Segments (Reconciliation to Net Income Loss) (Details) (USD $)	3 Months Ended	6 Months Ended
Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Segment Reporting Information [Line Items]
Revenues	$ 4,857,269	$ 4,273,140	$ 10,025,865	$ 8,361,326
Rental operating costs	1,510,787	1,331,904	3,007,389	2,665,035
Interest Income Mortgage Loans	14,738	18,333	29,314	36,523
Interest Income, Other	55,701	1,792	62,381	3,961
Gain on sale of real estate	410,258	54,993	856,911	99,075
General and administrative	1,350,968	1,071,552	2,583,729	2,196,270
Interest expense	1,219,329	1,071,686	2,553,355	2,053,170
Depreciation and amortization	1,325,534	1,214,150	2,640,738	2,390,888
Income (loss) attributable to noncontrolling interests	327,550	92,187	638,611	200,354
Net (loss) income	(396,202)	(433,221)	(449,351)	(1,004,832)
Industrial Office Properties [Member]
Segment Reporting Information [Line Items]
Revenues	2,634,708	2,129,857	5,210,357	4,149,268
Rental operating costs	806,970	716,548	1,657,430	1,398,057
Operating Income (Loss)	1,827,738	1,413,309	3,552,927	2,751,211
Residential Properties [Member]
Segment Reporting Information [Line Items]
Revenues	756,100	659,375	1,630,418	1,313,556
Rental operating costs	76,055	77,893	152,834	153,836
Operating Income (Loss)	680,045	581,482	1,477,584	1,159,720
Retail Properties [Member]
Segment Reporting Information [Line Items]
Revenues	644,498	740,288	1,640,372	1,440,644
Rental operating costs	203,009	184,610	387,304	390,373
Operating Income (Loss)	441,489	555,678	1,253,068	1,050,271
Self Storage Properties [Member]
Segment Reporting Information [Line Items]
Revenues	821,963	743,620	1,544,718	1,457,858
Rental operating costs	424,753	352,853	809,821	722,769
Operating Income (Loss)	397,210	390,767	734,897	735,089
Reportable Segment [Member]
Segment Reporting Information [Line Items]
Operating Income (Loss)	$ 3,361,220	$ 2,959,569	$ 7,047,790	$ 5,732,814

Interest income from mortgage loans.

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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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Costs incurred and are directly related to generating revenues from leased and rented property or equipment.

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The net gain (loss) resulting from the sale, transfer, termination, or other disposition of assets during the period, excluding transactions involving capital leases, assets-held- or available-for-lease, and other real estate owned which, to the extent appropriate, are included in gains (losses) on the disposition of assets in nonoperating income (expense).

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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 income (loss) from continuing operations attributable to the parent. Also defined as revenue less expenses and taxes from ongoing operations before extraordinary items but after deduction of those portions of income or loss from continuing operations that are allocable to noncontrolling interests.

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Amount of income (loss) from continuing operations attributable to the noncontrolling interest. Also defined as revenue less expenses and taxes from ongoing operations before extraordinary items but after deduction of those portions of income or loss from continuing operations that are allocable to noncontrolling interests.

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Represents the portion of interest incurred in the period on debt arrangements that was charged against earnings.

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Amount of interest income earned from interest bearing assets not separately disclosed.

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Aggregate revenue recognized during the period (derived from goods sold, services rendered, insurance premiums, or other activities that constitute an entity's earning process). For financial services companies, also includes investment and interest income, and sales and trading gains.

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