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v3.21.2

Basis of Presentation and Principles of Consolidation and Significant Accounting Policies - Additional Information (Details) | 9 Months Ended |  |  |
--- | --- | --- | --- | ---
Sep. 30, 2021 USD ($) Properties Property State Community shares | Sep. 30, 2020 shares | Dec. 31, 2022 Property | Dec. 31, 2021 Property | Dec. 31, 2020 USD ($) Property shares
Real Estate Properties [Line Items] |  |  |  |  |
General Partners' Capital Account, Units Outstanding | shares | 115,138,323 | 114,369,812 |  |  |
Number of Real Estate Properties | Community | 296 |  |  |  |
Development and capital improvements in progress | $ 236,339,000 |  |  |  | $ 283,477,000
Number of States in which Entity Operates | State | 16 |  |  |  |
Consolidated assets | $ 11,254,132,000 |  |  |  | 11,194,791,000
Consolidated liabilities | 5,139,479,000 |  |  |  | 5,090,986,000
Real Estate Investments, Joint Ventures | 18,700,000 |  |  |  |
Operating Lease, Right-of-Use Asset | 47,700,000 |  |  |  | 49,400,000
Operating Lease, Liability | $ 30,718,000 |  |  |  | 31,700,000
Operating Lease, Weighted Average Remaining Lease Term | 32 years |  |  |  |
Operating Lease, Weighted Average Discount Rate, Percent | 4.40% |  |  |  |
Other Assets [Member] |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |
Real Estate Investments, Joint Ventures | $ 43,000,000.0 |  |  |  | 23,000,000.0
Real Estate [Member] | Post Massachusetts Avenue [Member] |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |
Real Estate Investments, Joint Ventures | 42,800,000 |  |  |  | 43,300
Real Estate [Member] | Variable Interest Entity Primary Beneficiary [Member] |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |
Consolidated assets | 218,800,000 |  |  |  | 128,900,000
Consolidated liabilities | $ 15,300,000 |  |  |  | $ 8,100
Minimum [Member] |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |
Percentage of ownership interests of all consolidated subsidiaries (percent) | 80.00% |  |  |  |
Maximum [Member] |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |
Percentage of ownership interests of all consolidated subsidiaries (percent) | 100.00% |  |  |  |
Maximum [Member] | Accounting Standards Update 2016-02 [Member] |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |
Operating lease, term of contract | 1 year |  |  |  |
Limited Partner [Member] |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |
General Partners' Capital Account, Units Outstanding | shares | 115,138,323 |  |  |  | 114,373,727
Number of Real Estate Properties | Property | 1 |  |  |  |
Development and capital improvements in progress | $ 236,339,000 |  |  |  | $ 283,477,000
Consolidated assets | 11,254,132,000 |  |  |  | 11,194,791,000
Consolidated liabilities | $ 5,139,498,000 |  |  |  | $ 5,091,005,000
Limited Partner [Member] | Minimum [Member] |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |
Percentage of ownership interests of all consolidated subsidiaries (percent) | 80.00% |  |  |  |
Limited Partner [Member] | Maximum [Member] |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |
Percentage of ownership interests of all consolidated subsidiaries (percent) | 100.00% |  |  |  |
Development Properties [Member] |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |
Number of Real Estate Properties | 8 |  |  |  | 3
Number of units under development community | Properties | 2,654 |  |  |  |
Development Properties [Member] | Expected Costs |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |
Development and capital improvements in progress | $ 627,500,000 |  |  |  |
Development Properties [Member] | Costs Incurred To Date |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |
Development and capital improvements in progress | $ 383,800 |  |  |  |
Development Properties [Member] | Scenario Forecast [Member] |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |
Number of Real Estate Properties | Property |  |  | 3 | 2 |
Retail |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |
Number of Real Estate Properties | Property | 32 |  |  |  |
M A A L P |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |
Limited Liability Company (LLC) or Limited Partnership (LP), Managing Member or General Partner, Ownership Interest | 97.10% | 96.60% |  |  |

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