- Real Estate Assets and Accumulated Depreciation (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2018
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances				$ 693,501,574
Initial Cost of Company
Land				105,703,646
Buildings and Improvements				917,700,902
Total				1,023,404,548
Cost Capitalized Subsequent to Acquisition				46,695,484
Gross Amount at which Carried at Close of Period
Land				105,754,646
Buildings and Improvements				945,129,008
Total	$ 1,248,296,985	$ 1,694,278,958	$ 1,666,901,082	1,050,883,654
Accumulated Depreciation and Amortization				$ (203,993,817)
Real Estate [Roll Forward]
Balance at the beginning of the year	1,248,296,985	1,694,278,958	1,666,901,082
Acquisitions	135,486,062	0	0
Improvements	9,906,890	15,621,609	28,485,659
Cost of real estate sold	(341,007,619)	(461,332,750)	0
Write-off of disposed and fully depreciated and fully amortized assets	(1,798,664)	(270,832)	(1,107,783)
Balance at the end of the year	1,050,883,654	1,248,296,985	1,694,278,958
Accumulated Depreciation [Roll Forward]
Balance at the beginning of the year	221,581,654	232,744,083	163,445,987
Depreciation and amortization expense	46,109,794	67,755,152	69,513,484
Write-off of accumulated depreciation and amortization of real estate assets sold	(63,671,739)	(78,793,834)	0
Write-off of disposed and fully depreciated and fully amortized assets	(25,892)	(123,747)	(215,388)
Balance at the end of the year	203,993,817	$ 221,581,654	$ 232,744,083
Clarion Park Apartments [Member]
Real Estate and Accumulated Depreciation [Line Items]
Ownership Percent				100.00%
Encumbrances				$ 11,930,339
Initial Cost of Company
Land				1,470,991
Buildings and Improvements				9,744,009
Total				11,215,000
Cost Capitalized Subsequent to Acquisition				988,626
Gross Amount at which Carried at Close of Period
Land				1,470,991
Buildings and Improvements				10,450,720
Total	11,921,711			11,921,711
Accumulated Depreciation and Amortization				$ (3,224,329)
Real Estate [Roll Forward]
Balance at the end of the year	11,921,711
Truman Farm Villas Property [Member]
Real Estate and Accumulated Depreciation [Line Items]
Ownership Percent				100.00%
Encumbrances				$ 0
Initial Cost of Company
Land				842,987
Buildings and Improvements				8,257,013
Total				9,100,000
Cost Capitalized Subsequent to Acquisition				1,232,186
Gross Amount at which Carried at Close of Period
Land				842,987
Buildings and Improvements				9,248,570
Total	10,091,557			10,091,557
Accumulated Depreciation and Amortization				$ (2,953,604)
Real Estate [Roll Forward]
Balance at the end of the year	10,091,557
EBT Lofts [Member]
Real Estate and Accumulated Depreciation [Line Items]
Ownership Percent				100.00%
Encumbrances				$ 0
Initial Cost of Company
Land				460,362
Buildings and Improvements				8,114,638
Total				8,575,000
Cost Capitalized Subsequent to Acquisition				770,709
Gross Amount at which Carried at Close of Period
Land				460,362
Buildings and Improvements				8,543,029
Total	9,003,391			9,003,391
Accumulated Depreciation and Amortization				$ (2,561,371)
Real Estate [Roll Forward]
Balance at the end of the year	9,003,391
Spring Creek of Edmond [Member]
Real Estate and Accumulated Depreciation [Line Items]
Ownership Percent				100.00%
Encumbrances				$ 17,113,376
Initial Cost of Company
Land				2,346,503
Buildings and Improvements				17,602,343
Total				19,948,846
Cost Capitalized Subsequent to Acquisition				1,187,564
Gross Amount at which Carried at Close of Period
Land				2,346,503
Buildings and Improvements				18,384,515
Total	20,731,018			20,731,018
Accumulated Depreciation and Amortization				$ (5,204,981)
Real Estate [Roll Forward]
Balance at the end of the year	20,731,018
Montclair Parc Apartments [Member]
Real Estate and Accumulated Depreciation [Line Items]
Ownership Percent				100.00%
Encumbrances				$ 21,719,269
Initial Cost of Company
Land				3,325,556
Buildings and Improvements				32,424,444
Total				35,750,000
Cost Capitalized Subsequent to Acquisition				2,104,988
Gross Amount at which Carried at Close of Period
Land				3,325,556
Buildings and Improvements				33,343,837
Total	36,669,393			36,669,393
Accumulated Depreciation and Amortization				$ (8,840,527)
Real Estate [Roll Forward]
Balance at the end of the year	36,669,393
Sonoma Grande Apartments [Member]
Real Estate and Accumulated Depreciation [Line Items]
Ownership Percent				100.00%
Encumbrances				$ 20,451,101
Initial Cost of Company
Land				2,737,794
Buildings and Improvements				29,462,206
Total				32,200,000
Cost Capitalized Subsequent to Acquisition				1,166,391
Gross Amount at which Carried at Close of Period
Land				2,737,794
Buildings and Improvements				30,078,984
Total	32,816,778			32,816,778
Accumulated Depreciation and Amortization				$ (8,015,610)
Real Estate [Roll Forward]
Balance at the end of the year	32,816,778
Estancia Property [Member]
Real Estate and Accumulated Depreciation [Line Items]
Ownership Percent				100.00%
Encumbrances				$ 0
Initial Cost of Company
Land				2,544,634
Buildings and Improvements				27,240,628
Total				29,785,262
Cost Capitalized Subsequent to Acquisition				1,005,697
Gross Amount at which Carried at Close of Period
Land				2,544,634
Buildings and Improvements				27,724,761
Total	30,269,395			30,269,395
Accumulated Depreciation and Amortization				$ (7,239,095)
Real Estate [Roll Forward]
Balance at the end of the year	30,269,395
Hilliard Park Apartments [Member]
Real Estate and Accumulated Depreciation [Line Items]
Ownership Percent				100.00%
Encumbrances				$ 12,390,229
Initial Cost of Company
Land				1,413,437
Buildings and Improvements				18,484,692
Total				19,898,129
Cost Capitalized Subsequent to Acquisition				1,037,955
Gross Amount at which Carried at Close of Period
Land				1,413,437
Buildings and Improvements				19,117,326
Total	20,530,763			20,530,763
Accumulated Depreciation and Amortization				$ (4,837,983)
Real Estate [Roll Forward]
Balance at the end of the year	20,530,763
Sycamore Terrace Apartments [Member]
Real Estate and Accumulated Depreciation [Line Items]
Ownership Percent				100.00%
Encumbrances				$ 17,847,045
Initial Cost of Company
Land				1,321,194
Buildings and Improvements				21,852,963
Total				23,174,157
Cost Capitalized Subsequent to Acquisition				471,708
Gross Amount at which Carried at Close of Period
Land				1,321,194
Buildings and Improvements				21,879,086
Total	23,200,280			23,200,280
Accumulated Depreciation and Amortization				$ (5,253,317)
Real Estate [Roll Forward]
Balance at the end of the year	23,200,280
Hilliard Summit Apartments [Member]
Real Estate and Accumulated Depreciation [Line Items]
Ownership Percent				100.00%
Encumbrances				$ 15,027,104
Initial Cost of Company
Land				1,536,795
Buildings and Improvements				22,639,028
Total				24,175,823
Cost Capitalized Subsequent to Acquisition				572,011
Gross Amount at which Carried at Close of Period
Land				1,536,795
Buildings and Improvements				22,762,387
Total	24,299,182			24,299,182
Accumulated Depreciation and Amortization				$ (5,529,077)
Real Estate [Roll Forward]
Balance at the end of the year	24,299,182
Forty-57 Apartments [Member]
Real Estate and Accumulated Depreciation [Line Items]
Ownership Percent				100.00%
Encumbrances				$ 35,563,625
Initial Cost of Company
Land				3,055,614
Buildings and Improvements				49,444,386
Total				52,500,000
Cost Capitalized Subsequent to Acquisition				1,409,158
Gross Amount at which Carried at Close of Period
Land				3,055,614
Buildings and Improvements				50,091,659
Total	53,147,273			53,147,273
Accumulated Depreciation and Amortization				$ (12,032,326)
Real Estate [Roll Forward]
Balance at the end of the year	53,147,273
Riverford Crossing Apartments [Member]
Real Estate and Accumulated Depreciation [Line Items]
Ownership Percent				100.00%
Encumbrances				$ 20,229,093
Initial Cost of Company
Land				2,595,387
Buildings and Improvements				27,404,613
Total				30,000,000
Cost Capitalized Subsequent to Acquisition				911,816
Gross Amount at which Carried at Close of Period
Land				2,595,387
Buildings and Improvements				27,774,395
Total	30,369,782			30,369,782
Accumulated Depreciation and Amortization				$ (6,842,412)
Real Estate [Roll Forward]
Balance at the end of the year	30,369,782
Montecito Apartments [Member]
Real Estate and Accumulated Depreciation [Line Items]
Ownership Percent				100.00%
Encumbrances				$ 12,823,790
Initial Cost of Company
Land				3,081,522
Buildings and Improvements				15,918,478
Total				19,000,000
Cost Capitalized Subsequent to Acquisition				2,914,296
Gross Amount at which Carried at Close of Period
Land				3,081,522
Buildings and Improvements				18,398,578
Total	21,480,100			21,480,100
Accumulated Depreciation and Amortization				$ (5,151,505)
Real Estate [Roll Forward]
Balance at the end of the year	21,480,100
Hilliard Grand Apartments [Member]
Real Estate and Accumulated Depreciation [Line Items]
Ownership Percent				100.00%
Encumbrances				$ 28,392,107
Initial Cost of Company
Land				2,657,734
Buildings and Improvements				38,012,528
Total				40,670,262
Cost Capitalized Subsequent to Acquisition				701,519
Gross Amount at which Carried at Close of Period
Land				2,657,734
Buildings and Improvements				37,897,380
Total	40,555,114			40,555,114
Accumulated Depreciation and Amortization				$ (8,766,861)
Real Estate [Roll Forward]
Balance at the end of the year	40,555,114
Library Lofts East [Member]
Real Estate and Accumulated Depreciation [Line Items]
Ownership Percent				100.00%
Encumbrances				$ 8,166,247
Initial Cost of Company
Land				1,669,405
Buildings and Improvements				11,080,595
Total				12,750,000
Cost Capitalized Subsequent to Acquisition				540,378
Gross Amount at which Carried at Close of Period
Land				1,669,405
Buildings and Improvements				11,415,006
Total	13,084,411			13,084,411
Accumulated Depreciation and Amortization				$ (2,743,641)
Real Estate [Roll Forward]
Balance at the end of the year	13,084,411
Deep Deuce at Bricktown [Member]
Real Estate and Accumulated Depreciation [Line Items]
Ownership Percent				100.00%
Encumbrances				$ 32,069,379
Initial Cost of Company
Land				2,529,318
Buildings and Improvements				37,266,648
Total				39,795,966
Cost Capitalized Subsequent to Acquisition				6,197,411
Gross Amount at which Carried at Close of Period
Land				2,580,318
Buildings and Improvements				42,737,983
Total	45,318,301			45,318,301
Accumulated Depreciation and Amortization				$ (12,398,000)
Real Estate [Roll Forward]
Balance at the end of the year	45,318,301
Retreat at Quail North [Member]
Real Estate and Accumulated Depreciation [Line Items]
Ownership Percent				100.00%
Encumbrances				$ 16,268,147
Initial Cost of Company
Land				1,700,810
Buildings and Improvements				24,025,543
Total				25,726,353
Cost Capitalized Subsequent to Acquisition				556,897
Gross Amount at which Carried at Close of Period
Land				1,700,810
Buildings and Improvements				24,093,797
Total	25,794,607			25,794,607
Accumulated Depreciation and Amortization				$ (5,539,869)
Real Estate [Roll Forward]
Balance at the end of the year	25,794,607
Waterford on the Meadow [Member]
Real Estate and Accumulated Depreciation [Line Items]
Ownership Percent				100.00%
Encumbrances				$ 15,175,716
Initial Cost of Company
Land				2,625,024
Buildings and Improvements				20,849,131
Total				23,474,155
Cost Capitalized Subsequent to Acquisition				3,702,083
Gross Amount at which Carried at Close of Period
Land				2,625,024
Buildings and Improvements				23,986,048
Total	26,611,072			26,611,072
Accumulated Depreciation and Amortization				$ (6,140,697)
Real Estate [Roll Forward]
Balance at the end of the year	26,611,072
Tapestry Park Apartments [Member]
Real Estate and Accumulated Depreciation [Line Items]
Ownership Percent				100.00%
Encumbrances				$ 43,712,670
Initial Cost of Company
Land				3,277,884
Buildings and Improvements				47,118,797
Total				50,396,681
Cost Capitalized Subsequent to Acquisition				420,292
Gross Amount at which Carried at Close of Period
Land				3,277,884
Buildings and Improvements				46,900,625
Total	50,178,509			50,178,509
Accumulated Depreciation and Amortization				$ (10,572,417)
Real Estate [Roll Forward]
Balance at the end of the year	50,178,509
Dawntree Apartments [Member]
Real Estate and Accumulated Depreciation [Line Items]
Ownership Percent				100.00%
Encumbrances				$ 14,450,118
Initial Cost of Company
Land				3,135,425
Buildings and Improvements				21,753,469
Total				24,888,894
Cost Capitalized Subsequent to Acquisition				2,360,472
Gross Amount at which Carried at Close of Period
Land				3,135,425
Buildings and Improvements				23,511,480
Total	26,646,905			26,646,905
Accumulated Depreciation and Amortization				$ (5,864,112)
Real Estate [Roll Forward]
Balance at the end of the year	26,646,905
Stuart Hall Lofts [Member]
Real Estate and Accumulated Depreciation [Line Items]
Ownership Percent				100.00%
Encumbrances				$ 16,045,948
Initial Cost of Company
Land				1,585,035
Buildings and Improvements				15,264,965
Total				16,850,000
Cost Capitalized Subsequent to Acquisition				259,800
Gross Amount at which Carried at Close of Period
Land				1,585,035
Buildings and Improvements				15,240,006
Total	16,825,041			16,825,041
Accumulated Depreciation and Amortization				$ (3,363,616)
Real Estate [Roll Forward]
Balance at the end of the year	16,825,041
BriceGrove Park Apartments [Member]
Real Estate and Accumulated Depreciation [Line Items]
Ownership Percent				100.00%
Encumbrances				$ 17,133,615
Initial Cost of Company
Land				1,596,212
Buildings and Improvements				18,503,788
Total				20,100,000
Cost Capitalized Subsequent to Acquisition				868,554
Gross Amount at which Carried at Close of Period
Land				1,596,212
Buildings and Improvements				18,921,522
Total	20,517,734			20,517,734
Accumulated Depreciation and Amortization				$ (4,348,152)
Real Estate [Roll Forward]
Balance at the end of the year	20,517,734
Retreat at Hamburg Place [Member]
Real Estate and Accumulated Depreciation [Line Items]
Ownership Percent				100.00%
Encumbrances				$ 12,072,255
Initial Cost of Company
Land				1,605,839
Buildings and Improvements				14,694,161
Total				16,300,000
Cost Capitalized Subsequent to Acquisition				400,090
Gross Amount at which Carried at Close of Period
Land				1,605,839
Buildings and Improvements				14,766,336
Total	16,372,175			16,372,175
Accumulated Depreciation and Amortization				$ (3,359,740)
Real Estate [Roll Forward]
Balance at the end of the year	16,372,175
Villas at Huffmeister [Member]
Real Estate and Accumulated Depreciation [Line Items]
Ownership Percent				100.00%
Encumbrances				$ 27,058,201
Initial Cost of Company
Land				5,858,663
Buildings and Improvements				31,741,337
Total				37,600,000
Cost Capitalized Subsequent to Acquisition				1,943,132
Gross Amount at which Carried at Close of Period
Land				5,858,663
Buildings and Improvements				32,964,053
Total	38,822,716			38,822,716
Accumulated Depreciation and Amortization				$ (7,702,859)
Real Estate [Roll Forward]
Balance at the end of the year	38,822,716
Villas of Kingwood [Member]
Real Estate and Accumulated Depreciation [Line Items]
Ownership Percent				100.00%
Encumbrances				$ 35,156,654
Initial Cost of Company
Land				6,512,468
Buildings and Improvements				33,637,532
Total				40,150,000
Cost Capitalized Subsequent to Acquisition				2,333,431
Gross Amount at which Carried at Close of Period
Land				6,512,468
Buildings and Improvements				35,182,141
Total	41,694,609			41,694,609
Accumulated Depreciation and Amortization				$ (8,339,936)
Real Estate [Roll Forward]
Balance at the end of the year	41,694,609
Waterford Place at Riata Ranch [Member]
Real Estate and Accumulated Depreciation [Line Items]
Ownership Percent				100.00%
Encumbrances				$ 0
Initial Cost of Company
Land				3,184,857
Buildings and Improvements				20,215,143
Total				23,400,000
Cost Capitalized Subsequent to Acquisition				1,098,339
Gross Amount at which Carried at Close of Period
Land				3,184,857
Buildings and Improvements				20,813,492
Total	23,998,349			23,998,349
Accumulated Depreciation and Amortization				$ (4,944,919)
Real Estate [Roll Forward]
Balance at the end of the year	23,998,349
Carrington Place [Member]
Real Estate and Accumulated Depreciation [Line Items]
Ownership Percent				100.00%
Encumbrances				$ 27,384,768
Initial Cost of Company
Land				5,450,417
Buildings and Improvements				27,449,583
Total				32,900,000
Cost Capitalized Subsequent to Acquisition				1,937,311
Gross Amount at which Carried at Close of Period
Land				5,450,417
Buildings and Improvements				28,692,733
Total	34,143,150			34,143,150
Accumulated Depreciation and Amortization				$ (6,646,264)
Real Estate [Roll Forward]
Balance at the end of the year	34,143,150
Carrington at Champion Forest [Member]
Real Estate and Accumulated Depreciation [Line Items]
Ownership Percent				100.00%
Encumbrances				$ 24,978,692
Initial Cost of Company
Land				3,760,329
Buildings and Improvements				29,239,671
Total				33,000,000
Cost Capitalized Subsequent to Acquisition				1,496,724
Gross Amount at which Carried at Close of Period
Land				3,760,329
Buildings and Improvements				30,120,500
Total	33,880,829			33,880,829
Accumulated Depreciation and Amortization				$ (6,893,137)
Real Estate [Roll Forward]
Balance at the end of the year	33,880,829
Carrington Park at Huffmeister [Member]
Real Estate and Accumulated Depreciation [Line Items]
Ownership Percent				100.00%
Encumbrances				$ 19,440,839
Initial Cost of Company
Land				3,241,747
Buildings and Improvements				21,908,253
Total				25,150,000
Cost Capitalized Subsequent to Acquisition				1,205,865
Gross Amount at which Carried at Close of Period
Land				3,241,747
Buildings and Improvements				22,589,773
Total	25,831,520			25,831,520
Accumulated Depreciation and Amortization				$ (5,300,183)
Real Estate [Roll Forward]
Balance at the end of the year	25,831,520
Heritage Grand at Sienna Plantation [Member]
Real Estate and Accumulated Depreciation [Line Items]
Ownership Percent				100.00%
Encumbrances				$ 16,822,121
Initial Cost of Company
Land				3,776,547
Buildings and Improvements				22,762,411
Total				26,538,958
Cost Capitalized Subsequent to Acquisition				499,424
Gross Amount at which Carried at Close of Period
Land				3,776,547
Buildings and Improvements				22,715,694
Total	26,492,241			26,492,241
Accumulated Depreciation and Amortization				$ (4,979,819)
Real Estate [Roll Forward]
Balance at the end of the year	26,492,241
Mallard Crossing [Member]
Real Estate and Accumulated Depreciation [Line Items]
Ownership Percent				100.00%
Encumbrances				$ 33,367,682
Initial Cost of Company
Land				2,383,256
Buildings and Improvements				37,416,744
Total				39,800,000
Cost Capitalized Subsequent to Acquisition				1,866,149
Gross Amount at which Carried at Close of Period
Land				2,383,256
Buildings and Improvements				38,612,320
Total	40,995,576			40,995,576
Accumulated Depreciation and Amortization				$ (7,861,158)
Real Estate [Roll Forward]
Balance at the end of the year	40,995,576
Reserve At Creekside Village [Member]
Real Estate and Accumulated Depreciation [Line Items]
Ownership Percent				100.00%
Encumbrances				$ 14,241,494
Initial Cost of Company
Land				1,344,233
Buildings and Improvements				17,530,767
Total				18,875,000
Cost Capitalized Subsequent to Acquisition				1,242,125
Gross Amount at which Carried at Close of Period
Land				1,344,233
Buildings and Improvements				18,420,868
Total	19,765,101			19,765,101
Accumulated Depreciation and Amortization				$ (3,627,475)
Real Estate [Roll Forward]
Balance at the end of the year	19,765,101
Double Creek Flats Property [Member]
Real Estate and Accumulated Depreciation [Line Items]
Ownership Percent				100.00%
Encumbrances				$ 21,877,897
Initial Cost of Company
Land				1,306,880
Buildings and Improvements				30,545,199
Total				31,852,079
Cost Capitalized Subsequent to Acquisition				85,220
Gross Amount at which Carried at Close of Period
Land				1,306,880
Buildings and Improvements				30,166,508
Total	31,473,388			31,473,388
Accumulated Depreciation and Amortization				$ (866,844)
Real Estate [Roll Forward]
Balance at the end of the year	31,473,388
Jefferson at Perimeter Apartments [Member]
Real Estate and Accumulated Depreciation [Line Items]
Ownership Percent				100.00%
Encumbrances				$ 64,387,092
Initial Cost of Company
Land				17,763,296
Buildings and Improvements				85,870,687
Total				103,633,983
Cost Capitalized Subsequent to Acquisition				712,061
Gross Amount at which Carried at Close of Period
Land				17,763,296
Buildings and Improvements				85,279,756
Total	103,043,052			103,043,052
Accumulated Depreciation and Amortization				$ (1,876,207)
Real Estate [Roll Forward]
Balance at the end of the year	$ 103,043,052