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 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 Carrying Amount Investments in unconsolidated joint ventures Unbilled rents receivable, net Deferred charges, goodwill and other assets Total deferred charges, goodwill and other assets Deferred charges, goodwill and other assets, net Restricted Cash And Cash Equivalents Total restricted cash Restricted cash Accounts Receivable Net Accounts receivable, net of allowance for doubtful accounts of $1,513 and $2,584 Total assets Total assets LIABILITIES AND EQUITY Unsecured Debt Senior Unsecured Notes Senior unsecured notes Revolving credit facility Amount outstanding Outstanding borrowings under the facility Secured Debt Mortgages, loans payable and other obligations 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 89,127,942 and 89,076,578 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 Lease revenue Escalations and recoveries from tenants 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 The aggregate costs including administrative paperwork, real estate brokerage, title, and property management operations. Costs Of Real Estate Services Real estate services expenses General and administrative Depreciation and amortization Depreciation and amortization Costs and Expenses Total expenses Operating income Income from properties sold Operating income OTHER (EXPENSE) INCOME Interest expense Interest expense Interest and other investment income Interest and other investment income (loss) Equity in earnings (loss) of unconsolidated joint ventures Equity in (earnings) loss of unconsolidated joint venture, net Company's equity in earnings (loss) of unconsolidated joint ventures Realized gains on disposition of rental property Realized gains (losses) on sales, net Realized gains (losses) on disposition of rental property, net Nonoperating Income (Expense) Total other (expense) income Net income Net loss Net loss 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 Add (deduct): Noncontrolling interest in Operating Partnership Add (deduct): Noncontrolling interest in Operating Partnership Net income (loss) available to common shareholders Net loss available to common shareholders Net loss available to common shareholders Income (loss) from properties sold Basic earnings per common share: Net income available to common shareholders Net loss available to common shareholders Diluted earnings per common share: Earnings Per Share Diluted Net loss available to common unitholders 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 in consolidated joint ventures Redemption of common units for common stock, value Redemption of common units for common stock 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 Stock Issued During Period, Value, Restricted Stock Award, Gross Directors' deferred compensation plan, value 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 Amortization Of Deferred Stock Units Amortization Of Deferred Stock Units Amortization of deferred stock units Stock compensation Amortization of stock compensation Amortization of deferred financing costs Amortization of Other Deferred Charges Amortization of debt discount and mark-to-market Equity Method Investment Dividends Or Distributions Distributions of cumulative earnings from unconsolidated joint ventures Gain Loss On Disposition Of Assets Including Discontinued Operations Gain Loss On Disposition Of Assets Including Discontinued Operations Realized (gains) loss on disposition of rental property, net Changes in operating assets and liabilities: Increase Decrease In Unbilled Rent Receivables Increase Decrease In Unbilled Rent Receivables Decrease (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 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 Increase (decrease) in accrued interest payable Net cash provided by operating activities Net cash provided by operating activities CASH FLOWS FROM INVESTING ACTIVITIES Additions to rental property and related intangibles Rental property additions and improvements Purchase price of property Payments to Develop Real Estate Assets Development of rental property, other related costs and deposits Development of rental property Net Sales Proceeds Proceeds from the sale of rental property 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 Increase Decrease In Restricted Cash Increase in restricted cash Net cash used in investing activities Net cash 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 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 Business Acquisition, Contingent Consideration, Cash Paid Business Acquisition, Contingent Consideration, Cash Paid Payment of contingent consideration Earn out paid Payment of financing costs Payment of financing costs Proceeds from Noncontrolling Interests Cash from noncontrolling interests 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 decrease 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 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 Equity Method Investments, Policy Investments In Unconsolidated Joint Ventures Cash and Cash Equivalents, Policy [Text Block] Cash And Cash Equivalents Disclosure of entity's accounting policy for costs incurred in connection with obtaining finance. Deferred Financing Costs Policy Text Block Deferred Financing Costs Disclosure of the entity's accounting policy for costs incurred in connection with leases. Deferred Leasing Costs Policy Text Block Deferred Leasing Costs Goodwill and Intangible Assets, Goodwill, Policy [Policy Text Block] Goodwill Derivatives, Policy [Text Block] Derivative Instruments Revenue Recognition, Policy [Text Block] Revenue Recognition Allowance For Doubtful Accounts Policy [Policy Text Block] Allowance For Doubtful Accounts Policy [Policy Text Block] Allowance For Doubtful Accounts Income Tax, Policy [Text Block] Income And Other Taxes Earnings Per Share, Policy [Text Block] Earnings Per Share Disclosure of the entity's accounting policy for declaring and paying dividends and distributions. Dividends And Distributions Payable Policy Text Block Dividends And Distributions Payable Disclosure of the accounting policy for costs incurred in connection with stock issuances. Issuance Costs Policy Text Block Costs Incurred For Stock Issuances Share-based Compensation, Option and Incentive Plans Policy [Policy Text Block] Stock Compensation Other Comprehensive Income Policy [Text Block] Other Comprehensive Income Policy Text Block Other Comprehensive Income Fair Value Measurement, Policy [Policy Text Block] Fair Value Hierarchy Discontinued Operations, Policy [Policy Text Block] Discontinued Operations New Accounting Pronouncements, Policy [Policy Text Block] Impact Of Recently-Issued Accounting Standards Schedule of Estimated Useful Lives of Assets [Text Block] Schedule of Estimated Useful Lives of Assets [Text Block] Estimated Useful Lives Of Assets Schedule of Disposal Groups, Including Discontinued Operations, Income Statement, Balance Sheet and Additional Disclosures [Text Block] Summary Of Income From Properties Sold Schedule Of Unconsolidated Joint Ventures [Table Text Block] Schedule Of Unconsolidated Joint Ventures [Table Text Block] Summary Of Unconsolidated Joint Ventures