Mortgage Revenue Bonds - Information Regarding MRBs Owned (Details) - USD ($)		Dec. 31, 2021	Dec. 31, 2020
Mortgage Revenue Bonds Held In Trust [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances		$ 639,116,502	$ 637,948,068
Cumulative Unrealized Gain		111,818,346	130,520,576
Estimated Fair Value		750,934,848	768,468,644
Mortgage Revenue Bonds Held In Trust [Member] | Courtyard [Member] | Series A [Member] | CA [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[1]	9,970,209	10,061,161
Cumulative Unrealized Gain	[1]	2,060,480	2,487,317
Estimated Fair Value	[1]	12,030,689	12,548,478
Mortgage Revenue Bonds Held In Trust [Member] | Arbors at Hickory Ridge [Member] | TN [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[2]	10,755,889	10,910,733
Cumulative Unrealized Gain	[2]	3,598,292	2,704,295
Estimated Fair Value	[2]	14,354,181	13,615,028
Mortgage Revenue Bonds Held In Trust [Member] | Harmony Court Bakersfield [Member] | Series A [Member] | CA [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[1]	3,635,277	3,668,439
Cumulative Unrealized Gain	[1]	720,308	889,216
Estimated Fair Value	[1]	4,355,585	4,557,655
Mortgage Revenue Bonds Held In Trust [Member] | Harmony Terrace [Member] | Series A [Member] | CA [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[1]	6,730,004	6,791,096
Cumulative Unrealized Gain	[1]	1,425,757	1,724,350
Estimated Fair Value	[1]	8,155,761	8,515,446
Mortgage Revenue Bonds Held In Trust [Member] | Avistar at the Crest [Member] | Series A [Member] | TX [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[2]	9,022,172	9,140,656
Cumulative Unrealized Gain	[2]	1,926,825	2,376,580
Estimated Fair Value	[2]	10,948,997	11,517,236
Mortgage Revenue Bonds Held In Trust [Member] | Avistar at the Oaks [Member] | Series A [Member] | TX [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[2]	7,295,334	7,388,262
Cumulative Unrealized Gain	[2]	1,578,333	1,854,785
Estimated Fair Value	[2]	8,873,667	9,243,047
Mortgage Revenue Bonds Held In Trust [Member] | Las Palmas II [Member] | Series A [Member] | CA [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[1]	1,649,370	1,664,566
Cumulative Unrealized Gain	[1]	332,704	400,431
Estimated Fair Value	[1]	1,982,074	2,064,997
Mortgage Revenue Bonds Held In Trust [Member] | Seasons at Simi Valley [Member] | Series A [Member] | CA [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[1]	4,188,582	4,236,876
Cumulative Unrealized Gain	[1]	1,011,623	1,180,122
Estimated Fair Value	[1]	5,200,205	5,416,998
Mortgage Revenue Bonds Held In Trust [Member] | Avistar at the Parkway [Member] | Series A [Member] | TX [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[3]	12,579,783	12,721,014
Cumulative Unrealized Gain	[3]	2,353,247	2,790,208
Estimated Fair Value	[3]	14,933,030	15,511,222
Mortgage Revenue Bonds Held In Trust [Member] | Sycamore Walk [Member] | Series A [Member] | CA [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[1]	3,474,617	3,517,919
Cumulative Unrealized Gain	[1]	696,090	888,485
Estimated Fair Value	[1]	4,170,707	4,406,404
Mortgage Revenue Bonds Held In Trust [Member] | Avistar in 09 [Member] | Series A [Member] | TX [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[2]	6,299,237	6,379,479
Cumulative Unrealized Gain	[2]	1,288,060	1,601,535
Estimated Fair Value	[2]	7,587,297	7,981,014
Mortgage Revenue Bonds Held In Trust [Member] | Montecito at Williams Ranch Apartments [Member] | Series A [Member] | CA [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[4]	7,568,334	7,626,287
Cumulative Unrealized Gain	[4]	1,983,454	2,350,276
Estimated Fair Value	[4]	9,551,788	9,976,563
Mortgage Revenue Bonds Held In Trust [Member] | Avistar on the Boulevard [Member] | Series A [Member] | TX [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[2]	15,370,243	15,572,093
Cumulative Unrealized Gain	[2]	3,165,575	3,779,139
Estimated Fair Value	[2]	18,535,818	19,351,232
Mortgage Revenue Bonds Held In Trust [Member] | Montevista [Member] | Series A [Member] | CA [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[4]	6,701,776	6,720,000
Cumulative Unrealized Gain	[4]	2,114,978	2,404,771
Estimated Fair Value	[4]	8,816,754	9,124,771
Mortgage Revenue Bonds Held In Trust [Member] | San Vicente [Member] | Series A [Member] | CA [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[1]	3,400,913	3,432,246
Cumulative Unrealized Gain	[1]	671,681	809,327
Estimated Fair Value	[1]	4,072,594	4,241,573
Mortgage Revenue Bonds Held In Trust [Member] | Avistar on the Hills [Member] | Series A [Member] | TX [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[2]	4,994,549	5,058,171
Cumulative Unrealized Gain	[2]	1,100,478	1,292,513
Estimated Fair Value	[2]	6,095,027	6,350,684
Mortgage Revenue Bonds Held In Trust [Member] | Ocotillo Springs [Member] | Series A [Member] | CA [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[4]	15,000,000	2,023,500
Cumulative Unrealized Gain	[4]	271,172	215,633
Estimated Fair Value	[4]	15,271,172	2,239,133
Mortgage Revenue Bonds Held In Trust [Member] | Residency at the Mayer [Member] | Series A [Member] | CA [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[4]	24,000,000
Estimated Fair Value	[4]	24,000,000
Mortgage Revenue Bonds Held In Trust [Member] | Bridle Ridge [Member] | SC [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[5]	7,145,000	7,235,000
Cumulative Unrealized Gain	[5]		153,657
Estimated Fair Value	[5]	7,145,000	7,388,657
Mortgage Revenue Bonds Held In Trust [Member] | Seasons Lakewood [Member] | Series A [Member] | CA [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[1]	7,168,917	7,233,993
Cumulative Unrealized Gain	[1]	1,518,742	1,836,808
Estimated Fair Value	[1]	8,687,659	9,070,801
Mortgage Revenue Bonds Held In Trust [Member] | Brookstone [Member] | IL [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[5]	7,334,161	7,374,252
Cumulative Unrealized Gain	[5]	1,903,086	2,201,663
Estimated Fair Value	[5]	9,237,247	9,575,915
Mortgage Revenue Bonds Held In Trust [Member] | Seasons San Juan Capistrano [Member] | Series A [Member] | CA [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[1]	12,070,116	12,179,682
Cumulative Unrealized Gain	[1]	2,557,065	2,973,846
Estimated Fair Value	[1]	14,627,181	15,153,528
Mortgage Revenue Bonds Held In Trust [Member] | Bruton Apartments [Member] | TX [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[1]	17,532,185	17,674,167
Cumulative Unrealized Gain	[1]	4,452,765	3,792,253
Estimated Fair Value	[1]	21,984,950	21,466,420
Mortgage Revenue Bonds Held In Trust [Member] | Summerhill [Member] | Series A [Member] | CA [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[1]	6,259,888	6,316,993
Cumulative Unrealized Gain	[1]	1,187,464	1,470,689
Estimated Fair Value	[1]	7,447,352	7,787,682
Mortgage Revenue Bonds Held In Trust [Member] | Columbia Gardens [Member] | SC [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[1]	12,725,440	12,898,904
Cumulative Unrealized Gain	[1]	2,003,599	2,689,886
Estimated Fair Value	[1]	14,729,039	15,588,790
Mortgage Revenue Bonds Held In Trust [Member] | Concord at Gulfgate [Member] | Series A [Member] | TX [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[1]	18,606,719	18,796,773
Cumulative Unrealized Gain	[1]	4,211,979	4,888,537
Estimated Fair Value	[1]	22,818,698	23,685,310
Mortgage Revenue Bonds Held In Trust [Member] | The Village at Madera [Member] | Series A [Member] | CA [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[1]	3,006,656	3,034,084
Cumulative Unrealized Gain	[1]	621,367	735,450
Estimated Fair Value	[1]	3,628,023	3,769,534
Mortgage Revenue Bonds Held In Trust [Member] | Concord at Little York [Member] | Series A [Member] | TX [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[1]	13,034,887	13,168,029
Cumulative Unrealized Gain	[1]	3,055,517	3,543,909
Estimated Fair Value	[1]	16,090,404	16,711,938
Mortgage Revenue Bonds Held In Trust [Member] | Concord at Williamcrest [Member] | Series A [Member] | TX [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[1]	20,192,436	20,398,687
Cumulative Unrealized Gain	[1]	4,651,973	5,397,326
Estimated Fair Value	[1]	24,844,409	25,796,013
Mortgage Revenue Bonds Held In Trust [Member] | Vineyard Gardens | Series A [Member] | CA [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[4]	3,939,476	3,969,173
Cumulative Unrealized Gain	[4]	987,782	1,226,058
Estimated Fair Value	[4]	4,927,258	5,195,231
Mortgage Revenue Bonds Held In Trust [Member] | Copper Gate Apartments [Member] | IN [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[2]	4,900,000	4,955,000
Cumulative Unrealized Gain	[2]	433,436	641,581
Estimated Fair Value	[2]	5,333,436	5,596,581
Mortgage Revenue Bonds Held In Trust [Member] | Cross Creek [Member] | SC [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[5]	6,120,285	6,136,261
Cumulative Unrealized Gain	[5]	1,845,064	2,277,289
Estimated Fair Value	[5]	7,965,349	8,413,550
Mortgage Revenue Bonds Held In Trust [Member] | Decatur-Angle [Member] | TX [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[1]	22,074,594	22,270,729
Cumulative Unrealized Gain	[1]	4,731,759	5,600,721
Estimated Fair Value	[1]	26,806,353	27,871,450
Mortgage Revenue Bonds Held In Trust [Member] | Glenview Apartments [Member] | Series A [Member] | CA [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[3]	4,429,350	4,483,154
Cumulative Unrealized Gain	[3]	863,955	1,010,425
Estimated Fair Value	[3]	5,293,305	5,493,579
Mortgage Revenue Bonds Held In Trust [Member] | Greens Property [Member] | Series A [Member] | NC [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[2]	7,719,000	7,829,000
Cumulative Unrealized Gain	[2]	281,953	663,781
Estimated Fair Value	[2]	8,000,953	8,492,781
Mortgage Revenue Bonds Held In Trust [Member] | Companion at Thornhill Apartments [Member] | SC [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[1]	10,924,609	11,055,254
Cumulative Unrealized Gain	[1]	1,793,226	2,208,446
Estimated Fair Value	[1]	12,717,835	13,263,700
Mortgage Revenue Bonds Held In Trust [Member] | Harden Ranch [Member] | Series A [Member] | CA [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[2]	6,538,111	6,621,823
Cumulative Unrealized Gain	[2]	1,285,747	1,606,690
Estimated Fair Value	[2]	7,823,858	8,228,513
Mortgage Revenue Bonds Held In Trust [Member] | Heritage Square [Member] | Series A [Member] | TX [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[3]	10,455,924	10,579,057
Cumulative Unrealized Gain	[3]	1,823,426	2,095,871
Estimated Fair Value	[3]	12,279,350	12,674,928
Mortgage Revenue Bonds Held In Trust [Member] | Live 929 Apartments [Member] | MD [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[4]		36,234,756
Estimated Fair Value	[4]		36,234,756
Mortgage Revenue Bonds Held In Trust [Member] | Live 929 Apartments [Member] | Series A [Member] | MD [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[4]	36,169,147
Cumulative Unrealized Gain	[4]	573,155
Estimated Fair Value	[4]	36,742,302
Mortgage Revenue Bonds Held In Trust [Member] | Jackson Manor Apartments [Member] | MS [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[4]	4,900,000
Estimated Fair Value	[4]	4,900,000
Mortgage Revenue Bonds Held In Trust [Member] | Gateway Village [Member] | NC [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[4]	2,600,000	2,600,000
Cumulative Unrealized Gain	[4]	90,861	136,612
Estimated Fair Value	[4]	2,690,861	2,736,612
Mortgage Revenue Bonds Held In Trust [Member] | Montclair Apartments [Member] | Series A [Member] | CA [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[3]	2,399,626	2,428,775
Cumulative Unrealized Gain	[3]	446,912	572,671
Estimated Fair Value	[3]	2,846,538	3,001,446
Mortgage Revenue Bonds Held In Trust [Member] | Lynnhaven Apartments [Member] | NC [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[4]	3,450,000	3,450,000
Cumulative Unrealized Gain	[4]	115,328	178,960
Estimated Fair Value	[4]	3,565,328	3,628,960
Mortgage Revenue Bonds Held In Trust [Member] | Ohio Properties [Member] | Series A [Member] | OH [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[5]	13,580,000	13,724,000
Cumulative Unrealized Gain	[5]		61,243
Estimated Fair Value	[5]	13,580,000	13,785,243
Mortgage Revenue Bonds Held In Trust [Member] | Renaissance [Member] | Series A [Member] | LA [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[3]	10,732,295	10,870,681
Cumulative Unrealized Gain	[3]	4,172,381	4,293,328
Estimated Fair Value	[3]	14,904,676	15,164,009
Mortgage Revenue Bonds Held In Trust [Member] | Village at Avalon [Member] | Series A [Member] | NM [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[6]	16,069,382	16,189,074
Cumulative Unrealized Gain	[6]	4,124,498	4,879,623
Estimated Fair Value	[6]	20,193,880	21,068,697
Mortgage Revenue Bonds Held In Trust [Member] | Runnymede [Member] | TX [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[5]	9,675,000	9,805,000
Cumulative Unrealized Gain	[5]	99,489	105,634
Estimated Fair Value	[5]	9,774,489	9,910,634
Mortgage Revenue Bonds Held In Trust [Member] | Santa Fe Apartments [Member] | Series A [Member] | CA [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[3]	2,907,057	2,942,370
Cumulative Unrealized Gain	[3]	567,028	724,678
Estimated Fair Value	[3]	3,474,085	3,667,048
Mortgage Revenue Bonds Held In Trust [Member] | Village at River's Edge [Member] | SC [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[1]	9,728,355	9,802,479
Cumulative Unrealized Gain	[1]	2,370,569	1,353,745
Estimated Fair Value	[1]	12,098,924	11,156,224
Mortgage Revenue Bonds Held In Trust [Member] | Silver Moon [Member] | Series A [Member] | NM [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[3]	7,629,704	7,697,891
Cumulative Unrealized Gain	[3]	1,868,323	1,995,694
Estimated Fair Value	[3]	9,498,027	9,693,585
Mortgage Revenue Bonds Held In Trust [Member] | Southpark [Member] | TX [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[5]	11,365,100	11,462,172
Cumulative Unrealized Gain	[5]	1,542,509	1,917,286
Estimated Fair Value	[5]	12,907,609	13,379,458
Mortgage Revenue Bonds Held In Trust [Member] | The Palms at Premier Park [Member] | SC [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[2]	18,385,572	18,619,081
Cumulative Unrealized Gain	[2]	2,181,632	2,906,879
Estimated Fair Value	[2]	20,567,204	21,525,960
Mortgage Revenue Bonds Held In Trust [Member] | Tyler Park Townhomes [Member] | Series A [Member] | CA [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[2]	5,694,168	5,767,938
Cumulative Unrealized Gain	[2]	691,137	939,214
Estimated Fair Value	[2]	6,385,305	6,707,152
Mortgage Revenue Bonds Held In Trust [Member] | Avistar at Copperfield [Member] | Series A [Member] | TX [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[4]	13,678,286	13,815,817
Cumulative Unrealized Gain	[4]	2,549,711	3,189,896
Estimated Fair Value	[4]	16,227,997	17,005,713
Mortgage Revenue Bonds Held In Trust [Member] | Rosewood Townhomes [Member] | Series A [Member] | SC [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[4]		9,259,206
Cumulative Unrealized Gain	[4]		578,247
Estimated Fair Value	[4]		9,837,453
Mortgage Revenue Bonds Held In Trust [Member] | Westside Village Market [Member] | Series A [Member] | CA [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[2]	3,721,129	3,769,337
Cumulative Unrealized Gain	[2]	701,915	859,860
Estimated Fair Value	[2]	4,423,044	4,629,197
Mortgage Revenue Bonds Held In Trust [Member] | South Pointe Apartments [Member] | Series A [Member] | SC [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[4]		21,551,600
Cumulative Unrealized Gain	[4]		1,345,919
Estimated Fair Value	[4]		22,897,519
Mortgage Revenue Bonds Held In Trust [Member] | Willow Run [Member] | SC [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[1]	12,549,146	12,720,560
Cumulative Unrealized Gain	[1]	1,974,479	2,650,995
Estimated Fair Value	[1]	14,523,625	15,371,555
Mortgage Revenue Bonds Held In Trust [Member] | Avistar at Wilcrest [Member] | Series A [Member] | TX [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[4]	5,183,794	5,235,915
Cumulative Unrealized Gain	[4]	772,242	1,084,347
Estimated Fair Value	[4]	5,956,036	6,320,262
Mortgage Revenue Bonds Held In Trust [Member] | Crossing at 1415 [Member] | Series A [Member] | TX [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[1]	7,253,698	7,331,821
Cumulative Unrealized Gain	[1]	1,549,224	1,810,458
Estimated Fair Value	[1]	8,802,922	9,142,279
Mortgage Revenue Bonds Held In Trust [Member] | Woodlynn Village [Member] | MN [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[5]		4,120,000
Cumulative Unrealized Gain	[5]		56,458
Estimated Fair Value	[5]		4,176,458
Mortgage Revenue Bonds Held In Trust [Member] | Avistar at Wood Hollow [Member] | Series A [Member] | TX [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[4]	39,360,426	39,756,184
Cumulative Unrealized Gain	[4]	7,200,790	8,703,609
Estimated Fair Value	[4]	46,561,216	48,459,793
Mortgage Revenue Bonds Held In Trust [Member] | Heights at 515 [Member] | Series A [Member] | TX [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[1]	6,640,885	6,712,409
Cumulative Unrealized Gain	[1]	1,418,341	1,600,836
Estimated Fair Value	[1]	8,059,226	8,313,245
Mortgage Revenue Bonds Held In Trust [Member] | 15 West Apartments [Member] | WA [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[1]	9,531,842	9,604,680
Cumulative Unrealized Gain	[1]	2,799,259	3,257,826
Estimated Fair Value	[1]	12,331,101	12,862,506
Mortgage Revenue Bonds Held In Trust [Member] | Esperanza at Palo Alto [Member] | TX [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[1]	19,071,622	19,218,417
Cumulative Unrealized Gain	[1]	5,317,911	5,955,488
Estimated Fair Value	[1]	24,389,533	25,173,905
Mortgage Revenue Bonds Held In Trust [Member] | Oaks at Georgetown [Member] | Series A [Member] | TX [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances	[1]	12,026,225	12,135,392
Cumulative Unrealized Gain	[1]	2,181,690	2,597,201
Estimated Fair Value	[1]	14,207,915	14,732,593
Mortgage Revenue Bonds [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances		41,395,781	24,472,905
Cumulative Unrealized Gain		1,179,215	1,490,936
Estimated Fair Value		42,574,996	25,963,841
Mortgage Revenue Bonds [Member] | Avistar at the Crest [Member] | Series B [Member] | TX [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances		730,612	735,974
Cumulative Unrealized Gain		122,646	144,746
Estimated Fair Value		853,258	880,720
Mortgage Revenue Bonds [Member] | Avistar at the Oaks [Member] | Series B [Member] | TX [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances		534,953	538,723
Cumulative Unrealized Gain		86,437	100,668
Estimated Fair Value		621,390	639,391
Mortgage Revenue Bonds [Member] | Avistar at the Parkway [Member] | Series B [Member] | TX [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances		123,598	123,973
Cumulative Unrealized Gain		37,590	43,650
Estimated Fair Value		161,188	167,623
Mortgage Revenue Bonds [Member] | Avistar in 09 [Member] | Series B [Member] | TX [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances		441,288	444,398
Cumulative Unrealized Gain		71,303	83,042
Estimated Fair Value		512,591	527,440
Mortgage Revenue Bonds [Member] | Avistar on the Boulevard [Member] | Series B [Member] | TX [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances		434,132	437,318
Cumulative Unrealized Gain		69,950	82,718
Estimated Fair Value		504,082	520,036
Mortgage Revenue Bonds [Member] | Greens Property [Member] | Series B [Member] | NC [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances		920,637	925,607
Cumulative Unrealized Gain		46,672	107,347
Estimated Fair Value		967,309	1,032,954
Mortgage Revenue Bonds [Member] | Live 929 Apartments [Member] | Series B [Member] | MD [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances		17,344,000
Estimated Fair Value		17,344,000
Mortgage Revenue Bonds [Member] | Ohio Properties [Member] | Series B [Member] | OH [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances		3,465,270	3,485,690
Cumulative Unrealized Gain			13,578
Estimated Fair Value		3,465,270	3,499,268
Mortgage Revenue Bonds [Member] | Rosewood Townhomes [Member] | Series B [Member] | SC [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances			469,781
Cumulative Unrealized Gain			2,549
Estimated Fair Value			472,330
Mortgage Revenue Bonds [Member] | South Pointe Apartments [Member] | Series B [Member] | SC [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances			1,099,487
Cumulative Unrealized Gain			5,967
Estimated Fair Value			1,105,454
Mortgage Revenue Bonds [Member] | Lutheran Gardens [Member] | Series A [Member] | CA [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances		10,352,000
Estimated Fair Value		10,352,000
Mortgage Revenue Bonds [Member] | Meadow Valley [Member] | Series A [Member] | MI [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances		100,000
Estimated Fair Value		100,000
Mortgage Revenue Bonds [Member] | Solano Vista [Member] | Series A [Member] | CA [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances		2,649,291	2,665,000
Cumulative Unrealized Gain		744,617	891,612
Estimated Fair Value		3,393,908	3,556,612
Mortgage Revenue Bonds [Member] | Arby Road Apartments [Member] | Series A [Member] | NV [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances			7,385,000
Cumulative Unrealized Gain			15,059
Estimated Fair Value			7,400,059
Mortgage Revenue Bonds [Member] | Provision Center 2014-1 [Member] | TN [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost Adjusted for Paydowns and Allowances		4,300,000	6,161,954
Estimated Fair Value		$ 4,300,000	$ 6,161,954

[1] MRB owned by ATAX TEBS IV, LLC (M45 TEBS), Note 16

[2] MRB owned by ATAX TEBS II, LLC (M31 TEBS), Note 16

[3] MRB owned by ATAX TEBS III, LLC (M33 TEBS), Note 16

[4] MRB held by Mizuho Capital Markets, LLC in a debt financing transaction, Note 16

[5] MRB owned by ATAX TEBS I, LLC (M24 TEBS), Note 16

[6] MRB held by Morgan Stanley in a debt financing transaction, Note 16