Segments (Net Operating Income by Segment) (Details) (USD $)	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Net Operating Income [Abstract]
Rental income	$ 5,382,600us-gaap_Revenues	$ 3,919,253us-gaap_Revenues
Property and related expenses	(1,939,589)	(1,260,562)
General and administrative expenses	(1,154,802)us-gaap_GeneralAndAdministrativeExpense	(1,124,856)us-gaap_GeneralAndAdministrativeExpense
Depreciation and amortization	(1,861,546)	(1,178,487)
Interest expense - mortgage notes	(1,432,163)us-gaap_InterestExpenseDebt	(1,049,082)us-gaap_InterestExpenseDebt
Interest and other income	14,604us-gaap_InterestIncomeOperating	18,369us-gaap_InterestIncomeOperating
Gain on sales of real estate and partnerships, net	78,496us-gaap_GainLossOnSaleOfBusiness	727,776us-gaap_GainLossOnSaleOfBusiness
Net income (loss)	(1,829,525)us-gaap_ProfitLoss	118,093us-gaap_ProfitLoss
Significant Reconciling Items [Member]
Net Operating Income [Abstract]
Net operating income, as defined	3,473,314	2,724,383
General and administrative expenses	(1,154,802)	(1,124,856)
Depreciation and amortization	(1,861,546)	(1,345,756)
Interest expense - mortgage notes	(2,379,592)	(1,049,082)
Interest and other income	14,604	18,369
Gain on sales of real estate and partnerships, net	78,496	727,776
Net income (loss)	(1,829,526)	(49,166)
Industrial Office Properties [Member] \| Significant Reconciling Items [Member]
Net Operating Income [Abstract]
Rental income	4,008,818	2,607,246
Property and related expenses	(1,580,965)	(1,039,090)
Net operating income, as defined	2,427,853	1,568,156
Residential Properties [Member] \| Significant Reconciling Items [Member]
Net Operating Income [Abstract]
Rental income	357,903	671,186
Property and related expenses	(11,238)	(6,735)
Net operating income, as defined	346,665	664,451
Retail Properties [Member] \| Significant Reconciling Items [Member]
Net Operating Income [Abstract]
Rental income	1,015,878	640,826
Property and related expenses	(347,385)	(214,732)
Net operating income, as defined	668,493	426,094
Self Storage Properties [Member] \| Significant Reconciling Items [Member]
Net Operating Income [Abstract]
Rental income	892,977	860,587
Property and related expenses	(862,674)	(794,905)
Net operating income, as defined	$ 30,303	$ 65,682

The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

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Amount of expense incurred and directly related to generating revenue from leased and rented property or equipment.

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Gain (loss) from sale or disposal of an organization or integrated set of activities (for example, but not limited to, a partnership or corporation) engaged in providing a product or service in a commercial, industrial, or professional environment.

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The aggregate total of expenses of managing and administering the affairs of an entity, including affiliates of the reporting entity, which are not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

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Amount of the cost of borrowed funds accounted for as interest expense for debt.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

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The net result for the period of deducting operating expenses from operating revenues.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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