Investments in Unconsolidated Entities - Additional Information (Details) - USD ($)	1 Months Ended			9 Months Ended	12 Months Ended
	Jun. 30, 2020	Dec. 31, 2019	Sep. 30, 2019	Sep. 30, 2019	Dec. 31, 2020	Dec. 31, 2019	Nov. 30, 2020	Aug. 31, 2020	Jan. 31, 2020	Apr. 30, 2019
Schedule Of Equity Method Investments [Line Items]
Gain on sale of investments in unconsolidated entities						$ 16,141,797
Vantage At Westover Hills [Member]
Schedule Of Equity Method Investments [Line Items]
Equity commitment of fund construction									$ 7,300,000
Vantage At Waco [Member]
Schedule Of Equity Method Investments [Line Items]
Cash received	$ 10,800,000
Income on sale of properties	$ 1,500,000
Vantage At Tomball [Member]
Schedule Of Equity Method Investments [Line Items]
Equity commitment of fund construction								$ 10,400,000
Vantage At Hutto [Member]
Schedule Of Equity Method Investments [Line Items]
Equity commitment of fund construction							$ 10,500,000
Vantage At San Marcos [Member]
Schedule Of Equity Method Investments [Line Items]
Equity commitment of fund construction							$ 9,900,000
Vantage At Conroe [Member]
Schedule Of Equity Method Investments [Line Items]
Equity commitment of fund construction										$ 9,000,000.0
Vantage At Panama City Beach [Member]
Schedule Of Equity Method Investments [Line Items]
Cash received			$ 22,700,000
Income on sale of properties			10,500,000	$ 547,000
Vantage At Boerne [Member]
Schedule Of Equity Method Investments [Line Items]
Cash received		$ 15,200,000
Income on sale of properties		1,200,000
Gain on sale of investments in unconsolidated entities		$ 5,700,000
Maximum [Member] | Vantage At Panama City Beach [Member]
Schedule Of Equity Method Investments [Line Items]
Cash received			$ 325,000
ATAX Vantage Holdings, LLC [Member] | Minimum [Member]
Schedule Of Equity Method Investments [Line Items]
Return on investment period					2 years
ATAX Vantage Holdings, LLC [Member] | Maximum [Member]
Schedule Of Equity Method Investments [Line Items]
Return on investment period					3 years