v3.26.1
Organization and Summary of Significant Accounting Policies - Additional Information (Details)
$ in Thousands
3 Months Ended 6 Months Ended
Jun. 30, 2026
USD ($)
ApartmentUnits
State
Property
Community
shares
Jun. 30, 2025
USD ($)
shares
Jun. 30, 2026
USD ($)
ApartmentUnits
State
Property
Community
shares
Jun. 30, 2025
USD ($)
shares
Dec. 31, 2028
Property
Dec. 31, 2027
Property
Dec. 31, 2025
USD ($)
shares
Real Estate Properties [Line Items]              
General Partners' Capital Account, Units Outstanding | shares 116,015,088 117,071,410 116,015,088 117,071,410      
Number of Real Estate Properties | Community 294   294        
Number of units under development community | ApartmentUnits 1,749   1,749        
Development and capital improvements in progress $ 406,830   $ 406,830       $ 426,759
Number of States in which Entity Operates | State 16   16        
Consolidated assets $ 11,994,584   $ 11,994,584       11,975,383
Consolidated liabilities 6,393,083   6,393,083       $ 6,135,738
Real Estate Investments, Joint Ventures $ 19,500   $ 19,500        
Percentage Of Rental Revenue From Leasing Of Apartment Homes     94.00%        
Percentage Of Reimbursable Revenue From Leasing Of Apartment Homes     5.00%        
Percentage of Rental Revenue and Other Income From Non-leasing Activities     1.00%        
Operating Lease, Right-of-Use Asset, Statement of Financial Position Other assets   Other assets       Other assets
Operating Lease, Liability, Statement of Financial Position [Extensible Enumeration] Accrued expenses and other liabilities   Accrued expenses and other liabilities       Accrued expenses and other liabilities
Operating Lease, Right-of-Use Asset $ 36,700   $ 36,700       $ 38,000
Right-of-use Lease, Liability 23,367   23,367       24,300
Marketable equity securities 2,300   2,300       3,900
Marketable Equity Securities [Member]              
Real Estate Properties [Line Items]              
Unrealized gains (losses) (600) $ (400) (1,600) $ (1,400)      
Limited Partnership [Member]              
Real Estate Properties [Line Items]              
Investment Income     22,100 $ 1,600      
Investment Expense 800 $ 100          
Other Assets [Member]              
Real Estate Properties [Line Items]              
Real Estate Investments, Joint Ventures 100,900   100,900       78,200
Real Estate [Member]              
Real Estate Properties [Line Items]              
Proceeds from (Payments to) Noncontrolling Interests     11,000        
Real Estate [Member] | Post Massachusetts Avenue [Member]              
Real Estate Properties [Line Items]              
Real Estate Investments, Joint Ventures $ 41,900   $ 41,900       $ 41,300
Maximum [Member] | Accounting Standards Update 2016-02 [Member]              
Real Estate Properties [Line Items]              
Operating lease, term of contract 1 year   1 year        
Development Properties [Member] | Scenario Forecast [Member]              
Real Estate Properties [Line Items]              
Number of Real Estate Properties | Property         2 2  
Retail [Member]              
Real Estate Properties [Line Items]              
Number of Real Estate Properties | Property 37   37        
M A A L P [Member]              
Real Estate Properties [Line Items]              
Limited Liability Company (LLC) or Limited Partnership (LP), Managing Member or General Partner, Ownership Interest     97.50% 97.50%      
Limited Partnership [Member]              
Real Estate Properties [Line Items]              
General Partners' Capital Account, Units Outstanding | shares 116,015,088   116,015,088       116,878,077
Number of Real Estate Properties | Property 1   1        
Development and capital improvements in progress $ 406,830   $ 406,830       $ 426,759
Consolidated assets 11,994,584   11,994,584       11,975,383
Consolidated liabilities $ 6,393,102   $ 6,393,102       6,135,757
Limited Partnership [Member] | Minimum [Member]              
Real Estate Properties [Line Items]              
Percentage of ownership interests of all consolidated subsidiaries (percent) 95.00%   95.00%        
Limited Partnership [Member] | Maximum [Member]              
Real Estate Properties [Line Items]              
Percentage of ownership interests of all consolidated subsidiaries (percent) 100.00%   100.00%        
Limited Partnership [Member] | Development Properties [Member] | Costs Incurred To Date [Member]              
Real Estate Properties [Line Items]              
Development and capital improvements in progress $ 360,400   $ 360,400        
Limited Partnership [Member] | Variable Interest Entity Primary Beneficiary [Member] | Real Estate [Member]              
Real Estate Properties [Line Items]              
Consolidated assets 429,900   429,900       386,400
Consolidated liabilities $ 14,900   $ 14,900       $ 16,700