Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands |
Dec. 31, 2018 |
Dec. 31, 2017 |
|---|---|---|
| Allowance for doubtful accounts receivable | $ 1,108 | $ 1,138 |
| Common stock, par value per share | $ 0.01 | $ 0.01 |
| Common stock, shares authorized | 190,000,000 | 190,000,000 |
| Common stock, shares outstanding | 90,320,306 | 89,914,113 |
| Mack-Cali Realty LP [Member] | ||
| Allowance for doubtful accounts receivable | $ 1,108 | $ 1,138 |
| General partner common units outstanding | 90,320,306 | 89,914,113 |
| Limited partners common units outstanding | 10,174,285 | 10,438,855 |