Debt - Summary of Mortgage Debt Nonrecourse to Company and Encumbers Multifamily Properties (Parenthetical) (Details) $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($)
Debt Instrument [Line Items]
Deferred financing costs, net of accumulated amortization	$ 2,154
Cornerstone \| Debt With Fixed Interest Rate
Debt Instrument [Line Items]
Interest Rate	4.09%
Fair value of debt assumed upon acquisition	$ 18,000
Debt instrument, payment terms	The assumed debt carries a 4.09% fixed rate, was originally issued in March 2013, and had a term of 120 months with an initial 24 months of interest only.
Blended pay rate	4.24%
13th month through 81st month
Debt Instrument [Line Items]
Mortgage loans payable description	Loan can be pre-paid in the first 12 months of the term at par plus 5.00%. Starting in the 13th month of the term through the 81st month of the term, the loan can be pre-paid at par plus 1.00% of the unpaid principal balance and at par during the last three months of the term.
Loan prepayment fee as a percentage of unpaid principal balance	1.00%
13th month through 81st month \| Cedar Pointe \| Debt With Floating Interest Rate
Debt Instrument [Line Items]
Mortgage loans payable description	Loan can be pre-paid in the first 12 months of the term in certain circumstances at par plus 5.00%. Starting in the 13th month of the term through the 81st month of the term, the loan can be pre-paid at par plus 1.00% of the unpaid principal balance and at par during the last three months of the term.
Loan prepayment fee as a percentage of unpaid principal balance	1.00%
13th month through 81st month \| Bella Vista \| Debt With Floating Interest Rate
Debt Instrument [Line Items]
Mortgage loans payable description	Loan can be pre-paid in the first 12 months of the term in certain circumstances at par plus 5.00%. Starting in the 13th month of the term through the 81st month of the term, the loan can be pre-paid at par plus 1.00% of the unpaid principal balance and at par during the last three months of the term.
Loan prepayment fee as a percentage of unpaid principal balance	1.00%
First 12 months
Debt Instrument [Line Items]
Loan prepayment fee as a percentage of unpaid principal balance	5.00%
First 12 months \| Cedar Pointe \| Debt With Floating Interest Rate
Debt Instrument [Line Items]
Loan prepayment fee as a percentage of unpaid principal balance	5.00%
First 12 months \| Bella Vista \| Debt With Floating Interest Rate
Debt Instrument [Line Items]
Loan prepayment fee as a percentage of unpaid principal balance	5.00%
First Mortgage \| Cornerstone \| Debt With Fixed Interest Rate
Debt Instrument [Line Items]
Debt instrument, payment terms	At the time of acquisition, the principal balance of the first mortgage remained unchanged and had a remaining term of 98 months with 2 months of interest only. The first mortgage is pre-payable and subject to yield maintenance from the 13th month through August 31, 2022 and is pre-payable at par September 1, 2022 until maturity.
Second Mortgage \| Cornerstone \| Debt With Fixed Interest Rate
Debt Instrument [Line Items]
Interest Rate	4.70%
Debt instrument, payment terms	The supplemental second mortgage is pre-payable and subject to yield maintenance from the date of issuance through August 31, 2022 and is pre-payable at par September 1, 2022 until maturity.
Acquired property mortgage loan principle amount	$ 5,800
Last Four Months \| Parc500
Debt Instrument [Line Items]
Mortgage loans payable description	Debt was assumed upon acquisition of this property and recorded at approximated fair value. The loan is open to pre-payment in the last four months of the term.
One-month LIBOR
Debt Instrument [Line Items]
Interest Rate	2.4945%
Held For Sale Properties
Debt Instrument [Line Items]
Deferred financing costs, net of accumulated amortization	$ 100

Loan prepayment fee as percentage of unpaid mortgage principal balance.

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- Definition

Amount of decrease in investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate, from collection of principal.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 12
-Footnote 6
-Subsection 29

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 948
-SubTopic 310
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-29(Footnote 6))
-URI http://asc.fasb.org/extlink&oid=6589523&loc=d3e617274-123014

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- Definition

Description of contractual payment terms of mortgage loan within investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate. Includes, but is not limited to, whether mortgage loan is payable at level or varying amount to maturity, balloon payment requirement at maturity, and prepayment penalty.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 12
-Paragraph Column D
-Subsection 29

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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- Definition

Amount of accumulated amortization of debt issuance costs.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Fair value at acquisition of acquired loans accounted for as debt securities with evidence of deterioration of credit quality.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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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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- Definition

Description of the payment terms of the debt instrument (for example, whether periodic payments include principal and frequency of payments) and discussion about any contingencies associated with the payment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

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