Quarterly report pursuant to Section 13 or 15(d)

Mack-Cali Realty Corporation Stockholders' Equity And Mack-Cali Realty, L.P.'s Partners' Capital (AO LTIP Units (Appreciation-Only LTIP Units)) (Narrative) (Details)

v3.20.2
Mack-Cali Realty Corporation Stockholders' Equity And Mack-Cali Realty, L.P.'s Partners' Capital (AO LTIP Units (Appreciation-Only LTIP Units)) (Narrative) (Details) - USD ($)
3 Months Ended 6 Months Ended
Jun. 05, 2015
Jun. 30, 2020
Jun. 30, 2019
Mar. 31, 2019
Jun. 30, 2020
Jun. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Shares granted 800,000          
Share price $ 17.31          
Exercisable period         10 years  
Common stock trading days         30 days  
Common stock trade share price $ 25.00          
Stock options expense   $ 0 $ 0   $ 0 $ 0
AO LTIP Units Award [Member]            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Share price   $ 21.46     $ 21.46  
Exercisable period         10 years  
Share price - weighted average fair value of options granted           $ 3.98
Total unrecognized compensation cost   $ 1,700,000     $ 1,700,000  
Total unrecognized compensation cost, period of recognition         2 years 8 months 12 days  
Stock options expense   $ 155,000 $ 155,000   $ 310,000 $ 187,000
AO LTIP Units Award [Member] | Messr DeMarco, CEO [Member]            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Shares granted       625,000 625,000  
Income allocation         10.00%  
Percent of cash distribution         10.00%  
AO LTIP Units Award [Member] | Messr DeMarco, CEO [Member] | Tranche One [Member]            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Shares to be vested and exercisable         250,000  
Common stock trading days         30 days  
Common stock trade share price         $ 25.00  
Common stock expiration date         Mar. 13, 2023  
AO LTIP Units Award [Member] | Messr DeMarco, CEO [Member] | Tranche Two [Member]            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Shares to be vested and exercisable         250,000  
Common stock trading days         30 days  
Common stock trade share price         $ 28.00  
AO LTIP Units Award [Member] | Messr DeMarco, CEO [Member] | Tranche Three [Member]            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Shares to be vested and exercisable         125,000  
Common stock trading days         30 days  
Common stock trade share price         $ 31.00