Organization and Background (Details) $ in Thousands	Jun. 30, 2021 USD ($) property investment state property_unit	Dec. 31, 2020 USD ($) property
Real Estate Properties [Line Items]
Number of properties \| property	7
Number of states \| state	6
Number of units \| property_unit	1,608
Real estate properties, net of accumulated depreciation	$ 140,991	$ 160,192
Investments in unconsolidated joint ventures	159,799	$ 169,474
Real estate investments, other	6,593
Multi-family
Real Estate Properties [Line Items]
Real estate properties, net of accumulated depreciation	$ 134,458
Unconsolidated Joint Ventures
Real Estate Properties [Line Items]
Number of units \| property_unit	8,954
Unconsolidated Joint Ventures
Real Estate Properties [Line Items]
Number of properties \| property	30	31
Number of states \| state	9
Real estate properties, net of accumulated depreciation	$ 896,944	$ 1,075,178
Number of investments \| investment	30
Investments in unconsolidated joint ventures	$ 159,799
Unconsolidated Joint Ventures \| Minimum
Real Estate Properties [Line Items]
Equity interest percentage	32.00%
Unconsolidated Joint Ventures \| Maximum
Real Estate Properties [Line Items]
Equity interest percentage	90.00%

Equity Method Investments, Number Of Investments

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=109237563&loc=d3e33749-111570

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 25
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8813-108599

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.12)
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- Definition

The number of real estate properties owned as of the balance sheet date.

+ References

No definition available.

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The number of states the entity operates in as of the balance sheet date.

+ References

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- Definition

The number of units in a real estate property owned as of the balance sheet date.

+ References

No definition available.

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- Definition

Amount of real estate investment property, net of accumulated depreciation, which may include the following: (1) land available-for-sale; (2) land available-for-development; (3) investments in building and building improvements; (4) tenant allowances; (5) developments in-process; (6) rental properties; and (7) other real estate investments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
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- Definition

Amount of real estate owned for income production and capital accretion potential, not otherwise specified in the existing taxonomy. Such real estate excludes that which is occupied or used in the business, for entertainment purposes, or held in inventory for specific purposes.

+ References

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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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