Interest Rate Derivative Agreements - Summary of Terms of Interest Rate Swaps (Details) - USD ($)	3 Months Ended	12 Months Ended
Mar. 31, 2018	Dec. 31, 2017
Derivative [Line Items]
Fair Value of Liability	$ (341,740)	$ (826,852)
Interest Rate Swaps [Member]
Derivative [Line Items]
Fair Value of Liability	$ (341,740)	$ (826,852)
Interest Rate Swaps [Member] \| Deutsche Bank [Member] \| Decatur-Angle Apartments [Member]
Derivative [Line Items]
Purchase Date	2014-09	2014-09
Notional Amount	$ 22,781,556	$ 22,821,429
Effective Date	2016-10	2016-10
Termination Date	2021-10	2021-10
Fixed Rate Paid	1.96%	1.96%
Period End Variable Rate Received	1.31%	1.08%
Fair Value of Liability	$ (146,935)	$ (402,261)
Interest Rate Swaps [Member] \| Deutsche Bank [Member] \| Decatur-Angle Apartments [Member] \| London Interbank Offered Rate [Member]
Derivative [Line Items]
Variable Based Rate	70.00%	70.00%
Interest Rate Swaps [Member] \| Deutsche Bank [Member] \| Bruton Apts [Member]
Derivative [Line Items]
Purchase Date	2014-09	2014-09
Notional Amount	$ 18,022,873	$ 18,051,775
Effective Date	2017-04	2017-04
Termination Date	2022-04	2022-04
Fixed Rate Paid	2.06%	2.06%
Period End Variable Rate Received	1.30%	1.08%
Fair Value of Liability	$ (194,805)	$ (424,591)
Interest Rate Swaps [Member] \| Deutsche Bank [Member] \| Bruton Apts [Member] \| London Interbank Offered Rate [Member]
Derivative [Line Items]
Variable Based Rate	70.00%	70.00%

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- Definition

Derivative period end variable rate received.

+ References

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- Definition

Derivative purchase month and year.

+ References

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+ References

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- Definition

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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- Definition

Fixed interest rate related to the interest rate derivative.

+ References

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- Definition

Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=82849420&loc=SL20226008-175313

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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