Annual report pursuant to Section 13 and 15(d)

Recent Transactions (Schedule Of Disposed Properties) (Details)

v3.19.3.a.u2
Recent Transactions (Schedule Of Disposed Properties) (Details)
 3 Months Ended 6 Months Ended 12 Months Ended
Mar. 31, 2019
USD ($)
property
shares
Jun. 30, 2019
USD ($)
Dec. 31, 2019
USD ($)
ft²
item
property
shares
Dec. 31, 2018
USD ($)
ft²
item
Dec. 31, 2017
USD ($)
property
Mar. 31, 2018
USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]            
New mortgage loan/(repayments)         $ 44,695,000  
Carrying Amount of Mortgages       $ 45,242,000 45,734,000  
Unrealized losses on rental properties held for sale     $ (36,225,000)      
Impairment charge       $ 24,600,000    
Valuation allowance     $ 9,800,000   (5,300,000)  
Number Of Units | item     208 1,317    
Disposal Group, Not Discontinued Operations [Member]            
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]            
Number of Buildings, Disposed | item     68 30    
Number of properties Disposed | property     2      
Rentable Square Feet, Disposed | ft²     4,490,578 2,405,654    
Net Sales Proceeds     $ 1,052,427,000 $ 324,050,000    
Net Carrying Value     668,574,000 204,479,000    
Realized Gains (losses)/Unrealized Losses, net     $ 382,151,000 119,571,000    
Redemption Of Common Units, Shares | shares     301,638      
Carrying Amount of Mortgages     $ 350,000,000      
Unrealized losses on rental properties held for sale       (20,135,000)    
Totals     $ 345,926,000 $ 99,436,000    
Number Of Units | item     377      
Proceeds from sale of properties     $ 6,600,000      
Repayment of mortgage loans     90,000,000      
Funds from qualified intermediary     $ 217,400,000      
Disposal Group, Not Discontinued Operations [Member] | 35 Waterview Boulevard [Member]            
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]            
Number of Buildings, Disposed | item       1    
Rentable Square Feet, Disposed | ft²       172,498    
Net Sales Proceeds       $ 25,994,000    
Net Carrying Value       25,739,000    
Realized Gains (losses)/Unrealized Losses, net       $ 255,000    
Valuation allowance         700,000  
Disposal Group, Not Discontinued Operations [Member] | Hamilton Portfolio [Member]            
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]            
Number of Buildings, Disposed | item       6    
Rentable Square Feet, Disposed | ft²       239,262    
Net Sales Proceeds       $ 17,546,000    
Net Carrying Value       17,501,000    
Realized Gains (losses)/Unrealized Losses, net       $ 45,000    
Valuation allowance         600,000  
Disposal Group, Not Discontinued Operations [Member] | Wall Portfolio First Closing [Member]            
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]            
Number of Buildings, Disposed | item       5    
Rentable Square Feet, Disposed | ft²       179,601    
Net Sales Proceeds       $ 14,053,000    
Net Carrying Value       10,526,000    
Realized Gains (losses)/Unrealized Losses, net       $ 3,527,000    
Disposal Group, Not Discontinued Operations [Member] | 700 Horizon Drive [Member]            
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]            
Number of Buildings, Disposed | item       1    
Rentable Square Feet, Disposed | ft²       120,000    
Net Sales Proceeds       $ 33,020,000    
Net Carrying Value       16,053,000    
Realized Gains (losses)/Unrealized Losses, net       $ 16,967,000    
Disposal Group, Not Discontinued Operations [Member] | Wall Portfolio Second Closing [Member]            
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]            
Number of Buildings, Disposed | item       3    
Rentable Square Feet, Disposed | ft²       217,822    
Net Sales Proceeds       $ 30,209,000    
Net Carrying Value       12,961,000    
Realized Gains (losses)/Unrealized Losses, net       $ 17,248,000    
Disposal Group, Not Discontinued Operations [Member] | 75 Livingston Avenue [Member]            
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]            
Number of Buildings, Disposed | item       1    
Rentable Square Feet, Disposed | ft²       94,221    
Net Sales Proceeds       $ 7,983,000    
Net Carrying Value       5,609,000    
Realized Gains (losses)/Unrealized Losses, net       $ 2,374,000    
Disposal Group, Not Discontinued Operations [Member] | 20 Waterview Boulevard [Member]            
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]            
Number of Buildings, Disposed | item       1    
Rentable Square Feet, Disposed | ft²       225,550    
Net Sales Proceeds       $ 12,475,000    
Net Carrying Value       11,795,000    
Realized Gains (losses)/Unrealized Losses, net       $ 680,000    
Valuation allowance         $ 11,000,000  
Disposal Group, Not Discontinued Operations [Member] | 20 Waterview Boulevard [Member] | Notes Receivable 6.0 Interest Rate [Member] | Buyer [Member]            
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]            
Noncash net sales proceeds           $ 2,800,000
Disposal Group, Not Discontinued Operations [Member] | Westchester Financial Center [Member]            
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]            
Number of Buildings, Disposed | item       2    
Rentable Square Feet, Disposed | ft²       489,000    
Net Sales Proceeds       $ 81,769,000    
Net Carrying Value       64,679,000    
Realized Gains (losses)/Unrealized Losses, net       17,090,000    
Disposal Group, Not Discontinued Operations [Member] | Westchester Financial Center [Member] | Notes Receivable 3.0 Interest Rate [Member] | Buyer [Member]            
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]            
Noncash net sales proceeds       $ 4,000,000.0    
Disposal Group, Not Discontinued Operations [Member] | 65 Jackson Drive [Member]            
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]            
Number of Buildings, Disposed | item       0    
Net Sales Proceeds       $ 1,510,000    
Realized Gains (losses)/Unrealized Losses, net       $ 1,510,000    
Disposal Group, Not Discontinued Operations [Member] | 600 Horizon Drive [Member]            
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]            
Number of Buildings, Disposed | item       1    
Rentable Square Feet, Disposed | ft²       95,000    
Net Sales Proceeds       $ 15,127,000    
Net Carrying Value       6,191,000    
Realized Gains (losses)/Unrealized Losses, net       $ 8,936,000    
Disposal Group, Not Discontinued Operations [Member] | 1 & 3 Barker Avenue [Member]            
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]            
Number of Buildings, Disposed | item       2    
Rentable Square Feet, Disposed | ft²       133,300    
Net Sales Proceeds       $ 15,140,000    
Net Carrying Value       13,543,000    
Realized Gains (losses)/Unrealized Losses, net       $ 1,597,000    
Disposal Group, Not Discontinued Operations [Member] | 120 West Passaic Street [Member]            
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]            
Number of Buildings, Disposed | item       1    
Rentable Square Feet, Disposed | ft²       52,000    
Net Sales Proceeds       $ 2,667,000    
Net Carrying Value       2,568,000    
Realized Gains (losses)/Unrealized Losses, net       $ 99,000    
Disposal Group, Not Discontinued Operations [Member] | Elmsford Distribution Center [Member]            
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]            
Number of Buildings, Disposed | item       6    
Rentable Square Feet, Disposed | ft²       387,400    
Net Sales Proceeds       $ 66,557,000    
Net Carrying Value       17,314,000    
Realized Gains (losses)/Unrealized Losses, net       49,243,000    
Disposal Group, Not Discontinued Operations [Member] | 721 Route 202/206 South [Member]            
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]            
Number of Buildings, Disposed | item     1      
Rentable Square Feet, Disposed | ft²     192,741      
Net Sales Proceeds     $ 5,651,000      
Net Carrying Value     5,410,000      
Realized Gains (losses)/Unrealized Losses, net     $ 241,000      
Valuation allowance       9,300,000    
Disposal Group, Not Discontinued Operations [Member] | Park Square Apartments [Member]            
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]            
Number of Buildings, Disposed | item     1      
Rentable Square Feet, Disposed | ft²     159      
Net Sales Proceeds     $ 34,045,000      
Net Carrying Value     34,032,000      
Realized Gains (losses)/Unrealized Losses, net     $ 13,000      
Valuation allowance       6,300,000    
Disposal Group, Not Discontinued Operations [Member] | 2115 Linwood Avenue [Member]            
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]            
Number of Buildings, Disposed | item     1      
Rentable Square Feet, Disposed | ft²     68,000      
Net Sales Proceeds     $ 15,197,000      
Net Carrying Value     7,433,000      
Realized Gains (losses)/Unrealized Losses, net     $ 7,764,000      
Disposal Group, Not Discontinued Operations [Member] | 201 Littleton Road [Member]            
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]            
Number of Buildings, Disposed | item     1      
Rentable Square Feet, Disposed | ft²     88,369      
Net Sales Proceeds     $ 4,842,000      
Net Carrying Value     4,937,000      
Realized Gains (losses)/Unrealized Losses, net     $ (95,000)      
Valuation allowance       3,600,000    
Disposal Group, Not Discontinued Operations [Member] | 320 & 321 University Avenue [Member]            
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]            
Number of Buildings, Disposed | item     2      
Rentable Square Feet, Disposed | ft²     147,406      
Net Sales Proceeds     $ 25,552,000      
Net Carrying Value     18,456,000      
Realized Gains (losses)/Unrealized Losses, net     $ 7,096,000      
Disposal Group, Not Discontinued Operations [Member] | Flex Portfolio [Member]            
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]            
Number of Buildings, Disposed | item     56      
Rentable Square Feet, Disposed | ft²     3,148,512      
Net Sales Proceeds     $ 470,348,000      
Net Carrying Value     214,758,000      
Realized Gains (losses)/Unrealized Losses, net     $ 255,590,000      
Disposal Group, Not Discontinued Operations [Member] | 650 From Road [Member]            
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]            
Number of Buildings, Disposed | item     1      
Rentable Square Feet, Disposed | ft²     348,510      
Net Sales Proceeds     $ 37,801,000      
Net Carrying Value     40,046,000      
Realized Gains (losses)/Unrealized Losses, net     $ (2,245,000)      
Valuation allowance       $ 900,000    
Disposal Group, Not Discontinued Operations [Member] | 3600 Route 66 [Member]            
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]            
Number of Buildings, Disposed | item     1      
Rentable Square Feet, Disposed | ft²     180,000      
Net Sales Proceeds     $ 25,237,000      
Net Carrying Value     17,246,000      
Realized Gains (losses)/Unrealized Losses, net     $ 7,991,000      
Disposal Group, Not Discontinued Operations [Member] | Chase & Alterra Portfolio [Member]            
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]            
Number of Buildings, Disposed | item     3      
Rentable Square Feet, Disposed | ft²     1,386      
Net Sales Proceeds     $ 406,817,000      
Net Carrying Value     293,030,000      
Realized Gains (losses)/Unrealized Losses, net     113,787,000      
Carrying Amount of Mortgages     $ 235,800,000      
Disposal Group, Not Discontinued Operations [Member] | 5 Wood Hollow Road [Member]            
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]            
Number of Buildings, Disposed | item     1      
Rentable Square Feet, Disposed | ft²     317,040      
Net Sales Proceeds     $ 26,937,000      
Net Carrying Value     33,226,000      
Realized Gains (losses)/Unrealized Losses, net     $ (6,289,000)      
Impairment charge   $ 5,800,000        
Disposal Group, Not Discontinued Operations [Member] | Flex Portfolio [Member]            
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]            
Number of properties Disposed | property 2          
Redemption Of Common Units, Shares | shares 301,638   364,280      
Proceeds from sale of properties $ 6,600,000   $ 7,800,000      
Disposal Group, Not Discontinued Operations [Member] | Unsecured Revolving Credit Facility [Member]            
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]            
Carrying Amount of Mortgages     119,900,000      
Discontinued Operations [Member]            
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]            
Realized Gains (losses)/Unrealized Losses, net     1,702,000      
Unrealized losses on rental properties held for sale     (137,876,000)      
Totals     $ (136,174,000)      
Land [Member] | Disposal Group, Not Discontinued Operations [Member] | Hamilton Portfolio [Member]            
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]            
Number of properties Disposed | property         2