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Commitments and Contingencies - Additional Information (Details) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Jun. 30, 2021 Agreement | Sep. 30, 2021 USD ($) Property ApartmentUnit Agreement
Commitments and Contingencies [Line Items] |  |
Number of consolidated projects in various stages of development |  | 2
Consolidated wholly owned projects in various stages of development |  | 1
Consolidated partially owned projects in various stages of development |  | 1
Number of unconsolidated projects in various stages of development |  | 2
Number of consolidated projects in lease-up |  | 2
Partially owned consolidated projects in lease-up |  | 1
Wholly owned consolidated projects in lease-up |  | 1
Units in various stages of development | ApartmentUnit |  | 1,441
Consolidated project under development commitment fund | $ |  | $ 328.8
Various stages of development with estimated completion dates ranging through Jun 30, 2024 |  | Jun. 30, 2024
Number of joint venture agreement | Agreement |  | 2
Number of joint venture agreement completed | Agreement | 1 |
Number of joint venture agreement currently under construction | Agreement |  | 1
Number of unconsolidated joint venture agreements | Agreement |  | 2
Equity method investment period |  | 3 years
Percentage of expected non-recourse construction debt |  | 60.00%
Initial minimum co-investment of combined equity | $ |  | $ 750.0
Equity Residential [Member] |  |
Commitments and Contingencies [Line Items] |  |
Ownership Percentage |  | 75.00%
Toll Brothers Inc. [Member] |  |
Commitments and Contingencies [Line Items] |  |
Ownership Percentage |  | 25.00%

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- Definition Represents the company's remaining funding obligation (i.e. total project costs less book value) for consolidated projects that are under development. + References No definition available. + Details
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- Definition Number of joint venture agreement. + References No definition available. + Details
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- Definition Number of joint venture agreement completed. + References No definition available. + Details
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- Definition Number of joint venture agreement currently under construction. + References No definition available. + Details
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- Definition Number of partially owned consolidated projects. + References No definition available. + Details
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- Definition Number of partially owned consolidated projects in lease up. + References No definition available. + Details
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- Definition Number of unconsolidated joint venture agreements. + References No definition available. + Details
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- Definition Number of unconsolidated projects in various stages of development. + References No definition available. + Details
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- Definition Total number of units that are associated with open development projects. May include projects that are held for and/or under development, completed and not stabilized or completed and stabilized. These units are consolidated. + References No definition available. + Details
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- Definition Percentage of expected non-recourse construction debt. + 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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