Organization (Details) ft² in Millions	Dec. 31, 2020 a ft² apartment property
Commercial Properties
Real Estate Properties [Line Items]
Number of real estate properties	6
Area (sq ft) \| ft²	1.6
Office Building
Real Estate Properties [Line Items]
Number of real estate properties	5
Retail Site
Real Estate Properties [Line Items]
Number of real estate properties	1
Apartment Building
Real Estate Properties [Line Items]
Number of real estate properties	10
Number of units in real estate property \| apartment	1,639
Developed and Undeveloped Land
Real Estate Properties [Line Items]
Area of land (acres) \| a	1,980
Unconsolidated joint venture
Real Estate Properties [Line Items]
Number of units in real estate property \| apartment	10,137
Percentage ownership	50.00%
Unconsolidated joint venture \| Apartment Building
Real Estate Properties [Line Items]
Number of real estate properties	51
ARL \| Affiliate \| Related party entities
Real Estate Properties [Line Items]
Ownership interest	80.00%
TCI
Real Estate Properties [Line Items]
Ownership interest	78.40%

Area of land held.

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- Definition

Area of a real estate property.

+ References

No definition available.

+ Details

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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

+ Details

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- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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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.

+ Details

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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.

+ Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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