Debt Financing Debt Financing (Details) - USD ($)		Sep. 30, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Available for Sale Securities at Par Value		$ 118,010,775	$ 118,342,000
TEB Facility [Member]
Debt Instrument [Line Items]
Available for Sale Securities at Par Value		102,866,709	103,516,998
TEB Facility [Member] | Ashley Square [Member] | Mortgage revenue bonds [Member]
Debt Instrument [Line Items]
Available for Sale Securities at Par Value		5,114,000	5,159,000
TEB Facility [Member] | Bella Vista [Member] | Mortgage revenue bonds [Member]
Debt Instrument [Line Items]
Available for Sale Securities at Par Value		6,430,000	6,490,000
TEB Facility [Member] | Bent Tree [Member] | Consolidated VIEs [Member]
Debt Instrument [Line Items]
Available for Sale Securities at Par Value		7,402,000	7,465,000
TEB Facility [Member] | Bridle Ridge [Member] | Mortgage revenue bonds [Member]
Debt Instrument [Line Items]
Available for Sale Securities at Par Value		7,595,000	7,655,000
TEB Facility [Member] | Brookstone [Member] | Mortgage revenue bonds [Member]
Debt Instrument [Line Items]
Available for Sale Securities at Par Value		9,191,008	9,256,001
TEB Facility [Member] | Cross Creek [Member] | Mortgage revenue bonds [Member]
Debt Instrument [Line Items]
Available for Sale Securities at Par Value		8,363,701	8,422,997
TEB Facility [Member] | Fairmont Oaks [Member] | Consolidated VIEs [Member]
Debt Instrument [Line Items]
Available for Sale Securities at Par Value		7,194,000	7,266,000
TEB Facility [Member] | Lake Forest [Member] | Mortgage revenue bonds [Member]
Debt Instrument [Line Items]
Available for Sale Securities at Par Value		8,796,000	8,886,000
TEB Facility [Member] | Runnymede [Member] | Mortgage revenue bonds [Member]
Debt Instrument [Line Items]
Available for Sale Securities at Par Value		10,395,000	10,440,000
TEB Facility [Member] | Southpark [Member] | Mortgage revenue bonds [Member]
Debt Instrument [Line Items]
Available for Sale Securities at Par Value		13,680,000	13,680,000
TEB Facility [Member] | Woodlynn Village [Member] | Mortgage revenue bonds [Member]
Debt Instrument [Line Items]
Available for Sale Securities at Par Value		4,371,000	4,390,000
TEB Facility [Member] | Series A [Member] | Ohio Properties [Member] | Mortgage revenue bonds [Member]
Debt Instrument [Line Items]
Available for Sale Securities at Par Value	[1]	$ 14,335,000	$ 14,407,000

[1] (1) Collateralized by Crescent Village, Postwoods, and Willow Bend