Quarterly report pursuant to Section 13 or 15(d)

Mack-Cali Realty Corporation Stockholders' Equity And Mack-Cali Realty, L.P.'s Partners' Capital (Long-Term Incentive Plan Awards) (Narrative) (Details)

v3.21.1
Mack-Cali Realty Corporation Stockholders' Equity And Mack-Cali Realty, L.P.'s Partners' Capital (Long-Term Incentive Plan Awards) (Narrative) (Details)
$ / shares in Units, $ in Millions
3 Months Ended
Apr. 21, 2021
item
shares
Nov. 03, 2020
Mar. 22, 2019
Apr. 20, 2018
Jun. 05, 2015
item
$ / shares
shares
Mar. 31, 2021
USD ($)
shares
Dec. 31, 2023
$ / shares
Apr. 19, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Performance period           3 years    
Shares granted         800,000      
Annual installments | item         3      
Share price | $ / shares         $ 17.31      
2016 LTIP Awards [Member]                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Dividends paid, percent representing common unit of limited partnership interest           10.00%    
Dividends paid, percent payable upon vesting of LTIP Unit           90.00%    
Unvested LTIP [Member]                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Total unrecognized compensation cost | $           $ 10.2    
Total unrecognized compensation cost, period of recognition           2 years 1 month 6 days    
2018 OPP [Member]                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Performance period           3 years    
TSR percent           36.00%    
2019 OPP [Member]                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Performance period           3 years    
TSR percent           36.00%    
2020 OPP [Member]                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Performance period           3 years    
TSR percent           36.00%    
2021 RSU LTIP Awards [Member]                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Performance period           3 years    
Subsequent Event [Member]                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Percentage of units forfeited               31.25%
Subsequent Event [Member] | 2021 RSU LTIP Awards [Member] | Time-Based Award [Member]                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Shares granted 291,951              
Annual installments | item 3              
Exercisable time period 3 years              
Subsequent Event [Member] | 2021 RSU LTIP Awards [Member] | Performance Shares [Member]                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Performance period 3 years              
TSR percent 36.00%              
Shares granted 452,730              
Other Executive Officers [Member] | 2018 LTIP Awards [Member]                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Percent of the award       50.00%        
Remaining percent of the award       50.00%        
Messieur DeMarco And Messieur Tycher [Member] | 2018 LTIP Awards [Member] | Time-Based Award [Member]                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Percent of the award       25.00%        
Performance period           3 years    
Messieur DeMarco And Messieur Tycher [Member] | 2018 LTIP Awards [Member] | Performance Shares [Member]                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Remaining percent of the award       75.00%        
Messr DeMarco, CEO [Member] | 2019 LTIP Awards [Member] | Time-Based Award [Member]                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Percent of the award     25.00%          
Messr DeMarco, CEO [Member] | 2019 LTIP Awards [Member] | Performance Shares [Member]                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Remaining percent of the award     75.00%          
Messr DeMarco, CEO [Member] | 2019 TBV LTIP Units [Member] | Time-Based Award [Member]                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Performance period           3 years    
Messieur Tycher, Smetana, Wagner, Cardoso, And Hilton [Member] | 2019 LTIP Awards [Member]                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Percent of the award     50.00%          
Remaining percent of the award     50.00%          
Messr DeBari [Member] | 2019 LTIP Awards [Member]                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Percent of the award           100.00%    
Ricardo Cardoso [Member] | J Series 2021 OPP [Member]                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Percent of estimated net asset   85.00%            
Maximum [Member] | Outperformance RSUs [Member]                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Shares granted           291,951    
Scenario, Forecast [Member] | Outperformance RSUs [Member]                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Share price | $ / shares             $ 0.60