,806	35,960,179
Retail/Mixed Use Properties [Member] | Operating Segments [Member]
Segment Reporting Asset Reconciling Item [Line Items]
Land, buildings and improvements, net	[1]	31,893,613	33,398,992
TOTAL ASSETS	[2]	$ 32,680,626	$ 35,320,092

[1] Includes lease intangibles and the land purchase option related to property acquisitions.

[2] Includes land, buildings and improvements, current receivables, deferred rent receivables and deferred leasing costs and other related intangible assets, all shown on a net basis.