Recent Transactions (Schedule Of Purchase Price Allocation) (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
In-Place Leases [Member]    
Business Acquisition [Line Items]    
Amortization period   10 years
Above Market, In-Place And Below Market Leases [Member]    
Business Acquisition [Line Items]    
Amortization period 8 years 1 month 6 days  
11 Martine Avenue [Member]    
Business Acquisition [Line Items]    
Land $ 2,460  
Buildings and improvements 8,290  
Net assets recorded upon acquisition/consolidation 10,750  
320, 321 University Avenue [Member]    
Business Acquisition [Line Items]    
Land 7,305  
Buildings and improvements 15,695  
Net assets recorded upon acquisition/consolidation 23,000  
101 Wood Avenue South [Member]    
Business Acquisition [Line Items]    
Land 8,509  
Buildings and improvements 72,738  
Above market leases [1] 58  
In-place lease values [1] 6,743  
Sub Total 88,048  
Less: Below market lease values [1] (5,748)  
Net assets recorded upon acquisition/consolidation 82,300  
111 River Street [Member]    
Business Acquisition [Line Items]    
Land 204  
Buildings and improvements 198,609  
Above market leases [1] 617  
In-place lease values [1] 43,801  
Other assets 11,279  
Sub Total 254,510  
Less: Below market lease values [1] (43,749)  
Net assets recorded upon acquisition/consolidation $ 210,761  
Parsippany [Member]    
Business Acquisition [Line Items]    
Land   $ 5,590
Buildings and improvements   4,710
Net assets recorded upon acquisition/consolidation   10,300
Edison [Member]    
Business Acquisition [Line Items]    
Land   5,542
Buildings and improvements   40,762
Above market leases [2]   2,097
In-place lease values [2]   4,699
Net assets recorded upon acquisition/consolidation   $ 53,100
[1] Above market, in-place and below market leases are being amortized over a weighted-average term of 8.1 years.
[2] In-place lease values will be amortized over four years or less, and above market leases will be amortized over 10 years or less.