Mack-Cali Realty Corporation Stockholders' Equity And Mack-Cali Realty, L.P.'s Partners' Capital (Earnings Per Share/Unit) (Narrative) (Details) - $ / shares |
3 Months Ended | ||
|---|---|---|---|
Mar. 31, 2018 |
Mar. 31, 2017 |
Dec. 31, 2017 |
|
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||
| Unvested restricted stock outstanding | 74,413 | 108,318 | |
| Dividends declared per common share | $ 0.20 | $ 0.15 | |
| Mack-Cali Realty LP [Member] | |||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||
| Dividends declared per common share | $ 0.20 | $ 0.15 | |
| Unvested Restricted Stock [Member] | |||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||
| Unvested restricted stock outstanding | 61,896 | 37,752 | |
| Unvested Restricted Stock [Member] | Mack-Cali Realty LP [Member] | |||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||
| Unvested restricted stock outstanding | 61,896 | 37,752 | |