Annual report pursuant to Section 13 and 15(d)

Recent Transactions (Other Investments) (Narrative) (Details)

v3.6.0.2
Recent Transactions (Other Investments) (Narrative) (Details)
$ in Thousands
12 Months Ended
Apr. 26, 2016
USD ($)
Dec. 31, 2016
USD ($)
ft²
item
Dec. 31, 2015
USD ($)
Dec. 31, 2014
USD ($)
Real Estate Properties [Line Items]        
Purchase price of property | $   $ 121,582 $ 94,073 $ 91,813
Weehawken, New Jersey [Member]        
Real Estate Properties [Line Items]        
Purchase price of property | $ $ 36,400      
Port Imperial 4/5 Garage And Retail [Member] | Projects Under Development And Developable Land [Member]        
Real Estate Properties [Line Items]        
Number of units | item   1,100    
Area of property (in square feet) | ft²   290,000    
Percentage of interest in venture   52.50%    
Port Imperial South 11 [Member] | Weehawken, New Jersey [Member]        
Real Estate Properties [Line Items]        
Number of units | item   295