Fair Value Measurements Available for sale securities (Details) - USD ($)		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Total gains (losses) (realized/unrealized) [Abstract]
Available-for-sale Securities		$ (90,016,872)	$ (47,366,656)
Fair Value, Inputs, Level 3 [Member]
Schedule of Available-for-sale Securities [Line Items]
Assets at Fair Value, beginning balance		653,875,949	520,951,907	$ 347,486,446
Total gains (losses) (realized/unrealized) [Abstract]
Total gain (losses) included in earnings		138,782	(1,802,655)	(2,003,351)
Total gain (losses) included in other comprehensive (loss) income		(22,245,924)	9,547,826	68,810,375
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases		130,620,000	188,572,000	142,794,827
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sale of securities		(9,295,399)
Derivative at purchase price			562,088	1,382,900
Available-for-sale Securities			(41,580,919)	(30,464,798)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements		(10,195,920)	(22,374,298)	(7,054,492)
Assets at Fair Value, ending balance		742,897,488	653,875,949	520,951,907
Total amount of losses for the period included in earnings attributable to the change in unrealized losses relating to assets or liabilities held on December 31, 2014		17,618	(1,802,655)	(2,003,351)
Fair Value, Inputs, Level 3 [Member] | Interest rate derivatives [Member]
Schedule of Available-for-sale Securities [Line Items]
Assets at Fair Value, beginning balance	[1]		267,669	888,120
Liabilities at Fair value, beginning balance	[1]	(972,898)
Total gains (losses) (realized/unrealized) [Abstract]
Total gain (losses) included in earnings	[1]	17,618	(1,802,655)	(2,003,351)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sale of securities	[1]	(399)
Derivative at purchase price	[1]		562,088	1,382,900
Assets at Fair Value, ending balance	[1]			267,669
Liabilities at Fair value, ending balance	[1]	(955,679)	(972,898)
Total amount of losses for the period included in earnings attributable to the change in unrealized losses relating to assets or liabilities held on December 31, 2014	[1]	17,618	(1,802,655)	(2,003,351)
Fair Value, Inputs, Level 3 [Member] | Bond Purchase Commitment [Member]
Schedule of Available-for-sale Securities [Line Items]
Assets at Fair Value, beginning balance		5,634,360	5,780,413
Liabilities at Fair value, beginning balance				(4,852,177)
Total gains (losses) (realized/unrealized) [Abstract]
Total gain (losses) included in other comprehensive (loss) income		(3,234,911)	(146,053)	10,632,590
Assets at Fair Value, ending balance		2,399,449	5,634,360	5,780,413
Fair Value, Inputs, Level 3 [Member] | PHC Certificates [Member]
Schedule of Available-for-sale Securities [Line Items]
Assets at Fair Value, beginning balance		60,707,290	61,263,123	62,056,379
Total gains (losses) (realized/unrealized) [Abstract]
Total gain (losses) included in earnings		(54,605)
Total gain (losses) included in other comprehensive (loss) income		(1,480,497)	462,297	5,219,937
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements		(2,014,120)	(1,018,130)	(6,013,193)
Assets at Fair Value, ending balance		57,158,068	60,707,290	61,263,123
Fair Value, Inputs, Level 3 [Member] | Taxable Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Assets at Fair Value, beginning balance		4,824,060	4,616,565	4,075,953
Total gains (losses) (realized/unrealized) [Abstract]
Total gain (losses) included in other comprehensive (loss) income		(188,299)	(138,682)	685,612
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements		(551,162)		(145,000)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Settlements			346,177
Assets at Fair Value, ending balance		4,084,599	4,824,060	4,616,565
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Settlements			346,177
Fair Value, Inputs, Level 3 [Member] | Mortgage Revenue Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Assets at Fair Value, beginning balance	[2]	583,683,137	449,024,137	285,318,171
Total gains (losses) (realized/unrealized) [Abstract]
Total gain (losses) included in earnings	[2]	175,769
Total gain (losses) included in other comprehensive (loss) income	[2]	(17,342,217)	9,370,264	52,272,236
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	[2]	130,620,000	188,572,000	142,794,827
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sale of securities	[2]	(9,295,000)
Available-for-sale Securities	[2]		(41,580,919)	(30,464,798)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements	[2]	(7,630,638)	(21,702,345)	(896,299)
Assets at Fair Value, ending balance	[2]	$ 680,211,051	$ 583,683,137	$ 449,024,137

[1] Interest rate derivatives include derivative contracts reported in other assets as well as derivative swap liabilities.

[2] Mortgage revenue bonds includes both bonds held in trust as well as those held by the Partnership.