Segments (Net Operating Income by Segment) (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Net Operating Income [Abstract]
Rental income	$ 19,902,410us-gaap_Revenues	$ 19,563,122us-gaap_Revenues
Property and related expenses	(7,465,658)	(6,382,425)
Asset impairment	(950,000)us-gaap_AssetImpairmentCharges	(2,000,000)us-gaap_AssetImpairmentCharges
General and administrative expenses	(5,555,449)us-gaap_GeneralAndAdministrativeExpense	(5,443,652)us-gaap_GeneralAndAdministrativeExpense
Depreciation and amortization	(6,049,385)	(5,309,560)
Interest expense debt	(6,478,976)us-gaap_InterestExpenseDebt	(5,059,912)us-gaap_InterestExpenseDebt
Interest income	85,806us-gaap_InterestIncomeOperating	116,602us-gaap_InterestIncomeOperating
Gain on sales of real estate and partnerships, net	5,120,699us-gaap_GainLossOnSaleOfBusiness	1,992,754us-gaap_GainLossOnSaleOfBusiness
Loss from continuing operations	(853,601)	(2,523,071)
Significant Reconciling Items [Member]
Net Operating Income [Abstract]
Net operating income, as defined	11,486,948	11,180,697
General and administrative expenses	(5,555,449)	(5,443,652)
Depreciation and amortization	(6,049,385)	(5,309,560)
Interest expense debt	(6,478,976)	(5,059,912)
Interest income	85,806	116,602
Gain on sales of real estate and partnerships, net	5,120,699	1,992,754
Gain on extinguishment of debt	536,952	0
Loss from continuing operations	(853,601)	(2,523,071)
Industrial Office Properties [Member]
Net Operating Income [Abstract]
Rental income	11,800,819	10,448,256
Property and related expenses	(4,769,364)	(3,629,413)
Asset impairment	(950,000)	(2,000,000)
Net operating income, as defined	6,081,455	4,818,843
Residential Properties [Member]
Net Operating Income [Abstract]
Rental income	2,065,327	2,995,612
Property and related expenses	(102,082)	(195,752)
Net operating income, as defined	1,963,245	2,799,860
Retail Properties [Member]
Net Operating Income [Abstract]
Rental income	2,607,744	2,878,145
Property and related expenses	(877,620)	(861,327)
Net operating income, as defined	1,730,124	2,016,818
Self Storage Properties [Member]
Net Operating Income [Abstract]
Rental income	3,428,503	3,241,109
Property and related expenses	(1,716,379)	(1,695,933)
Net operating income, as defined	$ 1,712,124	$ 1,545,176

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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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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.

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- Definition

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

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- Definition

The difference between the reacquisition price and the net carrying amount of the extinguished debt recognized currently as a component of income in the period of extinguishment, net of tax.

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

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 50

-Section 40

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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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This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses and taxes from ongoing operations before extraordinary items, and noncontrolling interest.

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

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-Topic 225

-SubTopic 10

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Amount of operating interest income, including, but not limited to, amortization and accretion of premiums and discounts on securities.

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1)

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