Consolidated Balance Sheets (Parenthetical) - $ / shares |
Sep. 30, 2021 |
Dec. 31, 2020 |
|---|---|---|
| Common stock, par value per share | $ 0.01 | $ 0.01 |
| Common stock, shares authorized | 190,000,000 | 190,000,000 |
| Common stock, shares outstanding | 90,947,387 | 90,712,417 |
| Mack-Cali Realty LP [Member] | ||
| General Partner common units outstanding | 90,947,387 | 90,712,417 |
| Limited partners common units outstanding | 9,021,400 | 9,649,031 |