Quarterly report pursuant to Section 13 or 15(d)

Mack-Cali Realty Corporation Stockholders' Equity (Restricted Stock Awards And TSR-Based Awards) (Narrative) (Details)

v2.4.1.9
Mack-Cali Realty Corporation Stockholders' Equity (Restricted Stock Awards And TSR-Based Awards) (Narrative) (Details) (USD $)
In Millions, except Share data, unless otherwise specified
3 Months Ended 0 Months Ended 3 Months Ended 0 Months Ended 12 Months Ended 0 Months Ended
Mar. 31, 2015
item
Sep. 12, 2012
Mar. 31, 2014
Sep. 11, 2012
Dec. 31, 2013
May 11, 2015
Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Number of executive officers who departed 2cli_NumberOfExecutiveOfficersWhoDeparted            
Shares vested 37,392us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod            
Unvested restricted stock outstanding 313,337us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber           346,946us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber
Awards issued 3,786us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod            
Restricted Stock [Member]              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Unvested restricted stock outstanding 103,337us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber
/ us-gaap_AwardTypeAxis
= us-gaap_RestrictedStockMember
  414,483us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber
/ us-gaap_AwardTypeAxis
= us-gaap_RestrictedStockMember
       
Restricted stock awards unvested shares outstanding, performance contingent 210,000cli_RestrictedStockAwardsUnvestedSharesOutstandingPerformanceContingent
/ us-gaap_AwardTypeAxis
= us-gaap_RestrictedStockMember
           
Awards issued   319,667us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod
/ us-gaap_AwardTypeAxis
= us-gaap_RestrictedStockMember
         
Restricted Stock [Member] | Minimum [Member]              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Stock compensation vesting period 1 year            
Restricted Stock [Member] | Maximum [Member]              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Stock compensation vesting period 7 years            
Ratified Restricted Stock Awards [Member]              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Shares vested     109,667us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod
/ us-gaap_AwardTypeAxis
= cli_RatifiedRestrictedStockAwardsMember
       
Ratified Restricted Stock Awards [Member] | Minimum [Member]              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Stock compensation vesting period 5 years            
Ratified Restricted Stock Awards [Member] | Maximum [Member]              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Stock compensation vesting period 7 years            
Total Stockholder Return Based Awards [Member]              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Stock compensation vesting period 4 years            
Shares vested 357us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod
/ us-gaap_AwardTypeAxis
= cli_TotalStockholderReturnBasedAwardsMember
           
Shares granted and vested 528cli_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantedAndVestedInPeriod
/ us-gaap_AwardTypeAxis
= cli_TotalStockholderReturnBasedAwardsMember
           
Awards issued       5,160us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod
/ us-gaap_AwardTypeAxis
= cli_TotalStockholderReturnBasedAwardsMember
1,032us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod
/ us-gaap_AwardTypeAxis
= cli_TotalStockholderReturnBasedAwardsMember
   
Value of common stock received upon vesting of awards 1,000cli_ValueOfCommonStockReceivedUponVestingOfAwards
/ us-gaap_AwardTypeAxis
= cli_TotalStockholderReturnBasedAwardsMember
           
Shares issued 45,062us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensationGross
/ us-gaap_AwardTypeAxis
= cli_TotalStockholderReturnBasedAwardsMember
           
Total unrecognized compensation cost 1.2us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized
/ us-gaap_AwardTypeAxis
= cli_TotalStockholderReturnBasedAwardsMember
           
Total unrecognized compensation cost, period of recognition 1 year 3 months 18 days            
Scenario, Forecast [Member] | Ratified Restricted Stock Awards [Member]              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Shares vested           84,000us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod
/ us-gaap_AwardTypeAxis
= cli_RatifiedRestrictedStockAwardsMember
/ us-gaap_StatementScenarioAxis
= us-gaap_ScenarioForecastMember
 
Shares granted and vested           126,000cli_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantedAndVestedInPeriod
/ us-gaap_AwardTypeAxis
= cli_RatifiedRestrictedStockAwardsMember
/ us-gaap_StatementScenarioAxis
= us-gaap_ScenarioForecastMember
 
Scenario, Forecast [Member] | Total Stockholder Return Based Awards [Member]              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Shares vested           675us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod
/ us-gaap_AwardTypeAxis
= cli_TotalStockholderReturnBasedAwardsMember
/ us-gaap_StatementScenarioAxis
= us-gaap_ScenarioForecastMember
 
Shares issued           41,811us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensationGross
/ us-gaap_AwardTypeAxis
= cli_TotalStockholderReturnBasedAwardsMember
/ us-gaap_StatementScenarioAxis
= us-gaap_ScenarioForecastMember