Quarterly report pursuant to Section 13 or 15(d)

Recent Transactions (Consolidation) (Narrative) (Details)

v3.19.1
Recent Transactions (Consolidation) (Narrative) (Details)
3 Months Ended
Jan. 31, 2019
USD ($)
item
Jan. 30, 2019
USD ($)
Mar. 31, 2019
USD ($)
item
Mar. 31, 2018
USD ($)
Dec. 31, 2018
USD ($)
Real Estate Properties [Line Items]          
Percentage of ownership interest     90.00%   89.80%
Purchase price of property     $ 43,307,000 $ 55,935,000  
Gain on change of control of interests     13,790,000    
Issuance of loan     43,300,000    
Loan balance     2,686,317,000   $ 2,792,651,000
Noncontrolling interest's fair value     239,149,000   $ 210,523,000
Mack-Cali Realty LP [Member]          
Real Estate Properties [Line Items]          
Purchase price of property     43,307,000 $ 55,935,000  
Gain on change of control of interests     $ 13,790,000    
Unconsolidated Joint Venture Multi-Family Properties [Member]          
Real Estate Properties [Line Items]          
Number of units | item     2,611    
Unconsolidated Joint Venture Multi-Family Properties [Member] | Marbella Tower Urban Renewal Associates LLC [Member]          
Real Estate Properties [Line Items]          
Percentage of interest in venture   24.27%      
Percentage of additional interest acquired 50.00% 50.00%      
Number of units | item 311        
Purchase price of property $ 77,500,000        
Mortgage loan, maturity date     Aug. 01, 2026    
Spread over LIBOR 4.20%        
Mortgage loan $ 117,000,000 $ 74,700,000      
Gain on change of control of interests     $ 13,800,000    
Repayment of mortgage loans $ 74,700,000        
Loan balance     15,300,000    
Noncontrolling interest's fair value     $ 13,700,000