Segment Reporting Segment Reporting (Details) (USD $)	3 Months Ended								12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Revenues [Abstract]
Revenues	$ 7,579,754	$ 6,312,905	$ 5,855,843	$ 5,371,149	$ 5,771,883	$ 5,660,808	$ 5,377,202	$ 4,888,902	$ 25,119,651	$ 21,698,795	$ 16,878,998
Interest Expense [Abstract]
Interest expense									5,530,995	5,441,700	1,887,823
Depreciation [Abstract]
Depreciation									4,029,711	3,135,155	2,727,392
Income (Loss) from Continuing Operations, Including Portion Attributable to Noncontrolling Interest [Abstract]
Income (Loss) from Continuing Operations before Income Taxes, Extraordinary Items, Noncontrolling Interest									2,763,762	(2,425,355)	(134,673)
Net Income (Loss) Attributable to Parent [Abstract]
Operating Income (Loss)	1,298,797	2,211,567	306,048	630,432	(3,321,900)	132,052	(243,248)	1,189,174	4,446,844	(2,243,922)	(400,360)
Assets [Abstract]
Assets	413,150,755				297,976,545				413,150,755	297,976,545	241,607,249
Partners' Capital
Partners' Capital	181,917,192				131,044,260				181,917,192	131,044,260	128,162,891
Tax-exempt bond investments [Member]
Revenues [Abstract]
Revenues									12,169,336	12,635,513	11,147,091
Interest Expense [Abstract]
Interest expense									3,510,182	4,463,926	1,755,427
Depreciation [Abstract]
Depreciation									0	0	0
Income (Loss) from Continuing Operations, Including Portion Attributable to Noncontrolling Interest [Abstract]
Income (Loss) from Continuing Operations before Income Taxes, Extraordinary Items, Noncontrolling Interest									4,136,126	(353,323)	2,384,926
Net Income (Loss) Attributable to Parent [Abstract]
Operating Income (Loss)									4,136,126	(353,323)	2,384,926
Assets [Abstract]
Assets	357,606,420				321,433,013				357,606,420	321,433,013	316,922,744
Partners' Capital
Partners' Capital	221,665,286				179,285,257				221,665,286	179,285,257	192,682,394
MF Properties [Member]
Revenues [Abstract]
Revenues									7,846,813	5,066,443	1,619,229
Interest Expense [Abstract]
Interest expense									1,439,370	977,774	132,396
Depreciation [Abstract]
Depreciation									2,485,365	1,451,875	501,053
Income (Loss) from Continuing Operations, Including Portion Attributable to Noncontrolling Interest [Abstract]
Income (Loss) from Continuing Operations before Income Taxes, Extraordinary Items, Noncontrolling Interest									(1,065,819)	(782,493)	(53,339)
Net Income (Loss) Attributable to Parent [Abstract]
Operating Income (Loss)									617,263	(601,060)	(319,026)
Assets [Abstract]
Assets	51,379,479				43,926,832				51,379,479	43,926,832	10,264,644
Partners' Capital
Partners' Capital	6,643,315				2,394,991				6,643,315	2,394,991	(3,882,221)
Public Housing Capital Fund Trust Certificates [Member]
Revenues [Abstract]
Revenues									1,624,534	0	0
Interest Expense [Abstract]
Interest expense									542,479	0	0
Depreciation [Abstract]
Depreciation									0	0	0
Income (Loss) from Continuing Operations, Including Portion Attributable to Noncontrolling Interest [Abstract]
Income (Loss) from Continuing Operations before Income Taxes, Extraordinary Items, Noncontrolling Interest									1,067,749	0	0
Net Income (Loss) Attributable to Parent [Abstract]
Operating Income (Loss)									1,067,749	0	0
Assets [Abstract]
Assets	65,811,361				0				65,811,361	0	0
Partners' Capital
Partners' Capital	16,720,915				0				16,720,915	0	0
Consolidated VIEs [Member]
Revenues [Abstract]
Revenues									4,805,746	10,043,284	7,487,438
Interest Expense [Abstract]
Interest expense									3,240,306	4,037,725	5,546,229
Depreciation [Abstract]
Depreciation									1,544,346	1,683,280	2,226,339
Income (Loss) from Continuing Operations, Including Portion Attributable to Noncontrolling Interest [Abstract]
Income (Loss) from Continuing Operations before Income Taxes, Extraordinary Items, Noncontrolling Interest									(3,285,896)	682,243	(8,230,629)
Net Income (Loss) Attributable to Parent [Abstract]
Operating Income (Loss)									(3,285,896)	682,243	(8,230,629)
Assets [Abstract]
Assets	30,207,191				24,315,353				30,207,191	24,315,353	47,504,227
Partners' Capital
Partners' Capital	(22,480,214)				(24,872,428)				(22,480,214)	(24,872,428)	(41,635,836)
Consolidation, Eliminations [Member]
Revenues [Abstract]
Revenues									(1,520,817)	(6,046,445)	(3,374,760)
Interest Expense [Abstract]
Interest expense									(3,240,306)	(4,037,725)	(5,546,229)
Depreciation [Abstract]
Depreciation									0	0	0
Income (Loss) from Continuing Operations, Including Portion Attributable to Noncontrolling Interest [Abstract]
Income (Loss) from Continuing Operations before Income Taxes, Extraordinary Items, Noncontrolling Interest									1,763,050	(1,971,782)	5,764,369
Net Income (Loss) Attributable to Parent [Abstract]
Operating Income (Loss)									1,763,050	(1,971,782)	5,764,369
Assets [Abstract]
Assets	(156,922,486)				(129,193,353)				(156,922,486)	(129,193,353)	(166,799,252)
Partners' Capital
Partners' Capital	(47,966,509)				(25,763,560)				(47,966,509)	(25,763,560)	(19,001,446)
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Revenues [Abstract]
Revenues									194,039	0	0
Interest Expense [Abstract]
Interest expense									38,964	0	0
Depreciation [Abstract]
Depreciation									0	0	0
Income (Loss) from Continuing Operations, Including Portion Attributable to Noncontrolling Interest [Abstract]
Income (Loss) from Continuing Operations before Income Taxes, Extraordinary Items, Noncontrolling Interest									148,552	0	0
Net Income (Loss) Attributable to Parent [Abstract]
Operating Income (Loss)									148,552	0	0
Assets [Abstract]
Assets	32,488,363				0				32,488,363	0	0
Partners' Capital
Partners' Capital	7,334,399				0				7,334,399	0	0
Segment, Discontinued Operations [Member]
Assets [Abstract]
Assets	$ 32,580,427				$ 37,494,700				$ 32,580,427	$ 37,494,700	$ 33,714,886