Annual report pursuant to Section 13 and 15(d)

Organization And Basis Of Presentation (Narrative) (Details)

v3.22.0.1
Organization And Basis Of Presentation (Narrative) (Details)
$ in Millions
 12 Months Ended
Dec. 31, 2021
USD ($)
ft²
property
item
Dec. 31, 2020
USD ($)
ft²
item
Dec. 19, 2019
ft²
Real Estate Properties [Line Items]      
Percentage of ownership interest 91.00% 90.40%  
Number of properties owned or investment interests 36    
Number of units | item 506 326  
Consolidated joint ventures, total real estate assets | $ $ 477.5 $ 486.1  
Consolidated joint ventures, other assets | $ 5.3 4.5  
Consolidated joint ventures, mortgages | $ 285.7 284.8  
Consolidated joint ventures, other liabilities | $ $ 21.2 $ 21.0  
Area of property (in square feet) | ft² 3,049,313 2,725,639  
Increase in land and other impairments | $   $ 2.5  
Company Controlled Properties [Member]      
Real Estate Properties [Line Items]      
Number of properties owned or investment interests 27    
Multi-Family Properties [Member]      
Real Estate Properties [Line Items]      
Number of properties owned or investment interests 22    
Non-Core Assets [Member]      
Real Estate Properties [Line Items]      
Number of properties owned or investment interests 12    
Multi-Family Properties, Investment [Member]      
Real Estate Properties [Line Items]      
Number of properties owned or investment interests 7    
Non-Core Assets, Investment [Member]      
Real Estate Properties [Line Items]      
Number of properties owned or investment interests 2    
Multi-Family Properties, Company Controlled [Member]      
Real Estate Properties [Line Items]      
Number of properties owned or investment interests 15    
Office [Member]      
Real Estate Properties [Line Items]      
Number of properties owned or investment interests 7    
Unconsolidated Joint Ventures Office And Retail Properties [Member]      
Real Estate Properties [Line Items]      
Number of properties owned or investment interests 9    
Unconsolidated Joint Venture Multi-Family Properties [Member]      
Real Estate Properties [Line Items]      
Number of units | item 2,146    
Unconsolidated Joint Venture Office/Flex Buildings And Hotel [Member]      
Real Estate Properties [Line Items]      
Number of properties owned or investment interests 3    
Parking/Retail [Member]      
Real Estate Properties [Line Items]      
Number of properties owned or investment interests 4    
Suburban Office Portfolio [Member]      
Real Estate Properties [Line Items]      
Area of property (in square feet) | ft²     6,600,000