Quarterly report pursuant to Section 13 or 15(d)

Organization And Basis Of Presentation (Narrative) (Details)

v3.20.2
Organization And Basis Of Presentation (Narrative) (Details)
$ in Millions
 3 Months Ended 6 Months Ended
Jun. 30, 2020
USD ($)
ft²
room
item
Jun. 30, 2020
USD ($)
ft²
property
item
state
room
Dec. 31, 2019
USD ($)
Dec. 19, 2019
ft²
Real Estate Properties [Line Items]        
Percentage of ownership interest 90.40% 90.40% 90.40%  
Number of properties owned or investment interests   71    
Number of states where properties are located | state   4    
Consolidated joint ventures, total real estate assets | $ $ 495.0 $ 495.0 $ 503.1  
Consolidated joint ventures, mortgages | $ 283.6 283.6 283.7  
Consolidated joint ventures, other liabilities | $ 19.7 19.7 $ 18.9  
Increase in land and other impairments | $ $ 2.5 $ 2.5    
Commercial Properties [Member]        
Real Estate Properties [Line Items]        
Number of tenants | item 325 325    
Multi-Family Properties [Member]        
Real Estate Properties [Line Items]        
Number of properties owned or investment interests   22    
Number of units | item 6,850 6,850    
Office [Member]        
Real Estate Properties [Line Items]        
Number of properties owned or investment interests   41    
Aggregate square feet of the property owned or investment interest | ft²   10,500,000    
Unconsolidated Joint Venture Office Buildings [Member]        
Real Estate Properties [Line Items]        
Number of properties owned or investment interests   2    
Aggregate square feet of the property owned or investment interest | ft²   200,000    
Area of property (in square feet) | ft² 200,000 200,000    
Unconsolidated Joint Venture Multi-Family Properties [Member]        
Real Estate Properties [Line Items]        
Number of properties owned or investment interests   7    
Number of units | item 2,611 2,611    
Unconsolidated Joint Venture Office/Flex Buildings And Hotel [Member]        
Real Estate Properties [Line Items]        
Number of properties owned or investment interests   3    
Number of units | room 723 723    
Parking/Retail [Member]        
Real Estate Properties [Line Items]        
Number of properties owned or investment interests   4    
Aggregate square feet of the property owned or investment interest | ft²   108,000    
Unconsolidated Joint Venture Parking/Retail Buildings [Member]        
Real Estate Properties [Line Items]        
Number of properties owned or investment interests   1    
Aggregate square feet of the property owned or investment interest | ft²   51,000    
Land [Member]        
Real Estate Properties [Line Items]        
Number of properties owned or investment interests   1    
Suburban Office Portfolio [Member]        
Real Estate Properties [Line Items]        
Area of property (in square feet) | ft²       6,600,000