Condensed Quarterly Financial Information (Summary Of Condensed Quarterly Financial Information) (Details) - USD ($) |
3 Months Ended | 12 Months Ended | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
Dec. 31, 2019 |
Sep. 30, 2019 |
Jun. 30, 2019 |
Mar. 31, 2019 |
Dec. 31, 2018 |
Sep. 30, 2018 |
Jun. 30, 2018 |
Mar. 31, 2018 |
Dec. 31, 2019 |
Dec. 31, 2018 |
Dec. 31, 2017 |
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| Total revenues | $ 86,673,000 | $ 87,391,000 | $ 86,605,000 | $ 90,266,000 | $ 90,277,000 | $ 90,951,000 | $ 86,207,000 | $ 98,279,000 | $ 350,935,000 | $ 365,714,000 | $ 459,030,000 |
| Net income (loss) | (55,408,000) | (56,021,000) | (20,329,000) | 275,594,000 | 52,523,000 | 1,689,000 | 1,501,000 | 50,688,000 | 143,836,000 | 106,401,000 | 33,718,000 |
| Net income (loss) available to common shareholders | $ (54,652,000) | $ (55,928,000) | $ (22,054,000) | $ 244,495,000 | $ 43,804,000 | $ (1,478,000) | $ (1,251,000) | $ 43,036,000 | $ 111,861,000 | $ 84,111,000 | $ 23,185,000 |
| Basic earnings per common share: | |||||||||||
| Income from continuing operations | $ 0.53 | $ (0.64) | $ (0.45) | $ 2.59 | $ 0.37 | $ (0.12) | $ (0.13) | $ 0.42 | $ 2.03 | $ 0.54 | $ (0.17) |
| Discontinued operations | (1.17) | (0.01) | 0.02 | 0.08 | 0.08 | 0.07 | 0.08 | 0.03 | (1.08) | 0.26 | 0.23 |
| Net income available to common unitholders | (0.64) | (0.65) | (0.43) | 2.67 | 0.45 | (0.05) | (0.05) | 0.45 | 0.95 | 0.80 | 0.06 |
| Diluted earnings per common share: | |||||||||||
| Income from continuing operations | 0.53 | (0.64) | (0.45) | 2.58 | 0.37 | (0.12) | (0.13) | 0.42 | 2.03 | 0.54 | (0.17) |
| Discontinued operations | (1.17) | (0.01) | 0.02 | 0.08 | 0.08 | 0.07 | 0.08 | 0.03 | (1.08) | 0.26 | 0.23 |
| Net income (loss) available to common shareholders | $ (0.64) | $ (0.65) | $ (0.43) | $ 2.66 | $ 0.45 | $ (0.05) | $ (0.05) | $ 0.45 | $ 0.95 | $ 0.80 | $ 0.06 |
| Mack-Cali Realty LP [Member] | |||||||||||
| Total revenues | $ 86,673,000 | $ 87,391,000 | $ 86,605,000 | $ 90,266,000 | $ 90,277,000 | $ 90,951,000 | $ 86,207,000 | $ 98,279,000 | $ 350,935,000 | $ 365,714,000 | $ 459,030,000 |
| Net income (loss) | (55,408,000) | (56,021,000) | (20,329,000) | 275,594,000 | 52,523,000 | 1,689,000 | 1,501,000 | 50,688,000 | 143,836,000 | 106,401,000 | 33,718,000 |
| Net income (loss) available to common shareholders | $ (60,475,000) | $ (62,087,000) | $ (24,488,000) | $ 272,175,000 | $ 48,757,000 | $ (1,645,000) | $ (1,393,000) | $ 47,919,000 | $ 125,125,000 | $ 93,638,000 | $ 25,896,000 |
| Basic earnings per common share: | |||||||||||
| Income from continuing operations | $ 0.53 | $ (0.64) | $ (0.45) | $ 2.59 | $ 0.37 | $ (0.12) | $ (0.13) | $ 0.42 | $ 2.03 | $ 0.54 | $ (0.17) |
| Discontinued operations | (1.17) | (0.01) | 0.02 | 0.08 | 0.08 | 0.07 | 0.08 | 0.03 | (1.08) | 0.26 | 0.23 |
| Net income available to common unitholders | (0.64) | (0.65) | (0.43) | 2.67 | 0.45 | (0.05) | (0.05) | 0.45 | 0.95 | 0.80 | 0.06 |
| Diluted earnings per common share: | |||||||||||
| Income from continuing operations | 0.53 | (0.64) | (0.45) | 2.58 | 0.37 | (0.12) | (0.13) | 0.42 | 2.03 | 0.54 | (0.17) |
| Discontinued operations | (1.17) | (0.01) | 0.02 | 0.08 | 0.08 | 0.07 | 0.08 | 0.03 | (1.08) | 0.26 | 0.23 |
| Net income (loss) available to common shareholders | $ (0.64) | $ (0.65) | $ (0.43) | $ 2.66 | $ 0.45 | $ (0.05) | $ (0.05) | $ 0.45 | $ 0.95 | $ 0.80 | $ 0.06 |
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- Definition The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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- Definition The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- References No definition available.
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- Definition The amount of net income (loss) from continuing operations per each share of common stock or unit outstanding during the reporting period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The amount of net income (loss) derived from continuing operations during the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Per basic share amount, after tax, of income (loss) from the day-to-day business activities of the discontinued operation and gain (loss) from the disposal of the discontinued operation. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Per diluted share amount, after tax, of income (loss) from the day-to-day business activities of the discontinued operation and gain (loss) from the disposal of the discontinued operation. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The portion of profit or loss for the period, net of income taxes, which is attributable to the parent. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Details
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