Investment in Joint Venture (Components of Income from Discontinued Operations Recognized by Joint Ventures) (Details) (Fund VIII-IX Associates, USD $)	3 Months Ended	6 Months Ended
Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Fund VIII-IX Associates
Schedule of Equity Method Investments [Line Items]
Operating Income			$ 88,243	$ 160,405
Gain on Sale			2,026,403	0
Total	$ 1,348	$ 77,751	$ 2,114,646	$ 160,405

This item represents the amount of gain (loss) arising from the disposal of an equity method investment.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration