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v3.19.3.a.u2

Organization and Summary of Significant Accounting Policies (Textual) (Details) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2019 USD ($) ft² Property Communitie State shares | Dec. 31, 2018 USD ($) shares | Dec. 31, 2017 USD ($) | Jan. 01, 2019
Real Estate Properties [Line Items] |  |  |  |
General Partners' Capital Account, Units Outstanding | shares | 114,246,393 | 113,844,267 |  |
Number of Real Estate Properties | Communitie | 299 |  |  |
Development and capital improvements in progress | $ 116,424 | $ 59,506 |  |
Number of States in which Entity Operates | State | 16 |  |  |
Consolidated assets | $ 11,230,450 | 11,323,781 |  |
Consolidated liabilities | 4,926,860 | 4,942,178 |  |
Advertising expenses | 20,800 | 20,200 | $ 18,800 |
Lease Intangibles, Gross | 13,864,159 | 13,598,550 |  |
Operating Lease, Right-of-Use Asset | 54,300 |  |  |
Operating Lease, Liability | $ 33,119 |  |  |
Operating Lease, Weighted Average Remaining Lease Term |  |  |  | 33 years
Operating Lease, Weighted Average Discount Rate, Percent | 4.40% |  |  |
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% |  |  |
Accounting Standards Update 2016-02 |  |  |  |
Real Estate Properties [Line Items] |  |  |  |
Operating Lease, Right-of-Use Asset | $ 53,800 |  |  |
Operating Lease, Liability | $ 33,600 |  |  |
Operating Lease, Weighted Average Remaining Lease Term | 32 years |  |  |
Accrued Liabilities [Member] |  |  |  |
Real Estate Properties [Line Items] |  |  |  |
Dividends Payable | $ 118,300 | 113,200 |  |
Accrued Real Estate Taxes | 131,900 | 123,500 |  |
Unearned Income | 42,000 | 41,100 |  |
Loss Contingency, Loss in Period | 8,600 | 8,700 |  |
Security Deposit Liability | 19,400 | 18,700 |  |
Interest Payable | $ 21,400 | 15,100 |  |
Furniture, Fixtures And Equipment |  |  |  |
Real Estate Properties [Line Items] |  |  |  |
Equipment, Useful Life | 5 years |  |  |
Leases, Acquired-in-Place |  |  |  |
Real Estate Properties [Line Items] |  |  |  |
Lease Intangibles, Gross | $ 2,600 | 3,900 |  |
Parent Company |  |  |  |
Real Estate Properties [Line Items] |  |  |  |
Capitalized Development Costs, Period | 6,500 | 4,200 | $ 11,000 |
Real Estate |  |  |  |
Real Estate Properties [Line Items] |  |  |  |
Cash proceeds | 10,900 |  |  |
Real Estate Investments, Joint Ventures | 8,200 |  |  |
Real Estate | Other Assets [Member] |  |  |  |
Real Estate Properties [Line Items] |  |  |  |
Real Estate Investments, Joint Ventures | 13,100 | 3,800 |  |
Real Estate | Post Massachusetts Avenue |  |  |  |
Real Estate Properties [Line Items] |  |  |  |
Real Estate Investments, Joint Ventures | 43,700 | 44,200 |  |
Real Estate | Variable Interest Entity Primary Beneficiary [Member] |  |  |  |
Real Estate Properties [Line Items] |  |  |  |
Consolidated assets | 46,000 | 85,700 |  |
Consolidated liabilities | $ 3,200 | $ 1,300 |  |
Minimum [Member] |  |  |  |
Real Estate Properties [Line Items] |  |  |  |
Percentage of ownership interests of all consolidated subsidiaries (percent) | 80.00% |  |  |
Minimum [Member] | Land Improvements And Buildings |  |  |  |
Real Estate Properties [Line Items] |  |  |  |
Equipment, Useful Life | 8 years |  |  |
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 |  |  |  |
Real Estate Properties [Line Items] |  |  |  |
Operating lease, term of contract | 1 year |  |  |
Maximum [Member] | Land Improvements And Buildings |  |  |  |
Real Estate Properties [Line Items] |  |  |  |
Equipment, Useful Life | 40 years |  |  |
Development Properties |  |  |  |
Real Estate Properties [Line Items] |  |  |  |
Number of Real Estate Properties | Communitie | 7 |  |  |
Number of units under development community | Property | 2,108 |  |  |
Development Properties | Expected Costs |  |  |  |
Real Estate Properties [Line Items] |  |  |  |
Development and capital improvements in progress | $ 489,500 |  |  |
Development Properties | Costs Incurred To Date |  |  |  |
Real Estate Properties [Line Items] |  |  |  |
Development and capital improvements in progress | $ 143,900 |  |  |
Retail |  |  |  |
Real Estate Properties [Line Items] |  |  |  |
Number of Real Estate Properties | Property | 32 |  |  |
Square footage of real estate property | ft² | 630,000 |  |  |
Commercial Real Estate [Member] |  |  |  |
Real Estate Properties [Line Items] |  |  |  |
Number of Real Estate Properties | Property | 4 |  |  |
Square footage of real estate property | ft² | 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% | 96.50% |  |

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Data Type: | na
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