Quarterly report pursuant to Section 13 or 15(d)

Redeemable Noncontrolling Interests (Narrative) (Details)

v3.19.3
Redeemable Noncontrolling Interests (Narrative) (Details)
3 Months Ended 9 Months Ended 12 Months Ended
Jun. 30, 2019
USD ($)
Jun. 26, 2019
USD ($)
property
Mar. 10, 2017
USD ($)
Feb. 28, 2017
USD ($)
$ / shares
shares
Feb. 27, 2017
USD ($)
Feb. 03, 2017
USD ($)
$ / shares
shares
Sep. 30, 2019
USD ($)
Jun. 30, 2019
Mar. 31, 2019
USD ($)
Sep. 30, 2018
USD ($)
Sep. 30, 2019
USD ($)
Sep. 30, 2018
USD ($)
Dec. 31, 2018
USD ($)
Apr. 30, 2017
shares
Redeemable Noncontrolling Interest [Line Items]                            
General and administrative             $ 12,054,000     $ 11,620,000 $ 41,074,000 $ 41,160,000    
Expiration period                     10 years      
Minimum [Member]                            
Redeemable Noncontrolling Interest [Line Items]                            
Percentage of interest in venture             20.00%       20.00%      
Maximum [Member]                            
Redeemable Noncontrolling Interest [Line Items]                            
Percentage of interest in venture             85.00%       85.00%      
Mack-Cali Realty LP [Member]                            
Redeemable Noncontrolling Interest [Line Items]                            
General and administrative             $ 12,054,000     $ 11,620,000 $ 41,074,000 $ 41,160,000    
Rockpoint [Member]                            
Redeemable Noncontrolling Interest [Line Items]                            
Estimated redemption value                     491,000,000      
Rockpoint [Member] | Cash Flow From Operations [Member]                            
Redeemable Noncontrolling Interest [Line Items]                            
Invested capital             400,000,000       400,000,000      
Rockpoint [Member] | Cash Flow From Capital Events, Distribution Five [Member]                            
Redeemable Noncontrolling Interest [Line Items]                            
Invested capital             400,000,000       400,000,000      
Rockpoint [Member] | Cash Flow From Capital Events, Distribution Six [Member]                            
Redeemable Noncontrolling Interest [Line Items]                            
Invested capital             400,000,000       $ 400,000,000      
Rockpoint [Member] | Distribution One [Member]                            
Redeemable Noncontrolling Interest [Line Items]                            
Purchase price   $ 173,500,000                        
Purchase price, less distributions   198,500,000                        
Rockpoint [Member] | Distribution Two [Member]                            
Redeemable Noncontrolling Interest [Line Items]                            
Purchase price, less distributions   1,500,000                        
Series A Units [Member] | Mack-Cali Realty LP [Member]                            
Redeemable Noncontrolling Interest [Line Items]                            
Preferred units shares issued | shares           42,800                
Preferred unit annual rate           3.50%                
Percentage of interest in venture           37.50%                
Preferred unit in operating partnership           $ 1,000                
Convertible preferred units | shares           28.15                
Expiration period           5 years                
Shares that may be converted to common units | shares           1,204,820                
Common unit distribution per unit declared | $ / shares           $ 35.52                
Series A-1 Units [Member] | Mack-Cali Realty LP [Member]                            
Redeemable Noncontrolling Interest [Line Items]                            
Preferred units shares issued | shares       9,213                   91
Preferred unit annual rate       3.50%                    
Percentage of interest in venture       13.80%                    
Preferred unit in operating partnership       $ 1,000                    
Convertible preferred units | shares       27.936                    
Expiration period       5 years             5 years      
Shares that may be converted to common units | shares       257,375                    
Common unit distribution per unit declared | $ / shares       $ 35.80                    
Preferred Units [Member] | Rockpoint [Member]                            
Redeemable Noncontrolling Interest [Line Items]                            
Pro rata distribution                     10.947%      
Preferred Units [Member] | Rockpoint [Member] | Cash Flow From Operations [Member]                            
Redeemable Noncontrolling Interest [Line Items]                            
Pro rata distribution                     21.89%      
Preferred Units [Member] | Rockpoint [Member] | Cash Flow From Capital Events, Distribution Five [Member]                            
Redeemable Noncontrolling Interest [Line Items]                            
Pro rata distribution                     21.89%      
Preferred Units [Member] | RRT [Member] | Cash Flow From Operations [Member]                            
Redeemable Noncontrolling Interest [Line Items]                            
Pro rata distribution                     2.65%      
Preferred Units [Member] | RRT [Member] | Cash Flow From Capital Events, Distribution Five [Member]                            
Redeemable Noncontrolling Interest [Line Items]                            
Pro rata distribution                     2.65%      
Preferred Units [Member] | RRT [Member] | Cash Flow From Capital Events, Distribution Six [Member]                            
Redeemable Noncontrolling Interest [Line Items]                            
Pro rata distribution                     1.325%      
Monaco [Member] | Series A-1 Units [Member] | Mack-Cali Realty LP [Member]                            
Redeemable Noncontrolling Interest [Line Items]                            
Preferred units shares issued | shares       9,122                    
Common Units [Member] | RRT [Member] | Cash Flow From Operations [Member]                            
Redeemable Noncontrolling Interest [Line Items]                            
Pro rata distribution                     75.46%      
Common Units [Member] | RRT [Member] | Cash Flow From Capital Events, Distribution Five [Member]                            
Redeemable Noncontrolling Interest [Line Items]                            
Pro rata distribution                     75.46%      
Common Units [Member] | RRT [Member] | Cash Flow From Capital Events, Distribution Six [Member]                            
Redeemable Noncontrolling Interest [Line Items]                            
Pro rata distribution                     87.728%      
Investment Agreement [Member] | Rockpoint [Member]                            
Redeemable Noncontrolling Interest [Line Items]                            
Contributed equity value     $ 1,230,000,000                      
Incremental closing payments, Limited Partnership interest   46,000,000 $ 150,000,000           $ 45,000,000       $ 105,000,000  
Investment Agreement [Member] | Rockpoint [Member] | Minimum [Member]                            
Redeemable Noncontrolling Interest [Line Items]                            
Incremental closing payments, Limited Partnership interest                         $ 105,000,000  
Investment Agreement [Member] | Rockpoint [Member] | Maximum [Member]                            
Redeemable Noncontrolling Interest [Line Items]                            
Contributed amount to obtain equity units         $ 300,000,000                  
Contributed amount to obtain equity units         $ 300,000,000       $ 300,000,000          
Add On Investment Agreement [Member] | Rockpoint [Member]                            
Redeemable Noncontrolling Interest [Line Items]                            
Contributed amount to obtain equity units   $ 100,000,000                        
Number of properties in which additional interest was acquired during period | property   2                        
Right of first refusal to invest $ 100,000,000                          
General and administrative             371,000,000,000       $ 371,000,000,000      
Add On Investment Agreement [Member] | Rockpoint [Member] | Maximum [Member]                            
Redeemable Noncontrolling Interest [Line Items]                            
Contributed amount to obtain equity units $ 154,000,000                          
RRLP [Member] | Cash Flow From Operations [Member]                            
Redeemable Noncontrolling Interest [Line Items]                            
Annual return on the equity value                     6.00%      
RRLP [Member] | Rockpoint [Member] | Cash Flow From Operations [Member]                            
Redeemable Noncontrolling Interest [Line Items]                            
Annual return                     6.00%      
Base return                     4.64%      
RRLP [Member] | Rockpoint [Member] | Cash Flow From Capital Events, Distribution Three [Member]                            
Redeemable Noncontrolling Interest [Line Items]                            
Base return                     4.64%      
RRLP [Member] | Rockpoint [Member] | Cash Flow From Capital Events, Distribution Four [Member]                            
Redeemable Noncontrolling Interest [Line Items]                            
Capital base return                     4.64%      
RRLP [Member] | Rockpoint [Member] | Cash Flow From Capital Events, Distribution Six [Member]                            
Redeemable Noncontrolling Interest [Line Items]                            
Pro rata share                     50.00%      
RRLP [Member] | RRT [Member]                            
Redeemable Noncontrolling Interest [Line Items]                            
Loan-to-value ratio   65.00%                        
Equity capitalization percent                     10.00%      
RRLP [Member] | RRT [Member] | Cash Flow From Operations [Member]                            
Redeemable Noncontrolling Interest [Line Items]                            
Base return                     95.36%      
RRLP [Member] | RRT [Member] | Cash Flow From Capital Events, Distribution Three [Member]                            
Redeemable Noncontrolling Interest [Line Items]                            
Base return                     95.36%      
RRLP [Member] | RRT [Member] | Cash Flow From Capital Events, Distribution Four [Member]                            
Redeemable Noncontrolling Interest [Line Items]                            
Capital base return                     95.36%      
RRLP [Member] | Investment Agreement [Member] | Rockpoint [Member] | Cash Flow From Operations [Member]                            
Redeemable Noncontrolling Interest [Line Items]                            
Base return               5.00%            
RRLP [Member] | Investment Agreement [Member] | Rockpoint [Member] | Cash Flow From Capital Events, Distribution Three [Member]                            
Redeemable Noncontrolling Interest [Line Items]                            
Base return               95.00%            
RRLP [Member] | Investment Agreement [Member] | Rockpoint [Member] | Cash Flow From Capital Events, Distribution Four [Member]                            
Redeemable Noncontrolling Interest [Line Items]                            
Capital base return               5.00%            
RRLP [Member] | Investment Agreement [Member] | RRT [Member] | Cash Flow From Operations [Member]                            
Redeemable Noncontrolling Interest [Line Items]                            
Base return               95.00%            
RRLP [Member] | Investment Agreement [Member] | RRT [Member] | Cash Flow From Capital Events, Distribution Three [Member]                            
Redeemable Noncontrolling Interest [Line Items]                            
Base return               5.00%            
RRLP [Member] | Investment Agreement [Member] | RRT [Member] | Cash Flow From Capital Events, Distribution Four [Member]                            
Redeemable Noncontrolling Interest [Line Items]                            
Capital base return               95.00%            
RRLP [Member] | Credit Enhancement Note [Member]                            
Redeemable Noncontrolling Interest [Line Items]                            
Maximum borrowing capacity             50,000,000       $ 50,000,000      
Increased line of credit             $ 25,000,000       $ 25,000,000