Quarterly report pursuant to Section 13 or 15(d)

Recent Transactions (Real Estate Held For Sale/Discontinued Operations/Dispositions) (Narrative) (Details)

v3.21.2
Recent Transactions (Real Estate Held For Sale/Discontinued Operations/Dispositions) (Narrative) (Details)
$ in Thousands
3 Months Ended 6 Months Ended 27 Months Ended
May 24, 2021
USD ($)
Jun. 30, 2021
USD ($)
ft²
item
property
Jun. 30, 2020
USD ($)
Jun. 30, 2021
USD ($)
ft²
property
item
Jun. 30, 2020
USD ($)
Mar. 31, 2021
USD ($)
ft²
property
Dec. 31, 2020
USD ($)
Dec. 19, 2019
ft²
Real Estate Properties [Line Items]                
Unrealized gains (losses) on real estate held for sale       $ (485)        
Land and other impairments   $ 7,519 $ 16,846 7,932 $ 22,109      
Proceeds from the sale of property       42,702 $ 16,455      
Book value   $ 4,743,736   $ 4,743,736     $ 4,638,643  
Suburban Office Portfolio [Member]                
Real Estate Properties [Line Items]                
Area of property (in square feet) | ft²               6,600,000
Disposal Group, Held-for-sale, Not Discontinued Operations [Member] | Suburban Office Portfolio [Member]                
Real Estate Properties [Line Items]                
Number of real estate properties | item   2   2        
Disposal Group, Held-for-sale, Not Discontinued Operations [Member] | Properties Disposed One [Member] | Suburban Office Portfolio [Member]                
Real Estate Properties [Line Items]                
Number of real estate properties | property   2   2        
Area of property (in square feet) | ft²   500,000   500,000        
Disposal Group, Held-for-sale, Not Discontinued Operations [Member] | Office [Member]                
Real Estate Properties [Line Items]                
Number of properties held for sale | property   2   2        
Number of disposal groups | property       2        
Disposal Group, Not Discontinued Operations [Member]                
Real Estate Properties [Line Items]                
Unrealized gains (losses) on real estate held for sale       $ (2,130)        
Area Of Real Estate Property Sold | ft²   2,564,159   2,564,159        
Gain (loss) on sale of property       $ 26,991        
Disposal Group, Not Discontinued Operations [Member] | Suburban Office Portfolio [Member]                
Real Estate Properties [Line Items]                
Area of property (in square feet) | ft²           5,800,000    
Gain (loss) on sale of property           $ 989,000    
Disposal Group, Not Discontinued Operations [Member] | Properties Disposed One [Member] | Suburban Office Portfolio [Member]                
Real Estate Properties [Line Items]                
Number of properties sold | property           34    
Disposal Group, Not Discontinued Operations [Member] | Properties Disposed Two [Member] | Suburban Office Portfolio [Member]                
Real Estate Properties [Line Items]                
Gain (loss) on sale of property       54,300        
Parsippany, Madison, Short Hills, Edison, And Red Bank, New Jersey [Member]                
Real Estate Properties [Line Items]                
Unrealized gains (losses) on real estate held for sale   $ 1,400   $ 2,600        
Parsippany, Madison, Short Hills, Edison, And Red Bank, New Jersey [Member] | Disposal Group, Held-for-sale, Not Discontinued Operations [Member]                
Real Estate Properties [Line Items]                
Number of properties held for sale | property   3   3        
Unrealized gains (losses) on real estate held for sale   $ 1,400   $ 2,600        
Land and other impairments       400        
Parsippany, Madison, Short Hills, Edison, And Red Bank, New Jersey [Member] | Discontinued Operations [Member]                
Real Estate Properties [Line Items]                
Unrealized gains (losses) on real estate held for sale   1,000   $ 2,100        
Land and other impairments   $ 400            
Hamilton, New Jersey [Member] | Disposal Group, Held-for-sale, Not Discontinued Operations [Member]                
Real Estate Properties [Line Items]                
Gain (loss) on sale of property $ 111              
Proceeds from the sale of property $ 745