Debt Financing - Summary Of Gross Principal and Term A/B Trust Financings (Details) - USD ($)	3 Months Ended
	Mar. 31, 2018	Dec. 31, 2017
Short Term Debt [Line Items]
Debt financing	$ 550,425,793	$ 558,328,347
Term A/B Trust [Member]
Short Term Debt [Line Items]
Debt financing	106,810,000
Term A/B Trust [Member] | San Vicente Series A [Member]
Short Term Debt [Line Items]
Debt financing	$ 3,150,000
Year Acquired	2017
Stated Maturities	2022-02
Fixed Interest Rate	3.89%
Term A/B Trust [Member] | San Vicente Series B [Member]
Short Term Debt [Line Items]
Debt financing	$ 1,555,000
Year Acquired	2017
Stated Maturities	2018-06
Fixed Interest Rate	3.76%
Term A/B Trust [Member] | Las Palmas Series A [Member]
Short Term Debt [Line Items]
Debt financing	$ 1,530,000
Year Acquired	2017
Stated Maturities	2022-02
Fixed Interest Rate	3.89%
Term A/B Trust [Member] | Las Palmas Series B [Member]
Short Term Debt [Line Items]
Debt financing	$ 1,505,000
Year Acquired	2017
Stated Maturities	2018-06
Fixed Interest Rate	3.76%
Term A/B Trust [Member] | The Village At Madera Series A [Member]
Short Term Debt [Line Items]
Debt financing	$ 2,780,000
Year Acquired	2017
Stated Maturities	2022-02
Fixed Interest Rate	3.89%
Term A/B Trust [Member] | The Village At Madera Series B [Member]
Short Term Debt [Line Items]
Debt financing	$ 1,465,000
Year Acquired	2017
Stated Maturities	2018-07
Fixed Interest Rate	3.76%
Term A/B Trust [Member] | Harmony Court Bakers field Series A [Member]
Short Term Debt [Line Items]
Debt financing	$ 3,360,000
Year Acquired	2017
Stated Maturities	2022-02
Fixed Interest Rate	3.89%
Term A/B Trust [Member] | Harmony Court Bakers field Series B [Member]
Short Term Debt [Line Items]
Debt financing	$ 1,700,000
Year Acquired	2017
Stated Maturities	2018-07
Fixed Interest Rate	3.76%
Term A/B Trust [Member] | Summerhill Series A [Member]
Short Term Debt [Line Items]
Debt financing	$ 5,785,000
Year Acquired	2017
Stated Maturities	2022-02
Fixed Interest Rate	3.89%
Term A/B Trust [Member] | Summerhill Series B [Member]
Short Term Debt [Line Items]
Debt financing	$ 2,870,000
Year Acquired	2017
Stated Maturities	2018-07
Fixed Interest Rate	3.76%
Term A/B Trust [Member] | Courtyard Series A [Member]
Short Term Debt [Line Items]
Debt financing	$ 9,210,000
Year Acquired	2017
Stated Maturities	2022-02
Fixed Interest Rate	3.89%
Term A/B Trust [Member] | Courtyard Series B [Member]
Short Term Debt [Line Items]
Debt financing	$ 5,295,000
Year Acquired	2017
Stated Maturities	2018-07
Fixed Interest Rate	3.76%
Term A/B Trust [Member] | Seasons Lakewood Series A [Member]
Short Term Debt [Line Items]
Debt financing	$ 6,615,000
Year Acquired	2017
Stated Maturities	2022-02
Fixed Interest Rate	3.89%
Term A/B Trust [Member] | Seasons Lakewood Series B [Member]
Short Term Debt [Line Items]
Debt financing	$ 4,475,000
Year Acquired	2017
Stated Maturities	2018-08
Fixed Interest Rate	3.76%
Term A/B Trust [Member] | Seasons San Juan Capistrano Series A [Member]
Short Term Debt [Line Items]
Debt financing	$ 11,140,000
Year Acquired	2017
Stated Maturities	2022-02
Fixed Interest Rate	3.89%
Term A/B Trust [Member] | Seasons San Juan Capistrano Series B [Member]
Short Term Debt [Line Items]
Debt financing	$ 5,590,000
Year Acquired	2017
Stated Maturities	2018-08
Fixed Interest Rate	3.76%
Term A/B Trust [Member] | Avistar at Wood Hollow - Series A [Member]
Short Term Debt [Line Items]
Debt financing	$ 27,075,000
Year Acquired	2017
Stated Maturities	2027-02
Fixed Interest Rate	4.46%
Term A/B Trust [Member] | Avistar at Wilcrest - Series A [Member]
Short Term Debt [Line Items]
Debt financing	$ 3,210,000
Year Acquired	2017
Stated Maturities	2027-02
Fixed Interest Rate	4.46%
Term A/B Trust [Member] | Avistar at Copperfield - Series A [Member]
Short Term Debt [Line Items]
Debt financing	$ 8,500,000
Year Acquired	2017
Stated Maturities	2027-02
Fixed Interest Rate	4.46%
Term A/B Trust [Member]
Short Term Debt [Line Items]
Debt financing	$ 28,290,000
Term A/B Trust [Member] | Oaks at Georgetown - Series A [Member]
Short Term Debt [Line Items]
Debt financing	$ 11,100,000
Year Acquired	2017
Stated Maturities	2022-03
Fixed Interest Rate	3.89%
Term A/B Trust [Member] | Oaks at Georgetown - Series B [Member]
Short Term Debt [Line Items]
Debt financing	$ 4,690,000
Year Acquired	2017
Stated Maturities	2018-08
Fixed Interest Rate	3.76%
Term A/B Trust [Member] | Harmony Terrace - Series A [Member]
Short Term Debt [Line Items]
Debt financing	$ 6,210,000
Year Acquired	2017
Stated Maturities	2022-03
Fixed Interest Rate	3.89%
Term A/B Trust [Member] | Harmony Terrace - Series B [Member]
Short Term Debt [Line Items]
Debt financing	$ 6,290,000
Year Acquired	2017
Stated Maturities	2018-08
Fixed Interest Rate	3.76%