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v3.20.2

Basis of Presentation and Principles of Consolidation and Significant Accounting Policies - Additional Information (Details) $ in Thousands | 3 Months Ended | 9 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | ---
Sep. 30, 2020 USD ($) ft² Property Community State shares | Sep. 30, 2019 USD ($) shares | Sep. 30, 2020 USD ($) ft² Property Community State shares | Sep. 30, 2019 USD ($) shares | Dec. 31, 2022 Property | Dec. 31, 2021 Property | Dec. 31, 2020 Property | Dec. 31, 2019 USD ($) shares
Real Estate Properties [Line Items] |  |  |  |  |  |  |  |
General Partners' Capital Account, Units Outstanding | shares | 114,369,812 | 114,065,859 | 114,369,812 | 114,065,859 |  |  |  |
Number of Real Estate Properties | Community | 299 |  | 299 |  |  |  |  |
Development and capital improvements in progress | $ 220,685 |  | $ 220,685 |  |  |  |  | $ 116,424
Number of States in which Entity Operates | State | 16 |  | 16 |  |  |  |  |
Other non-operating expense (income) | $ 242 | $ 18,800 | $ (13,647) | $ 23,494 |  |  |  |
Consolidated assets | 11,128,704 |  | 11,128,704 |  |  |  |  | 11,230,450
Consolidated liabilities | 4,995,608 |  | 4,995,608 |  |  |  |  | 4,926,860
Real Estate Investments, Joint Ventures | 21,300 |  | $ 21,300 |  |  |  |  |
Percentage Of Rental Revenue From Leasing Of Apartment Homes |  |  | 93.00% |  |  |  |  |
Percentage Of Reimbursable Revenue From Leasing Of Apartment Homes |  |  | 6.00% |  |  |  |  |
Percentage of Rental Revenue and Other Income From Non-leasing Activities |  |  | 1.00% |  |  |  |  |
Operating Lease, Right-of-Use Asset | 50,100 |  | $ 50,100 |  |  |  |  | 53,800
Operating Lease, Liability | $ 32,181 |  | $ 32,181 |  |  |  |  | 33,100
Operating Lease, Weighted Average Remaining Lease Term | 31 years |  | 31 years |  |  |  |  |
Operating Lease, Weighted Average Discount Rate, Percent | 4.40% |  | 4.40% |  |  |  |  |
Other Assets [Member] |  |  |  |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |  |  |  |
Real Estate Investments, Joint Ventures | $ 21,300 |  | $ 21,300 |  |  |  |  | 13,100
Real Estate | Post Massachusetts Avenue [Member] |  |  |  |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |  |  |  |
Real Estate Investments, Joint Ventures | 43,500 |  | 43,500 |  |  |  |  | 43,700
Real Estate | Variable Interest Entity Primary Beneficiary [Member] |  |  |  |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |  |  |  |
Consolidated assets | 96,000 |  | 96,000 |  |  |  |  | 46,000
Consolidated liabilities | $ 10,200 |  | $ 10,200 |  |  |  |  | $ 3,200
Previously Reported [Member] | General and Administrative Expenses [Member] |  |  |  |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |  |  |  |
Other non-operating expense (income) |  | 1,300 |  | 2,300 |  |  |  |
Minimum [Member] |  |  |  |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |  |  |  |
Percentage of ownership interests of all consolidated subsidiaries (percent) | 80.00% |  | 80.00% |  |  |  |  |
Maximum [Member] |  |  |  |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |  |  |  |
Percentage of ownership interests of all consolidated subsidiaries (percent) | 100.00% |  | 100.00% |  |  |  |  |
Maximum [Member] | Accounting Standards Update 2016-02 [Member] |  |  |  |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |  |  |  |
Operating lease, term of contract | 1 year |  | 1 year |  |  |  |  |
Limited Partner [Member] |  |  |  |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |  |  |  |
General Partners' Capital Account, Units Outstanding | shares | 114,369,812 |  | 114,369,812 |  |  |  |  | 114,246,393
Number of Real Estate Properties | Property | 1 |  | 1 |  |  |  |  |
Development and capital improvements in progress | $ 220,685 |  | $ 220,685 |  |  |  |  | $ 116,424
Other non-operating expense (income) | 242 | $ 18,800 | (13,647) | $ 23,494 |  |  |  |
Consolidated assets | 11,128,704 |  | 11,128,704 |  |  |  |  | 11,230,450
Consolidated liabilities | $ 4,995,627 |  | $ 4,995,627 |  |  |  |  | $ 4,926,879
Limited Partner [Member] | Minimum [Member] |  |  |  |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |  |  |  |
Percentage of ownership interests of all consolidated subsidiaries (percent) | 80.00% |  | 80.00% |  |  |  |  |
Limited Partner [Member] | Maximum [Member] |  |  |  |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |  |  |  |
Percentage of ownership interests of all consolidated subsidiaries (percent) | 100.00% |  | 100.00% |  |  |  |  |
Development Properties |  |  |  |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |  |  |  |
Number of Real Estate Properties | Community | 6 |  | 6 |  |  |  |  |
Number of units under development community | Property | 1,940 |  | 1,940 |  |  |  |  |
Development Properties | Expected Costs |  |  |  |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |  |  |  |
Development and capital improvements in progress | $ 459,500 |  | $ 459,500 |  |  |  |  |
Development Properties | Costs Incurred To Date |  |  |  |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |  |  |  |
Development and capital improvements in progress | $ 264,000 |  | $ 264,000 |  |  |  |  |
Development Properties | Scenario Forecast [Member] |  |  |  |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |  |  |  |
Number of Real Estate Properties | Property |  |  |  |  | 1 | 4 | 1 |
Retail |  |  |  |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |  |  |  |
Number of Real Estate Properties | Property | 32 |  | 32 |  |  |  |  |
Square Footage of Real Estate Property | ft² | 630,000 |  | 630,000 |  |  |  |  |
Commercial Real Estate [Member] |  |  |  |  |  |  |  |
Real Estate Properties [Line Items] |  |  |  |  |  |  |  |
Number of Real Estate Properties | Property | 4 |  | 4 |  |  |  |  |
Square Footage of Real Estate Property | ft² | 260,000 |  | 260,000 |  |  |  |  |
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 |  |  | 96.60% | 96.60% |  |  |  |

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