Document and Entity Information [Abstract] Document And Entity Information [Abstract] Statement [Table] Statement [Line Items] Entity Registrant Name Document Type Amendment Flag Document Period End Date Entity Central Index Key Current Fiscal Year End Date Entity Filer Category Document Fiscal Year Focus Document Fiscal Period Focus Entity Common Stock, Shares Outstanding Consolidated Balance Sheets [Abstract] ASSETS Rental Property [Abstract] Rental Property [Abstract] Rental property Land and leasehold interests Buildings and improvements Tenant improvements Furniture, fixtures and equipment Gross investment in rental property Gross investment in rental property Less - accumulated depreciation and amortization Less - accumulated depreciation and amortization Net investment in rental property Total investment in rental property Assets Held-for-sale, Property, Plant and Equipment Rental property held for sale, net Net Investment In Rental Property And Rental Property Held For Sale Net Investment In Rental Property And Rental Property Held For Sale Net investment in rental property Cash and cash equivalents, beginning of period Cash and cash equivalents, end of period Cash and cash equivalents, beginning of period Cash and cash equivalents Company's investments in unconsolidated joint ventures Investments in unconsolidated joint ventures Unbilled rents receivable, net Deferred charges, goodwill and other assets Total deferred charges, goodwill and other assets Restricted Cash And Cash Equivalents Total restricted cash Restricted cash Accounts Receivable Net Accounts receivable, net of allowance for doubtful accounts of $3,122 and $2,614 Total assets Total assets LIABILITIES AND EQUITY Unsecured Debt Senior Unsecured Notes Senior unsecured notes Secured Debt Mortgages, loans payable and other obligations Mortgage loan Dividends and distributions payable Accounts payable, accrued expenses and other liabilities Amount at the balance sheet date including both: (a) rents and other amounts paid in advance by tenants and clients; and (b) security deposits paid in advance to protect the provider of a service, such as a lessor, against damage or nonpayment by the tenant (lessee) during the term of the agreement. Such damages may include physical damage to the property, theft of property, and other contractual breaches. Rents received in advance and security deposits Accrued interest payable Total liabilities Total liabilities Commitments And Contingencies 2009 Commitments and contingencies Equity: Stockholders' Equity Attributable to Parent [Abstract] Mack-Cali Realty Corporation stockholders' equity: Common stock value Common stock, $0.01 par value, 190,000,000 shares authorized, 88,021,807 and 87,536,292 shares outstanding Additional Paid In Capital Additional paid-in capital Retained Earnings Accumulated Deficit Dividends in excess of net earnings Stockholders' Equity Attributable to Parent Total Mack-Cali Realty Corporation stockholders' equity Noncontrolling Interest Items [Abstract] Noncontrolling interests in subsidiaries: Operating Partnership Minority Interest In Joint Ventures Consolidated joint ventures Total noncontrolling interests in subsidiaries Total noncontrolling interests in subsidiaries Total equity Balance, value Balance, value Total equity Liabilities And Stockholders Equity Total liabilities and equity Allowance for doubtful accounts receivable Allowance for doubtful accounts receivable Common stock, par value per share Common stock, shares authorized Common Stock Shares Outstanding Common stock, shares outstanding Consolidated Statements Of Operations [Abstract] Revenues Abstract REVENUES Base rents Escalations and recoveries from tenants Construction services Other Real Estate Revenue Real estate services Parking Revenue Parking income Other income Real Estate Revenue, Net Total revenues Total revenues EXPENSES Real estate taxes Utilities Operating services Direct construction costs The aggregate costs including administrative paperwork, real estate brokerage, title, and property management operations. Costs Of Real Estate Services Real estate services expenses Closing costs General and administrative Depreciation and amortization Depreciation and amortization Impairment charge Impairments Impairments Costs and Expenses Total expenses Operating income Operating income OTHER (EXPENSE) INCOME Interest expense Interest expense Interest and other investment income Equity in earnings (loss) of unconsolidated joint ventures Equity in loss (earnings) of unconsolidated joint venture, net Company's equity in earnings of unconsolidated joint ventures Gains (Losses) on Extinguishment of Debt Loss from early extinguishment of debt Nonoperating Income (Expense) Total other (expense) income Income from continuing operations Income (loss) from continuing operations Income (loss) from continuing operations Discontinued Operations [Abstract] Discontinued operations: Income (loss) from discontinued operations for diluted earnings per share Income from discontinued operations Income from discontinued operations Discontinued Operation, Gains Losses On Extinguishment Of Debt Discontinued Operation, Gains Losses On Extinguishment Of Debt Loss from early extinguishment of debt Loss from early extinguishment of debt Realized (gains) and unrealized losses on disposition of rental proeprty, net Realized (gains) and unrealized losses on disposition of rental property and impairments, net Realized gains (losses) and unrealized losses on disposition of rental property and impairments, net Realized gains (losses) and unrealized losses on disposition of rental property and impairments, net Income (Loss) from Discontinued Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest Total discontinued operations, net Income from discontinued operations for diluted earnings per share Net income Net income Noncontrolling interest in consolidated joint ventures Add: Noncontrolling interest in consolidated joint ventures Noncontrolling interest in consolidated joint ventures Noncontrolling interest in operating partnership Noncontrolling interest in Operating Partnership Deduct: Noncontrolling interest in Operating Partnership Add: Noncontrolling interest in Operating Partnership Amount of net income (loss) for the period allocated to noncontrolling partners in discontinued operations included in the entity's consolidated financial statements. Noncontrolling interest in discontinued operations Noncontrolling interest in discontinued operations Net income (loss) available to common shareholders Net income available to common shareholders Net income available to common shareholders Basic earnings per common share: Income (loss) from continuing operations available to common shareholders Income (loss) from continuing operations Income (Loss) from Discontinued Operations, Net of Tax, Per Basic Share Discontinued operations Income from discontinued operations available to common shareholders Net income available to common shareholders Net income available to common shareholders Diluted earnings per common share: Income Loss From Continuing Operations Per Diluted Share Income (loss) from continuing operations Income (loss) from continuing operations available to common shareholders Income (Loss) from Discontinued Operations, Net of Tax, Per Diluted Share Discontinued operations Income from discontinued operations available to common shareholders Earnings Per Share Diluted Net income available to common shareholders Basic weighted average shares outstanding Basic EPS shares Weighted average common shares Diluted weighted average shares outstanding Weighted average common shares Diluted EPS Shares Consolidated Statement Of Changes In Equity [Abstract] Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Common Stock [Member] Common Stock [Member] Additional Paid In Capital [Member] Additional Paid-In Capital [Member] Retained Earnings [Member] Dividends In Excess Of Net Earnings [Member] Noncontrolling Interest [Member] Noncontrolling Interests In Subsidiaries [Member] Shares, Issued Balance, shares Balance, shares Common stock dividends Common stock dividends Common unit distributions Common unit distributions Increase in noncontrolling interest Increase in noncontrolling interest Redemption of common units for common stock, value Redemption of common units for common stock, value Redemption of common units for common stock, shares Shares issued under Dividend Reinvestment and Stock Purchase Plan, value Shares issued under Dividend Reinvestment and Stock Purchase Plan, shares Stock Compensation, value Stock compensation, value Stock Issued During Period, Shares, Share-based Compensation, Net of Forfeitures Stock compensation, shares Rebalancing of ownership percentage between parent and subsidiaries Consolidated Statements Of Cash Flows [Abstract] CASH FLOWS FROM OPERATING ACTIVITIES Adjustments to reconcile net income to net cash provided by Operating activities: Depreciation and amortization, including related intangible assets Depreciation Amortization On Discontinued Operations Depreciation Amortization On Discontinued Operations Depreciation and amortization Depreciation and amortization on discontinued operations Stock compensation Amortization of stock compensation Amortization of deferred financing costs and debt discount Write off of Deferred Debt Issuance Cost Write off of unamortized discount on senior unsecured notes Write off of unamortized deferred financing costs Equity Method Investment Dividends Or Distributions Distributions of cumulative earnings from unconsolidated joint ventures Changes in operating assets and liabilities: Increase Decrease In Unbilled Rent Receivables Increase Decrease In Unbilled Rent Receivables Increase in unbilled rents receivable, net Increase in deferred charges and other assets, net Increase in deferred charges, goodwill and other assets (Increase) decrease in accounts receivable, net Decrease (increase) in accounts receivable, net Increase (decrease) in accounts payable, accrued expenses and other liabilities Increase in accounts payable, accrued expenses and other liabilities The net change during the reporting period in the amount at the balance sheet date including both: (a) rents and other amounts paid in advance by tenants and clients; and (b) security deposits paid in advance to protect the provider of a service, such as a lessor, against damage or nonpayment by the tenant (lessee) during the term of the agreement Increase Decrease In Rents Received In Advance And Security Deposits Decrease in rents received in advance and security deposits Decrease in accrued interest payable Decrease in accrued interest payable Net cash provided by operating activities Net cash provided by operating activities CASH FLOWS FROM INVESTING ACTIVITIES Payments to Acquire Businesses, Net of Cash Acquired Rental property acquisitions and related intangibles Additions to rental property and related intangibles Rental property additions and improvements Payments to Develop Real Estate Assets Development of rental property Net Sales Proceeds Proceeds from the sale of rental property Proceeds from the sale of property Payments to Acquire Loans Receivable Issuance of notes and mortgage receivable Proceeds from Collection of Loans Receivable Repayment of notes receivable Investment in unconsolidated joint ventures Investment in unconsolidated joint ventures This item represents the amount of distributions in excess of net earnings, which represents a return of investment, received from unconsolidated joint ventures and subsidiaries; these investments are accounted for under the equity method of accounting. Distributions In Excess Of Cumulative Earnings From Jvs Distributions in excess of cumulative earnings from unconsolidated joint ventures Business Acquisition, Contingent Consideration, Cash Paid Business Acquisition, Contingent Consideration, Cash Paid Payment of contingent consideration Earn out paid Increase Decrease In Restricted Cash Decrease in restricted cash Net cash used in investing activities Net cash provided by (used in) investing activities CASH FLOW FROM FINANCING ACTIVITIES Borrowings from revolving credit facility Repayment of revolving credit facility and money market loans Repayment of revolving credit facility Proceeds from the sale of senior unsecured notes Proceeds from senior unsecured notes Repayments of senior unsecured notes Repayment of senior unsecured notes Proceeds from Issuance of Secured Debt Proceeds from mortgages and loans payable Repayment of mortgages, loans payable and other obligations Repayment of mortgages, loans payable and other obligations Payment of financing costs Payment of financing costs Payment of dividends and distributions Payment of dividends and distributions Net cash provided used in financing activities Net cash provided by (used in) financing activities Net (decrease) increase in cash and cash equivalents Net increase in cash and cash equivalents Organization And Basis Of Presentation [Abstract] Organization Consolidation And Presentation Of Financial Statements Disclosure TextBlock Organization And Basis Of Presentation Significant Accounting Policies [Abstract] Significant Accounting Policies Textblock Significant Accounting Policies Real Estate Transactions [Abstract] Real Estate Disclosure [Text Block] Real Estate Transactions Investments In Unconsolidated Joint Ventures [Abstract] Equity Method Investments Disclosure TextBlock Investments In Unconsolidated Joint Ventures Deferred Charges, Goodwill And Other Assets [Abstract] Deferred Costs Capitalized Prepaid And Other Assets Disclosure TextBlock Deferred Charges, Goodwill And Other Assets Restricted Cash [Abstract] Restricted Assets Disclosure [Text Block] Restricted Cash Disposal Groups, Including Discontinued Operations, Disclosure [Text Block] Discontinued Operations Debt Disclosure [Abstract] Senior Unsecured Notes [Text Block] Senior Unsecured Notes [Text Block] Senior Unsecured Notes Schedule Of Line Of Credit Facilities TextBlock Unsecured Revolving Credit Facility Mortgages And Notes Payable [Text Block] Mortgages, Loans Payable And Other Obligations Employee Benefit 401(k) Plans And Deferred Retirement Compensation Agreements [Abstract] GeneralDiscussionOfPensionAndOtherPostretirementBenefitsAbstract Employee Benefit 401(k) Plans And Deferred Retirement Compensation Agreements Disclosure Of Fair Value Of Financial Instruments [Abstract] Fair Value Disclosures TextBlock Disclosure Of Fair Value Of Financial Instruments Commitments And Contingencies [Abstract] Commitments and Contingencies Disclosure Textblock Commitments And Contingencies Tenant Leases [Abstract] Leases Of Lessor Disclosure TextBlock Tenant Leases Mack-Cali Realty Corporation Stockholders' Equity [Abstract] Stockholders Equity Note Disclosure TextBlock Mack-Cali Realty Corporation Stockholders' Equity Noncontrolling Interests In Subsidiaries [Abstract] Minority Interest Disclosure TextBlock Noncontrolling Interests In Subsidiaries Segment Reporting [Abstract] Segment Reporting Disclosure Textblock Segment Reporting Property, Plant and Equipment, Policy [Text Block] Rental Property Real Estate Held for Development and Sale, Policy Rental Property Held For Sale And Discontinued Operations Equity Method Investments, Policy Investments In Unconsolidated Joint Ventures Cash and Cash Equivalents, Policy [Text Block] Cash And Cash Equivalents