Segment Reporting (Schedule Of Reconciliation Of Net Operating Income To Net Income Available To Common Shareholders) (Details) - USD ($) |
3 Months Ended | 9 Months Ended | 12 Months Ended | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Dec. 31, 2020 |
Sep. 30, 2020 |
Jun. 30, 2020 |
Mar. 31, 2020 |
Dec. 31, 2019 |
Sep. 30, 2019 |
Jun. 30, 2019 |
Mar. 31, 2019 |
Sep. 30, 2020 |
Dec. 31, 2020 |
Dec. 31, 2019 |
Dec. 31, 2018 |
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| Segment Reporting Information [Line Items] | ||||||||||||
| Net operating income | $ 13,731,000 | $ 58,896,000 | $ 85,609,000 | |||||||||
| Depreciation and amortization | (122,035,000) | (133,597,000) | (113,817,000) | |||||||||
| Land and other impairments | (16,817,000) | (32,444,000) | (24,566,000) | |||||||||
| Property impairments | $ (36,600,000) | (36,582,000) | ||||||||||
| Gain on change of control of interests | 13,790,000 | 14,217,000 | ||||||||||
| Realized gains (losses) and unrealized losses on disposition of rental property, net | 5,481,000 | 343,102,000 | 99,436,000 | |||||||||
| Gain on disposition of developable land | 5,787,000 | 522,000 | 30,939,000 | |||||||||
| Gain on sale from unconsolidated joint ventures | 35,184,000 | 903,000 | ||||||||||
| Gain (loss) from extinguishment of debt, net | (272,000) | 1,648,000 | (8,994,000) | |||||||||
| Income (loss) from continuing operations | (115,523,000) | 252,820,000 | 82,824,000 | |||||||||
| Income from discontinued operations | 70,724,000 | 24,366,000 | 23,577,000 | |||||||||
| Loss from early extinguishment of debt | (1,757,000) | |||||||||||
| Realized gains (losses) and unrealized losses on disposition of rental property and impairments, net | 11,201,000 | (133,350,000) | ||||||||||
| Total discontinued operations, net | 81,925,000 | (108,984,000) | 23,577,000 | |||||||||
| Net income (loss) | $ 78,298,000 | $ (41,118,000) | $ (32,934,000) | $ (37,844,000) | $ (55,408,000) | $ (56,021,000) | $ (20,329,000) | $ 275,594,000 | (33,598,000) | 143,836,000 | 106,401,000 | |
| Noncontrolling interests in consolidated joint ventures | 2,695,000 | 3,904,000 | 1,216,000 | |||||||||
| Noncontrolling interests in Operating Partnership of income from continuing operations | 13,279,000 | (23,720,000) | (7,127,000) | |||||||||
| Noncontrolling interests in Operating Partnership in discontinued operations | (7,880,000) | 10,456,000 | (2,400,000) | |||||||||
| Redeemable noncontrolling interests | (25,883,000) | (22,615,000) | (13,979,000) | |||||||||
| Net income (loss) available to common shareholders | 65,632,000 | (42,208,000) | (34,887,000) | (39,924,000) | (54,652,000) | (55,928,000) | (22,054,000) | 244,495,000 | (51,387,000) | 111,861,000 | 84,111,000 | |
| Mack-Cali Realty LP [Member] | ||||||||||||
| Segment Reporting Information [Line Items] | ||||||||||||
| Net operating income | 13,731,000 | 58,896,000 | 85,609,000 | |||||||||
| Depreciation and amortization | (122,035,000) | (133,597,000) | (113,817,000) | |||||||||
| Land and other impairments | (16,817,000) | (32,444,000) | (24,566,000) | |||||||||
| Property impairments | (36,582,000) | |||||||||||
| Gain on change of control of interests | 13,790,000 | 14,217,000 | ||||||||||
| Realized gains (losses) and unrealized losses on disposition of rental property, net | 5,481,000 | 343,102,000 | 99,436,000 | |||||||||
| Gain on disposition of developable land | 5,787,000 | 522,000 | 30,939,000 | |||||||||
| Gain on sale from unconsolidated joint ventures | 35,184,000 | 903,000 | ||||||||||
| Gain (loss) from extinguishment of debt, net | (272,000) | 1,648,000 | (8,994,000) | |||||||||
| Income (loss) from continuing operations | (115,523,000) | 252,820,000 | 82,824,000 | |||||||||
| Income from discontinued operations | 70,724,000 | 24,366,000 | 23,577,000 | |||||||||
| Realized gains (losses) and unrealized losses on disposition of rental property and impairments, net | 11,201,000 | (133,350,000) | ||||||||||
| Total discontinued operations, net | 81,925,000 | (108,984,000) | 23,577,000 | |||||||||
| Net income (loss) | 78,298,000 | (41,118,000) | (32,934,000) | (37,844,000) | (55,408,000) | (56,021,000) | (20,329,000) | 275,594,000 | (33,598,000) | 143,836,000 | 106,401,000 | |
| Noncontrolling interests in consolidated joint ventures | 2,695,000 | 3,904,000 | 1,216,000 | |||||||||
| Redeemable noncontrolling interests | (25,883,000) | (22,615,000) | (13,979,000) | |||||||||
| Net income (loss) available to common shareholders | $ 72,623,000 | $ (46,694,000) | $ (38,576,000) | $ (44,139,000) | $ (60,475,000) | $ (62,087,000) | $ (24,488,000) | $ 272,175,000 | $ (56,786,000) | $ 125,125,000 | $ 93,638,000 | |
| X | ||||||||||
- Definition Discontinued Operation, Gains Losses On Extinguishment Of Debt No definition available.
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- Definition Gain (Loss) On Change Of Control Of Interests No definition available.
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- Definition Gain (Loss) On Sale Of Realized And Unrealized Property Plant Equipment No definition available.
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- Definition Impairment Of Land And Other No definition available.
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- Definition Amount of net income (loss) for the period allocated to noncontrolling partners in discontinued operations included in the entity's consolidated financial statements. No definition available.
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- Definition Noncontrolling Interest, Redemption Value Adjustment, Redeemable No definition available.
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- Definition Segment Reporting Information, Net Operating Income (Loss) For Reportable Segment No definition available.
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- Definition The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount after tax of gain (loss) not previously recognized resulting from the disposal of a discontinued operation. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount after tax of income (loss) from operations classified as a discontinued operation. Excludes gain (loss) on disposal and provision for gain (loss) until disposal. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The difference between the reacquisition price and the net carrying amount of the extinguished debt recognized currently as a component of income in the period of extinguishment, net of tax. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of gain (loss) on sale or disposal of property, plant and equipment assets, excluding oil and gas property and timber property. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition The net realized gain (loss) on investments sold during the period, not including gains (losses) on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity, which, for cash flow reporting, is a component of proceeds from investing activities. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The charge against earnings in the period to reduce the carrying amount of real property to fair value. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount after tax of income (loss) from continuing operations including portion attributable to the noncontrolling interest. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount after tax of income (loss) from a discontinued operation including the portion attributable to the noncontrolling interest. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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 Amount after tax of income (loss) attributable to nonredeemable noncontrolling shareholder, unit holder, partner, or other equity holder of a joint venture. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount after tax of income (loss) attributable to nonredeemable noncontrolling partner in an operating partnership. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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 Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Details
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