Quarterly report pursuant to Section 13 or 15(d)

Noncontrolling Interests In Subsidiaries (Narrative) (Details)

v3.20.2
Noncontrolling Interests In Subsidiaries (Narrative) (Details)
$ in Millions
 3 Months Ended 6 Months Ended
Jun. 05, 2015
shares
Mar. 31, 2019
shares
Jun. 30, 2020
USD ($)
property
shares
Dec. 31, 2019
Noncontrolling Interest [Line Items]        
Number of common shares received upon redemption of common units     1  
Rebalance of ownership percentage | $     $ 2.4  
Shares granted 800,000      
Exercisable period     10 years  
Participation Rights [Member]        
Noncontrolling Interest [Line Items]        
Number of properties | property     1  
Excess net cash flow remaining after the distribution to the Company     50.00%  
Internal rate of return     10.00%  
Mack-Cali Realty LP [Member]        
Noncontrolling Interest [Line Items]        
Percentage of noncontrolling interest     9.60% 9.60%
Future Developments [Member] | Participation Rights [Member]        
Noncontrolling Interest [Line Items]        
Number of properties | property     1  
Disposal Group, Not Discontinued Operations [Member] | Flex Portfolio [Member]        
Noncontrolling Interest [Line Items]        
Proceeds from sale of properties | $     $ 2.1  
Redemption of common units, shares     97,727  
AO LTIP Units Award [Member]        
Noncontrolling Interest [Line Items]        
Exercisable period     10 years  
AO LTIP Units Award [Member] | Messr DeMarco, CEO [Member]        
Noncontrolling Interest [Line Items]        
Shares granted   625,000 625,000