Segment Reporting (Schedule Of Reconciliation Of Net Operating Income To Net Income Available To Common Shareholders) (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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| Segment Reporting Information [Line Items] | |||||||||||
| Net operating income | $ 54,225,000 | $ 81,414,000 | $ 128,085,000 | ||||||||
| Depreciation and amortization | (132,016,000) | (112,244,000) | (142,319,000) | ||||||||
| Land impairment | (32,444,000) | (24,566,000) | |||||||||
| 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 | 345,926,000 | 99,436,000 | 2,364,000 | ||||||||
| Gain on disposition of developable land | 522,000 | 30,939,000 | |||||||||
| Gain on sale of investment in unconsolidated joint venture | 903,000 | 23,131,000 | |||||||||
| Gain (loss) from extinguishment of debt, net | 1,648,000 | (8,929,000) | (421,000) | ||||||||
| Income from continuing operations | 252,554,000 | 80,267,000 | 10,840,000 | ||||||||
| Income from discontinued operations | 27,456,000 | 26,134,000 | 22,878,000 | ||||||||
| Loss from early extinguishment of debt | (1,821,000) | ||||||||||
| Realized gains (losses) and unrealized losses on disposition of rental property and impairments, net | (136,174,000) | ||||||||||
| Total discontinued operations, net | (108,718,000) | 26,134,000 | 22,878,000 | ||||||||
| Net income | $ (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 |
| Noncontrolling interests in consolidated joint ventures | 3,904,000 | 1,216,000 | 1,018,000 | ||||||||
| Noncontrolling interests in Operating Partnership of income from continuing operations | (23,685,000) | (6,866,000) | (341,000) | ||||||||
| Noncontrolling interest in discontinued operations | (10,421,000) | 2,661,000 | 2,370,000 | ||||||||
| Redeemable noncontrolling interests | (22,615,000) | (13,979,000) | (8,840,000) | ||||||||
| Net income 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 |
| Mack-Cali Realty LP [Member] | |||||||||||
| Segment Reporting Information [Line Items] | |||||||||||
| Net operating income | 54,225,000 | 81,414,000 | 128,085,000 | ||||||||
| Depreciation and amortization | (132,016,000) | (112,244,000) | (142,319,000) | ||||||||
| Land impairment | (32,444,000) | (24,566,000) | |||||||||
| 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 | 345,926,000 | 99,436,000 | 2,364,000 | ||||||||
| Gain on disposition of developable land | 522,000 | 30,939,000 | |||||||||
| Gain on sale of investment in unconsolidated joint venture | 903,000 | 23,131,000 | |||||||||
| Gain (loss) from extinguishment of debt, net | 1,648,000 | (8,929,000) | (421,000) | ||||||||
| Income from continuing operations | 252,554,000 | 80,267,000 | 10,840,000 | ||||||||
| Income from discontinued operations | 27,456,000 | 26,134,000 | 22,878,000 | ||||||||
| Realized gains (losses) and unrealized losses on disposition of rental property and impairments, net | (136,174,000) | ||||||||||
| Total discontinued operations, net | (108,718,000) | 26,134,000 | 22,878,000 | ||||||||
| Net income | (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 |
| Noncontrolling interests in consolidated joint ventures | 3,904,000 | 1,216,000 | 1,018,000 | ||||||||
| Redeemable noncontrolling interests | (22,615,000) | (13,979,000) | (8,840,000) | ||||||||
| Net income 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 |
| 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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| X | ||||||||||
- 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 Amount after tax of income (loss) from continuing operations including portion attributable to the noncontrolling interest. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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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