CLI


Line plots across dimensions of each concept
Line plots across concepts
Tables

Table of contents



us-gaap:CommonStockValue
us-gaap:StatementEquityComponents
us-gaap:SharesOutstanding
us-gaap:SubsequentEventType
us-gaap:CommonStockSharesOutstanding

us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding

us-gaap:WeightedAverageNumberOfSharesOutstandingBasic

us-gaap:EarningsPerShareBasic
dei:LegalEntity

us-gaap:EarningsPerShareDiluted
dei:LegalEntity

us-gaap:IncomeLossFromContinuingOperationsPerBasicShare
dei:LegalEntity

us-gaap:IncomeLossFromContinuingOperationsPerDilutedShare
dei:LegalEntity

us-gaap:ComprehensiveIncomeNetOfTax
dei:LegalEntity

us-gaap:ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest
dei:LegalEntity

us-gaap:CostOfGoodsAndServicesSold
dei:LegalEntity
us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty

us-gaap:CostsAndExpenses
dei:LegalEntity
dei:LegalEntity
us-gaap:GainsLossesOnExtinguishmentOfDebt

us-gaap:GeneralAndAdministrativeExpense
dei:LegalEntity

us-gaap:IncomeLossFromContinuingOperations
dei:LegalEntity

us-gaap:IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest
dei:LegalEntity

us-gaap:InterestExpense
dei:LegalEntity
us-gaap:DerivativeInstrumentRisk, us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship, us-gaap:HedgingDesignation
us-gaap:CreditFacility, us-gaap:DebtInstrument
us-gaap:InterestExpenseDebt

us-gaap:NetIncomeLoss
dei:LegalEntity

us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic
dei:LegalEntity

us-gaap:NetIncomeLossAvailableToCommonStockholdersDiluted
dei:LegalEntity

us-gaap:OperatingCostsAndExpenses
dei:LegalEntity

us-gaap:OtherComprehensiveIncomeLossNetOfTax
dei:LegalEntity
dei:LegalEntity, us-gaap:PartnerTypeOfPartnersCapitalAccount
dei:LegalEntity, us-gaap:StatementEquityComponents
us-gaap:PartnerTypeOfPartnersCapitalAccount
us-gaap:StatementEquityComponents

us-gaap:ProfitLoss
dei:LegalEntity

us-gaap:Revenues
dei:LegalEntity
dei:LegalEntity, us-gaap:ProductOrService
us-gaap:ProductOrService
us-gaap:StatementBusinessSegments

us-gaap:Assets
dei:LegalEntity
us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:StatementBusinessSegments

us-gaap:Liabilities
dei:LegalEntity

us-gaap:LiabilitiesAndStockholdersEquity
dei:LegalEntity

us-gaap:StockholdersEquity
us-gaap:PartnerTypeOfPartnersCapitalAccount

us-gaap:CashAndCashEquivalentsAtCarryingValue
dei:LegalEntity

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents
dei:LegalEntity
us-gaap:DisposalGroupClassification
us-gaap:Land
us-gaap:DisposalGroupClassification, us-gaap:PropertyPlantAndEquipmentByType
us-gaap:PropertyPlantAndEquipmentByType

us-gaap:PropertyPlantAndEquipmentGross

us-gaap:InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures
dei:LegalEntity
us-gaap:ConsolidatedEntities
us-gaap:InvestmentsByConsolidatedAndNonconsolidatedEntities
us-gaap:MortgageLoansOnRealEstateDescriptionTypeOfProperty
us-gaap:MortgageLoansOnRealEstateDescriptionTypeOfProperty, us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName
us-gaap:StatementBusinessSegments

us-gaap:Goodwill
us-gaap:FiniteLivedIntangibleAssetsByMajorClass
us-gaap:FiniteLivedIntangibleAssetsNet

us-gaap:OtherAssets
dei:LegalEntity
us-gaap:DisposalGroupClassification

us-gaap:LongTermDebt
us-gaap:DebtInstrument
us-gaap:LongtermDebtType
us-gaap:CreditFacility
us-gaap:SecuredLongTermDebt
us-gaap:CreditFacility, us-gaap:SubsequentEventType

us-gaap:MinorityInterest
us-gaap:StatementEquityComponents

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFour

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFive

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive

us-gaap:OperatingLeaseLiability
us-gaap:AdjustmentsForNewAccountingPronouncements

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDue

us-gaap:LesseeOperatingLeaseLiabilityUndiscountedExcessAmount

us-gaap:StockholdersEquity
us-gaap:PartnerTypeOfPartnersCapitalAccount

us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest
us-gaap:StatementEquityComponents

us-gaap:CommonStockValue

us-gaap:AdditionalPaidInCapital

us-gaap:RetainedEarningsAccumulatedDeficit

us-gaap:MinorityInterest
us-gaap:StatementEquityComponents

us-gaap:MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders
dei:LegalEntity
dei:LegalEntity, us-gaap:PartnerTypeOfPartnersCapitalAccount
us-gaap:PartnerTypeOfPartnersCapitalAccount
us-gaap:StatementEquityComponents

us-gaap:NetCashProvidedByUsedInOperatingActivities
dei:LegalEntity

us-gaap:NetCashProvidedByUsedInInvestingActivities
dei:LegalEntity

us-gaap:NetCashProvidedByUsedInFinancingActivities
dei:LegalEntity

us-gaap:AmortizationOfFinancingCosts

us-gaap:DepreciationDepletionAndAmortization
dei:LegalEntity

us-gaap:NetCashProvidedByUsedInOperatingActivities
dei:LegalEntity

us-gaap:NetIncomeLoss
dei:LegalEntity

us-gaap:ProfitLoss
dei:LegalEntity

us-gaap:ShareBasedCompensation
dei:LegalEntity

us-gaap:NetCashProvidedByUsedInInvestingActivities
dei:LegalEntity

us-gaap:NetCashProvidedByUsedInFinancingActivities
dei:LegalEntity
us-gaap:DebtInstrument, us-gaap:DisposalGroupClassification, us-gaap:SubsequentEventType
us-gaap:RepaymentsOfLongTermDebt
us-gaap:DisposalGroupClassification, us-gaap:SubsequentEventType
us-gaap:StatementGeographical, us-gaap:DisposalGroupClassification, us-gaap:SubsequentEventType

us-gaap:PaymentsForRepurchaseOfCommonStock
dei:LegalEntity

us-gaap:DeferredTaxAssetsValuationAllowance
us-gaap:DisposalGroupClassification, us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations

cli:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationValue
dei:LegalEntity
dei:LegalEntity, us-gaap:PartnerTypeOfPartnersCapitalAccount
us-gaap:StatementEquityComponents

cli:AmortizationOfDebtDiscountAndMarkToMarket
dei:LegalEntity

cli:AmortizationOfDeferredStockUnits
dei:LegalEntity
us-gaap:TitleOfIndividual
cli:AnnualBaseSalary
us-gaap:TitleOfIndividual
cli:AnnualBaseSalaryForTargetPerformancePercentag
us-gaap:Range, us-gaap:TitleOfIndividual
cli:AnnualBonusOpportunityPercentage
us-gaap:TitleOfIndividual
us-gaap:Range
cli:AnnualBonusOpportunityThresholdPercentage
us-gaap:Range, us-gaap:TitleOfIndividual
us-gaap:TitleOfIndividual
us-gaap:Range, us-gaap:TitleOfIndividual
cli:AnnualHealthCoverage
us-gaap:TitleOfIndividual
cli:AnnualMaximumBonusPercentage
us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty, us-gaap:TaxPeriod
cli:AnnualPercentageOfCostForPhaseIn
us-gaap:ConsolidatedEntities, us-gaap:StatementScenario, us-gaap:RelatedPartyTransactionsByRelatedParty
cli:AnnualReturnFromCashFlowOperations
us-gaap:StatementScenario, us-gaap:RelatedPartyTransactionsByRelatedParty
cli:AnnualReturnOnEquityValue
us-gaap:ConsolidatedEntities, us-gaap:StatementScenario, us-gaap:RelatedPartyTransaction, us-gaap:RelatedPartyTransactionsByRelatedParty
cli:AnnualReturnOnEquityValueBaseReturn
us-gaap:ConsolidatedEntities, us-gaap:StatementScenario, us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:ConsolidatedEntities, us-gaap:StatementScenario, us-gaap:RelatedPartyTransaction, us-gaap:RelatedPartyTransactionsByRelatedParty
cli:AnnualReturnOnEquityValueCapitalBaseReturn
us-gaap:ConsolidatedEntities, us-gaap:StatementScenario, us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:StatementScenario, us-gaap:RelatedPartyTransaction, us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:Range, us-gaap:TitleOfIndividual
cli:AnnualTaxComplianceAssistance
us-gaap:MortgageLoansOnRealEstateDescriptionTypeOfProperty
cli:AreaOfMixedUseProperty

cli:BuildingsAndImprovementsNetOfAccumulatedDepreciation
us-gaap:DisposalGroupClassification
us-gaap:DisposalGroupClassification, us-gaap:PropertyPlantAndEquipmentByType

cli:CapitalizedDevelopmentConstructionSalariesAndOtherRelatedExpenses
us-gaap:TitleOfIndividual, us-gaap:AwardType
cli:CashDistributionPercent
us-gaap:SubsequentEventType
cli:CommonStockDividendsAndCommonUnitDistributionsPerShare

cli:CommonUnits

cli:ComprehensiveIncomeLossNetOfTaxAttributableToNoncontrollingInterestJointVenturePartnersNonredeemable
dei:LegalEntity

cli:ComprehensiveIncomeLossNetOfTaxAttributableToNoncontrollingInterestOperatingPartnershipsNonredeemable

cli:ComprehensiveIncomeLossNetOfTaxAttributableToRedeemableNoncontrollingInterest
dei:LegalEntity
us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty
cli:ConstructionCostsIncurred

cli:CostsOfRealEstateServices
dei:LegalEntity

cli:DeadDealAndTransactionRelatedCosts
dei:LegalEntity
us-gaap:CreditFacility, us-gaap:DebtInstrument
cli:DebtInstrumentClosingCostsToDefeaseLoan
us-gaap:DebtInstrument
cli:DebtInstrumentInitialTermCommitmentPercentageBorrowed
us-gaap:Range, us-gaap:CreditFacility
cli:DebtInstrumentMaximumCollateralPoolLeverageRatio
us-gaap:Range, us-gaap:CreditFacility, us-gaap:SubsequentEventType
us-gaap:DebtInstrument
cli:DebtInstrumentTermCommitmentFeePerAnnum
us-gaap:Range, us-gaap:CreditFacility
cli:DebtInstrumentTotalLeverageRatio
us-gaap:Range, us-gaap:CreditFacility, us-gaap:SubsequentEventType

cli:DepreciationAmortizationOnDiscontinuedOperations

cli:DisposalGroupIncludingDiscontinuedOperationGainLossOnDispositionOfAssets
us-gaap:DisposalGroupClassification
cli:DisposalGroupIncludingDiscontinuedOperationLandNetValue
us-gaap:DisposalGroupClassification, us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations
us-gaap:DisposalGroupClassification
cli:DisposalGroupIncludingDiscontinuedOperationPropertyPlantAndEquipmentNetValue
us-gaap:DisposalGroupClassification, us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations

cli:DistributionsInExcessOfCumulativeEarningsFromJvs
dei:LegalEntity
us-gaap:ConsolidatedEntities, us-gaap:RelatedPartyTransactionsByRelatedParty
cli:EquityCapitalizationExcessPercent

cli:EquityMethodInvestmentAmortizationOfBasisDifference
us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty
cli:EstimatedCostOfProject
us-gaap:DisposalGroupClassification
cli:GainLossOnDispositionOfLandDiscontinuedOperations
us-gaap:DisposalGroupClassification, us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations

cli:GainLossOnDispositionOfRealEstateDiscontinuedOperationsNetOfUnrealizedGainLosses
us-gaap:DisposalGroupClassification

cli:GainLossOnSaleOfRealizedAndUnrealizedPropertyPlantEquipment
dei:LegalEntity

cli:ImpairmentOfLandAndOther
dei:LegalEntity
us-gaap:MortgageLoansOnRealEstateDescriptionTypeOfProperty
us-gaap:MortgageLoansOnRealEstateDescriptionTypeOfProperty, us-gaap:DisposalGroupClassification
us-gaap:StatementGeographical
us-gaap:StatementGeographical, us-gaap:DisposalGroupClassification

cli:ImpairmentOfLandAndOtherIncludingContinuedAndDiscontinuedOperations
dei:LegalEntity
us-gaap:TitleOfIndividual, us-gaap:AwardType
cli:IncomeAllocationEquivalentPercent
us-gaap:MortgageLoansOnRealEstateDescriptionTypeOfProperty, us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName
cli:IncomeFromSaleOfEconomicTaxCreditCertificate

cli:IncomeLossFromContinuingOperationsBasic
dei:LegalEntity

cli:IncomeLossFromContinuingOperationsDiluted

cli:IncomeLossFromContinuingOperationsDilutedEarningsPerShare
dei:LegalEntity

cli:IncomeLossFromDiscontinuedOperationsAvailableToCommonShareholders
dei:LegalEntity

cli:IncreaseDecreaseImpairmentOfLandAndOt

cli:IncreaseDecreaseInRentsReceivedInAdvanceAndSecurityDeposits
dei:LegalEntity

cli:IncreaseDecreaseInUnbilledRentReceivables
dei:LegalEntity
us-gaap:ConsolidatedEntities, us-gaap:StatementScenario, us-gaap:RelatedPartyTransactionsByRelatedParty
cli:InternalRateOfReturnPercent

cli:InvestmentIncomeLossNonoperating
dei:LegalEntity

cli:LeasingPersonnelCosts

cli:ManagementLeasingDevelopmentAndOtherServicesFees
us-gaap:TitleOfIndividual, us-gaap:AwardType
cli:MaximumPerformanceSalesVolume
us-gaap:StatementEquityComponents
cli:MinorityInterestDecreaseFromNoncontrollingInterest
dei:LegalEntity, us-gaap:PartnerTypeOfPartnersCapitalAccount
cli:MinorityInterestIncreaseDecreaseFromRedemptions
us-gaap:PartnerTypeOfPartnersCapitalAccount
us-gaap:StatementEquityComponents
us-gaap:ShareRepurchaseProgram
cli:MonthlyCashInvestmentWithoutRestrictionMaximum
us-gaap:RelatedPartyTransactionsByRelatedParty
cli:MonthlySalaryAndWageOfficer
us-gaap:ConsolidatedEntities
cli:NoncontrollingInterestEstimatedRedemptionValue

cli:NoncontrollingInterestInDiscontinuedOperations
us-gaap:PartnerTypeOfPartnersCapitalAccount
cli:NoncontrollingInterestIncreaseDecreaseFromSubsidiaryEquityIssuance
us-gaap:StatementEquityComponents

cli:NoncontrollingInterestIncreaseFromDistributionsToNoncontrollingInterestHolders
dei:LegalEntity
dei:LegalEntity, us-gaap:PartnerTypeOfPartnersCapitalAccount
us-gaap:StatementEquityComponents

cli:NoncontrollingInterestRedemptionValueAdjustmentRedeemable
dei:LegalEntity
us-gaap:PartnerTypeOfPartnersCapitalAccount
us-gaap:StatementEquityComponents

cli:NoncontrollingInterestRedemptionValueAdjustmentRedeemableBeforeOperatingPartnership
dei:LegalEntity

cli:NoncontrollingInterestRedemptionValueAdjustmentRedeemableInOperatingPartnership

cli:NonoperatingIncomeExpenseIncludingEquityMethodInvestments
dei:LegalEntity

cli:NumberOfPayments

cli:OperatingAndInterestExpenses
us-gaap:StatementBusinessSegments

cli:OperatingLeaseExpenseIncludingSubleaseRentals
us-gaap:DisposalGroupClassification, us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations
cli:PartnersCapitalAccountValueUnitsRedeemed
us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations
cli:PaymentOfClosingCosts
us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty
cli:PaymentsInLieuOfPropertyTaxAsPercentageBasedOnLandValue
us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty
cli:PaymentsInLieuOfPropertyTaxAsPercentageOfGrossRevenues
us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty, us-gaap:TaxPeriod
us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty
cli:PaymentsInLieuOfPropertyTaxAsPercentageOfTotalProjectCost
us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty, us-gaap:TaxPeriod
us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty
cli:PaymentsInLieuOfPropertyTaxes

cli:PaymentsToDevelopPropertyAndOtherRelatedCosts
dei:LegalEntity
us-gaap:CreditFacility, us-gaap:DebtInstrument
cli:PercentOfLineOfCreditOutstanding
us-gaap:CreditFacility, us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName, us-gaap:LongtermDebtType
us-gaap:TitleOfIndividual, us-gaap:PlanName
cli:PercentageOfAward
us-gaap:Range, us-gaap:AwardType, us-gaap:PlanName, us-gaap:Vesting
cli:PercentageOfSharesVested
us-gaap:TitleOfIndividual
cli:PerformanceBasedVestingConditionsPercentage
us-gaap:ConsolidatedEntities, us-gaap:Range, us-gaap:RelatedPartyTransaction
cli:PreferredUnitsContributionToObtainEquityUnits
us-gaap:ConsolidatedEntities, us-gaap:PreferredUnitsByName
cli:ProRataDistributionPercent
us-gaap:ConsolidatedEntities, us-gaap:StatementScenario, us-gaap:PreferredUnitsByName
us-gaap:ConsolidatedEntities, us-gaap:StatementScenario, us-gaap:StatementEquityComponents
us-gaap:ConsolidatedEntities, us-gaap:StatementScenario, us-gaap:RelatedPartyTransactionsByRelatedParty
cli:ProRataDistributionPercentCashFlowFromCapitalEvents
us-gaap:MortgageLoansOnRealEstateDescriptionTypeOfProperty, us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName
cli:ProceedsFromEconomicTaxCreditAnnual
us-gaap:MortgageLoansOnRealEstateDescriptionTypeOfProperty, us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName
cli:ProceedsFromEconomicTaxCreditTotal
us-gaap:StatementGeographical, us-gaap:DisposalGroupClassification, us-gaap:SubsequentEventType
cli:ProceedsFromSaleOfBuildingsNet

cli:PropertyImpairments
dei:LegalEntity

cli:PropertyNetBookValue
us-gaap:PropertyPlantAndEquipmentByType

cli:RealEstateDevelopmentCostsIncurred
us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty
us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty, us-gaap:LongtermDebtType
us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty, us-gaap:PropertyPlantAndEquipmentByType
us-gaap:MortgageLoansOnRealEstateDescriptionTypeOfProperty
cli:RealEstatePropertyOwnedAndInvestmentInterestArea

cli:RealizedGainsLossOnDispositionOfAssetsNet
dei:LegalEntity

cli:RebalanceOfOwnershipPercentage
us-gaap:ConsolidatedEntities, us-gaap:StatementEquityComponents
cli:RedeemableNoncontrollingInterestDecreaseFromDistribution
us-gaap:PreferredUnitsByName, us-gaap:StatementEquityComponents
us-gaap:StatementEquityComponents

cli:RedeemableNoncontrollingInterestRedemptionValueAdjustment
dei:LegalEntity
dei:LegalEntity, us-gaap:PartnerTypeOfPartnersCapitalAccount
us-gaap:ConsolidatedEntities, us-gaap:StatementEquityComponents
us-gaap:StatementEquityComponents

cli:RedemptionOfCommonUnits
dei:LegalEntity
dei:LegalEntity, us-gaap:PartnerTypeOfPartnersCapitalAccount
us-gaap:StatementEquityComponents
dei:LegalEntity, us-gaap:PartnerTypeOfPartnersCapitalAccount
cli:RedemptionOfCommonUnitsShares
us-gaap:Range, us-gaap:TitleOfIndividual
cli:ReimbursementForRelocationCosts
us-gaap:Range, us-gaap:TitleOfIndividual
cli:ReimbursementOfAttorneysFeesToNegotiateEmploymentAgreement

cli:ReimbursementOfExpenses
dei:LegalEntity
us-gaap:RestructuringCostAndReserve
cli:RestructuringCostsGeneralAndAdministrationExpense
us-gaap:RestructuringCostAndReserve
cli:RestructuringCostsOperatingServices
us-gaap:ConsolidatedEntities, us-gaap:RelatedPartyTransaction
cli:RightOfFirstRefusalToInvestInPreferredUnitsAmount

cli:SegmentReportingInformationNetOperatingIncomeLossForReportableSegment
dei:LegalEntity
us-gaap:StatementBusinessSegments
us-gaap:TitleOfIndividual
cli:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAnnualAggregateGrantDateFairValue
us-gaap:TitleOfIndividual, us-gaap:AwardType
cli:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsPercentOfEstimatedNetAssetValue
us-gaap:TitleOfIndividual, us-gaap:PlanName
us-gaap:TitleOfIndividual, us-gaap:AwardType
cli:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsTargetGrantValue
us-gaap:Range, us-gaap:TitleOfIndividual, us-gaap:AwardType
cli:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsThresholdEarningPercentage
us-gaap:TitleOfIndividual, us-gaap:AwardType, us-gaap:Vesting
cli:ShareBasedCompensationArrangementByShareBasedPaymentAwardThresholdSharePriceTrigger
us-gaap:Range, us-gaap:AwardType
cli:StayOnAwardAgreementCosts
us-gaap:PartnerTypeOfPartnersCapitalAccount
cli:StockBasedCompensationAttributableToNoncontrollingInterest
us-gaap:StatementEquityComponents
dei:LegalEntity, us-gaap:PartnerTypeOfPartnersCapitalAccount
cli:StockIssuedDuringPeriodSharesLongTermIncentivePlanVested
us-gaap:StatementEquityComponents
cli:StockIssuedDuringPeriodValueLongTermIncentivePlanUnitsForfeited
us-gaap:TitleOfIndividual, us-gaap:AwardType
cli:TargetPerformanceSalesVolume
us-gaap:TitleOfIndividual, us-gaap:AwardType
cli:ThresholdPerformanceSalesValue
us-gaap:TitleOfIndividual
cli:TimeBasedVestingCondtionsPercentage
us-gaap:AwardType, us-gaap:PlanName
cli:TotalStockholderReturnPercent
us-gaap:AwardType, us-gaap:PlanName, us-gaap:SubsequentEventType
us-gaap:PlanName

cli:UnrealizedGainLossOnDispositionOfRentalProperty
us-gaap:DisposalGroupClassification, us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations
us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations
us-gaap:PartnerTypeOfPartnersCapitalAccount
us-gaap:AdjustmentsToAdditionalPaidInCapitalDividendsInExcessOfRetainedEarnings

us-gaap:AmortizationOfFinancingCostsAndDiscounts
dei:LegalEntity

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect
dei:LegalEntity

us-gaap:CashProvidedByUsedInInvestingActivitiesDiscontinuedOperations
dei:LegalEntity

us-gaap:CashProvidedByUsedInOperatingActivitiesDiscontinuedOperations
dei:LegalEntity
us-gaap:Range, us-gaap:PlanName
us-gaap:DeferredCompensationArrangementWithIndividualExercisePrice

us-gaap:DepreciationAndAmortization
dei:LegalEntity
us-gaap:DerivativeInstrumentRisk, us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship, us-gaap:HedgingDesignation, us-gaap:IncomeStatementLocation
us-gaap:DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet

us-gaap:DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax
dei:LegalEntity

us-gaap:DiscontinuedOperationIncomeLossFromDiscontinuedOperationDuringPhaseOutPeriodNetOfTax
dei:LegalEntity

us-gaap:DisposalGroupIncludingDiscontinuedOperationDepreciationAndAmortization
dei:LegalEntity

us-gaap:DisposalGroupIncludingDiscontinuedOperationInterestExpense

us-gaap:DisposalGroupIncludingDiscontinuedOperationOperatingExpense

us-gaap:DisposalGroupIncludingDiscontinuedOperationRevenue

us-gaap:DividendsCommonStock
us-gaap:StatementEquityComponents
us-gaap:SubsequentEventType
us-gaap:DividendsCommonStockCash

us-gaap:EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate

us-gaap:EmployeeBenefitsAndShareBasedCompensation

us-gaap:EquityMethodInvestmentDividendsOrDistributions
dei:LegalEntity
us-gaap:LongtermDebtType
us-gaap:ExtinguishmentOfDebtAmount

us-gaap:GainLossOnDispositionOfAssets
dei:LegalEntity
us-gaap:MortgageLoansOnRealEstateDescriptionTypeOfProperty, us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName
us-gaap:GainOnSaleOfInvestments
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName, us-gaap:SubsequentEventType

us-gaap:ImpairmentOfRealEstate
dei:LegalEntity

us-gaap:IncomeLossFromDiscontinuedOperationsNetOfTax
dei:LegalEntity

us-gaap:IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare
dei:LegalEntity

us-gaap:IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare
dei:LegalEntity

us-gaap:IncomeLossFromEquityMethodInvestments
dei:LegalEntity
us-gaap:MortgageLoansOnRealEstateDescriptionTypeOfProperty
us-gaap:MortgageLoansOnRealEstateDescriptionTypeOfProperty, us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName
us-gaap:StatementBusinessSegments

us-gaap:IncreaseDecreaseInAccountsPayableAndAccruedLiabilities
dei:LegalEntity

us-gaap:IncreaseDecreaseInInterestPayableNet
dei:LegalEntity

us-gaap:IncreaseDecreaseInLeasingReceivables
dei:LegalEntity

us-gaap:IncreaseDecreaseInOtherOperatingAssets
dei:LegalEntity

us-gaap:InterestCostsCapitalized
us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:InterestPaid
us-gaap:DisposalGroupClassification
us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:LegalFees

us-gaap:MinorityInterestPeriodIncreaseDecrease
dei:LegalEntity
dei:LegalEntity, us-gaap:PartnerTypeOfPartnersCapitalAccount
us-gaap:StatementEquityComponents

us-gaap:NetCashProvidedByUsedInInvestingActivitiesContinuingOperations
dei:LegalEntity

us-gaap:NetCashProvidedByUsedInOperatingActivitiesContinuingOperations
dei:LegalEntity
us-gaap:PartnerTypeOfPartnersCapitalAccount
us-gaap:NetIncomeLossAttributableToNonredeemableNoncontrollingInterest
us-gaap:StatementEquityComponents

us-gaap:NetIncomeLossAttributableToRedeemableNoncontrollingInterest
dei:LegalEntity
us-gaap:ConsolidatedEntities, us-gaap:StatementEquityComponents
us-gaap:PreferredUnitsByName, us-gaap:StatementEquityComponents
us-gaap:StatementEquityComponents

us-gaap:NetIncomeLossIncludingPortionAttributableToNonredeemableNoncontrollingInterest
dei:LegalEntity
dei:LegalEntity, us-gaap:PartnerTypeOfPartnersCapitalAccount
us-gaap:StatementEquityComponents

us-gaap:NoncontrollingInterestInNetIncomeLossJointVenturePartnersNonredeemable
dei:LegalEntity

us-gaap:NoncontrollingInterestInNetIncomeLossOperatingPartnershipsNonredeemable

us-gaap:OperatingLeasesIncomeStatementLeaseRevenue
dei:LegalEntity

us-gaap:OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax
dei:LegalEntity
dei:LegalEntity
us-gaap:PaymentsForFees
dei:LegalEntity, us-gaap:StatementScenario
dei:LegalEntity, us-gaap:SubsequentEventType

us-gaap:PaymentsForRepurchaseOfEquity

us-gaap:PaymentsOfCapitalDistribution
dei:LegalEntity

us-gaap:PaymentsOfFinancingCosts
dei:LegalEntity

us-gaap:PaymentsToAcquireAndDevelopRealEstate
dei:LegalEntity

us-gaap:PaymentsToAcquireBusinessesNetOfCashAcquired
dei:LegalEntity

us-gaap:PaymentsToAcquireInterestInJointVenture
dei:LegalEntity

us-gaap:ProceedsFromCollectionOfLoansReceivable
dei:LegalEntity

us-gaap:ProceedsFromIssuanceOfSecuredDebt
dei:LegalEntity
us-gaap:CreditFacility
us-gaap:ProceedsFromLinesOfCredit

us-gaap:ProceedsFromPaymentsToMinorityShareholders
dei:LegalEntity

us-gaap:ProceedsFromSaleOfBuildings
dei:LegalEntity
us-gaap:StatementGeographical, us-gaap:DisposalGroupClassification
us-gaap:StatementGeographical, us-gaap:DisposalGroupClassification, us-gaap:SubsequentEventType
us-gaap:DisposalGroupClassification
us-gaap:ProceedsFromSaleOfLandHeldforinvestment
us-gaap:DisposalGroupClassification, us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations
us-gaap:MortgageLoansOnRealEstateDescriptionTypeOfProperty, us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName
us-gaap:ProceedsFromSaleOfPropertyPlantAndEquipment
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName
us-gaap:MortgageLoansOnRealEstateDescriptionTypeOfProperty, us-gaap:DisposalGroupClassification
us-gaap:ProceedsFromSaleOfRealEstate

us-gaap:ProceedsFromUnsecuredLinesOfCredit
dei:LegalEntity

us-gaap:RealEstateTaxExpense
dei:LegalEntity
us-gaap:CreditFacility
us-gaap:RepaymentsOfDebt

us-gaap:RepaymentsOfLinesOfCredit
dei:LegalEntity

us-gaap:RepaymentsOfSecuredDebt
dei:LegalEntity
us-gaap:LongtermDebtType, us-gaap:SubsequentEventType
us-gaap:RepaymentsOfUnsecuredDebt

us-gaap:RestrictedStockExpense
us-gaap:IncomeStatementLocation, us-gaap:RestructuringCostAndReserve
us-gaap:RestructuringCosts
us-gaap:RestructuringCostAndReserve
us-gaap:Range, us-gaap:AwardType
us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardAcceleratedCompensationCost

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue
us-gaap:RelatedPartyTransactionsByRelatedParty, us-gaap:SubsequentEventType
us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross
us-gaap:TitleOfIndividual

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue

us-gaap:ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice
dei:LegalEntity, us-gaap:PartnerTypeOfPartnersCapitalAccount
us-gaap:StockDividendsShares
us-gaap:StatementEquityComponents
dei:LegalEntity, us-gaap:PartnerTypeOfPartnersCapitalAccount
us-gaap:StockIssuedDuringPeriodSharesConversionOfUnits
us-gaap:StatementEquityComponents
dei:LegalEntity, us-gaap:PartnerTypeOfPartnersCapitalAccount
us-gaap:StockIssuedDuringPeriodSharesRestrictedStockAwardGross
us-gaap:StatementEquityComponents
dei:LegalEntity, us-gaap:PartnerTypeOfPartnersCapitalAccount
us-gaap:StockIssuedDuringPeriodSharesShareBasedCompensation
us-gaap:StatementEquityComponents

us-gaap:StockIssuedDuringPeriodValueDividendReinvestmentPlan
dei:LegalEntity
dei:LegalEntity, us-gaap:PartnerTypeOfPartnersCapitalAccount
us-gaap:StatementEquityComponents

us-gaap:StockIssuedDuringPeriodValueRestrictedStockAwardGross
dei:LegalEntity
dei:LegalEntity, us-gaap:PartnerTypeOfPartnersCapitalAccount
us-gaap:PartnerTypeOfPartnersCapitalAccount
us-gaap:StatementEquityComponents

us-gaap:StockIssuedDuringPeriodValueShareBasedCompensationForfeited
dei:LegalEntity
dei:LegalEntity, us-gaap:PartnerTypeOfPartnersCapitalAccount
us-gaap:StatementEquityComponents

us-gaap:StockOptionPlanExpense
us-gaap:AwardType

us-gaap:StockRepurchasedAndRetiredDuringPeriodValue
dei:LegalEntity
dei:LegalEntity, us-gaap:PartnerTypeOfPartnersCapitalAccount
us-gaap:PartnerTypeOfPartnersCapitalAccount
us-gaap:StatementEquityComponents
us-gaap:ConsolidatedEntities, us-gaap:StatementEquityComponents
us-gaap:TemporaryEquityStockIssuedDuringPeriodValueNewIssues
us-gaap:PreferredUnitsByName, us-gaap:StatementEquityComponents
us-gaap:StatementEquityComponents

us-gaap:UnrealizedGainLossOnInvestments
us-gaap:DisposalGroupClassification
us-gaap:StatementGeographical
us-gaap:StatementGeographical, us-gaap:DisposalGroupClassification
dei:LegalEntity
us-gaap:WeightedAverageLimitedPartnershipUnitsOutstanding
dei:LegalEntity
us-gaap:WeightedAverageLimitedPartnershipUnitsOutstandingDiluted

cli:AccumulatedAmortizationLeasingAndFinancingCosts
us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty
cli:AmountOfProjectCostsFunded
us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty
cli:AmountToFund
us-gaap:DisposalGroupClassification
cli:AreaOfRealEstatePropertyHeldForSale
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName, us-gaap:DisposalGroupClassification, us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations
us-gaap:DisposalGroupClassification
cli:AssetsHeldForSaleNotPartOfDisposalGroupAccountsPayableAccruedExpensesAndOtherLiabilities
us-gaap:DisposalGroupClassification, us-gaap:LongLivedAssetsHeldForSaleByAssetType
us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty, us-gaap:DisposalGroupClassification
us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty, us-gaap:StatementGeographical, us-gaap:DisposalGroupClassification
us-gaap:StatementGeographical, us-gaap:DisposalGroupClassification
us-gaap:StatementGeographical, us-gaap:DisposalGroupClassification, us-gaap:LongLivedAssetsHeldForSaleByAssetType
us-gaap:DisposalGroupClassification
cli:AssetsHeldForSaleNotPartOfDisposalGroupAccountsPayableTotalBelowMarketLiability
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us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty, us-gaap:StatementGeographical, us-gaap:DisposalGroupClassification
us-gaap:StatementGeographical, us-gaap:DisposalGroupClassification
us-gaap:DisposalGroupClassification
cli:AssetsHeldForSaleNotPartOfDisposalGroupAccountsPayableUnearnedRentsDeferredRentalIncome
us-gaap:DisposalGroupClassification, us-gaap:LongLivedAssetsHeldForSaleByAssetType
us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty, us-gaap:DisposalGroupClassification
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us-gaap:StatementGeographical, us-gaap:DisposalGroupClassification
us-gaap:StatementGeographical, us-gaap:DisposalGroupClassification, us-gaap:LongLivedAssetsHeldForSaleByAssetType
us-gaap:DisposalGroupClassification
cli:AssetsHeldForSaleNotPartOfDisposalGroupDeferredChargesAndOtherAssets
us-gaap:DisposalGroupClassification, us-gaap:LongLivedAssetsHeldForSaleByAssetType
us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty, us-gaap:DisposalGroupClassification
us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty, us-gaap:StatementGeographical, us-gaap:DisposalGroupClassification
us-gaap:StatementGeographical, us-gaap:DisposalGroupClassification
us-gaap:StatementGeographical, us-gaap:DisposalGroupClassification, us-gaap:LongLivedAssetsHeldForSaleByAssetType
us-gaap:DisposalGroupClassification
cli:AssetsHeldForSaleNotPartOfDisposalGroupDeferredChargesNet
us-gaap:DisposalGroupClassification, us-gaap:LongLivedAssetsHeldForSaleByAssetType
us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty, us-gaap:DisposalGroupClassification
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us-gaap:StatementGeographical, us-gaap:DisposalGroupClassification
us-gaap:StatementGeographical, us-gaap:DisposalGroupClassification, us-gaap:LongLivedAssetsHeldForSaleByAssetType
us-gaap:DisposalGroupClassification
cli:AssetsHeldForSaleNotPartOfDisposalGroupDeferredRentReceivablesNet
us-gaap:DisposalGroupClassification, us-gaap:LongLivedAssetsHeldForSaleByAssetType
us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty, us-gaap:DisposalGroupClassification
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us-gaap:StatementGeographical, us-gaap:DisposalGroupClassification
us-gaap:StatementGeographical, us-gaap:DisposalGroupClassification, us-gaap:LongLivedAssetsHeldForSaleByAssetType
us-gaap:DisposalGroupClassification
cli:AssetsHeldForSaleNotPartOfDisposalGroupMortgagesLoansPayableNet
us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty, us-gaap:DisposalGroupClassification
us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty, us-gaap:StatementGeographical, us-gaap:DisposalGroupClassification
us-gaap:StatementGeographical, us-gaap:DisposalGroupClassification
us-gaap:DisposalGroupClassification
cli:AssetsHeldForSaleNotPartOfDisposalGroupTotalIntangiblesNet
us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty, us-gaap:DisposalGroupClassification
us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty, us-gaap:StatementGeographical, us-gaap:DisposalGroupClassification
us-gaap:StatementGeographical, us-gaap:DisposalGroupClassification

cli:AssetsRightOfUse

cli:AssetsRightOfUseLiability
us-gaap:DisposalGroupClassification
cli:BuildingsAndImprovementsAvailableForSale
us-gaap:DisposalGroupClassification, us-gaap:LongLivedAssetsHeldForSaleByAssetType
us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty, us-gaap:DisposalGroupClassification
us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty, us-gaap:StatementGeographical, us-gaap:DisposalGroupClassification
us-gaap:StatementGeographical, us-gaap:DisposalGroupClassification
us-gaap:StatementGeographical, us-gaap:DisposalGroupClassification, us-gaap:LongLivedAssetsHeldForSaleByAssetType

cli:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAboveMarketLeases

cli:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedBelowMarketLeases

cli:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedInPlaceLeases
us-gaap:SubsequentEventType
cli:CommonUnitsOutstanding

cli:ConsolidatedJointVenturesMortgages

cli:ConsolidatedJointVenturesOtherAssets

cli:ConsolidatedJointVenturesOtherLiabilities

cli:ConsolidatedJointVenturesRealEstateAssets

cli:DebtDiscountPremiumFutureAmortizationGross

cli:DebtDiscountPremiumFutureAmortizationNet

cli:DebtDiscountPremiumFutureAmortizationYearFive

cli:DebtDiscountPremiumFutureAmortizationYearFour

cli:DebtDiscountPremiumFutureAmortizationYearOne

cli:DebtDiscountPremiumFutureAmortizationYearSix

cli:DebtDiscountPremiumFutureAmortizationYearThree

cli:DebtDiscountPremiumFutureAmortizationYearTwo
us-gaap:Range, us-gaap:CreditFacility
cli:DebtInstrumentCovenantComplianceFixedChargeCoverage
us-gaap:Range, us-gaap:DebtInstrument
us-gaap:Range, us-gaap:DebtInstrument
cli:DebtInstrumentCovenantComplianceLeverageRatio
us-gaap:Range, us-gaap:CreditFacility
cli:DebtInstrumentCovenantComplianceUnencumberedPropertyInterestCoverage
us-gaap:Range, us-gaap:DebtInstrument

cli:DebtInstrumentUnamortizedDiscountCosts

cli:DebtInstrumentUnamortizedPremiumAndPrincipalCosts
us-gaap:CreditFacility
cli:DebtLoansPayableAndOtherObligationsNet

cli:DeferredCostsGross

cli:DevelopmentAndConstructionInProgressIncludingLand
us-gaap:RelatedPartyTransactionsByRelatedParty
cli:EquityMethodInvestmentSummarizedFinancialInformationOtherAssets
us-gaap:RelatedPartyTransactionsByRelatedParty
cli:EquityMethodInvestmentSummarizedFinancialInformationOtherLiabilities
us-gaap:RelatedPartyTransactionsByRelatedParty
cli:EquityMethodInvestmentSummarizedFinancialInformationSecuredDebt

cli:GeneralPartnerOwnershipPercentage
us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty, us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName
cli:IndirectOwnershipPercentage

cli:LandAndLeasehold
dei:LegalEntity
us-gaap:Range, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:MeasurementInputType
cli:LandHeldForSaleFairValue
us-gaap:CreditFacility, us-gaap:DebtInstrument
cli:LineOfCreditFacilityBasisPointFacilityFee

cli:LongLivedAssets
us-gaap:StatementBusinessSegments

cli:LongTermDebtAdjustedTotalDebtBeforeDebtDiscountAndDeferredFinancingCosts

cli:LongTermDebtAmortizationAndRepaymentsOfPrincipalAfterYearFive

cli:LongTermDebtAmortizationAndRepaymentsOfPrincipalGross

cli:LongTermDebtAmortizationAndRepaymentsOfPrincipalYearFive

cli:LongTermDebtAmortizationAndRepaymentsOfPrincipalYearFour

cli:LongTermDebtAmortizationAndRepaymentsOfPrincipalYearOne

cli:LongTermDebtAmortizationAndRepaymentsOfPrincipalYearSix

cli:LongTermDebtAmortizationAndRepaymentsOfPrincipalYearThree

cli:LongTermDebtAmortizationAndRepaymentsOfPrincipalYearTwo

cli:LongTermDebtMaturitiesRepaymentsOfPrincipal

cli:LongTermDebtMaturitiesRepaymentsOfPrincipalGross

cli:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearSix
us-gaap:SubsequentEventType
cli:LongTermIncentivePlanUnitsOutstanding
us-gaap:ConsolidatedEntities, us-gaap:MortgageLoansOnRealEstateDescriptionTypeOfProperty, us-gaap:LossContingenciesByNatureOfContingency
cli:LongTermLineOfCreditGuaranteedAmount
us-gaap:CreditFacility, us-gaap:DebtInstrument
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName

cli:MortgagePropertyCarryingValue
us-gaap:MortgageLoansOnRealEstateDescriptionTypeOfProperty

cli:NetInvestmentInRentalPropertyAndRentalPropertyHeldForSale
dei:LegalEntity
us-gaap:MortgageLoansOnRealEstateDescriptionTypeOfProperty
cli:NumberOfTenants
us-gaap:DisposalGroupClassification, us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations
cli:NumberOfUnitsSold
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName
cli:PercentageOfInterestInDevelopableLand

cli:PercentageOfUnitsForfeited
us-gaap:SubsequentEventType

cli:RealEstateAggregateCostTaxPurpose

cli:RealEstateHeldForSaleAccumulatedDepreciation

cli:RentalPropertyHeldForSaleNet
dei:LegalEntity
us-gaap:DisposalGroupClassification
us-gaap:DisposalGroupClassification, us-gaap:LongLivedAssetsHeldForSaleByAssetType
us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty, us-gaap:DisposalGroupClassification
us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty, us-gaap:StatementGeographical, us-gaap:DisposalGroupClassification
us-gaap:StatementGeographical, us-gaap:DisposalGroupClassification
us-gaap:StatementGeographical, us-gaap:DisposalGroupClassification, us-gaap:LongLivedAssetsHeldForSaleByAssetType

cli:RentsReceivedInAdvanceAndSecurityDeposits
dei:LegalEntity
us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty, us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName
cli:ResidualOwnershipInterest
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName
us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty, us-gaap:StatementGeographical, us-gaap:DisposalGroupClassification
cli:ReversalOfValuationAllowance
us-gaap:StatementGeographical, us-gaap:DisposalGroupClassification, us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations
us-gaap:CreditFacility
cli:UnamortizedDeferredFinancingCosts
us-gaap:LongtermDebtType
us-gaap:CreditFacility
cli:UnencumberedPropertyAppraisalValue
us-gaap:CreditFacility, us-gaap:SubsequentEventType
us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty, us-gaap:CreditFacility
us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty, us-gaap:CreditFacility, us-gaap:SubsequentEventType
us-gaap:DisposalGroupClassification
cli:UnrealizedGainLossOnInvestmentsHeldForSale
us-gaap:DisposalGroupClassification, us-gaap:LongLivedAssetsHeldForSaleByAssetType
us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty, us-gaap:DisposalGroupClassification
us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty, us-gaap:StatementGeographical, us-gaap:DisposalGroupClassification
us-gaap:StatementGeographical, us-gaap:DisposalGroupClassification
us-gaap:StatementGeographical, us-gaap:DisposalGroupClassification, us-gaap:LongLivedAssetsHeldForSaleByAssetType

cli:VariableInterestEntityEntityEstimatedFutureFundingCommitments

srt:RealEstateAndAccumulatedDepreciationAmountOfEncumbrances
us-gaap:MortgageLoansOnRealEstateDescriptionTypeOfProperty
us-gaap:MortgageLoansOnRealEstateDescriptionTypeOfProperty, us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty

us-gaap:AccountsPayableAndAccruedLiabilitiesCurrentAndNoncurrent
dei:LegalEntity

us-gaap:AccountsReceivableNet
dei:LegalEntity

us-gaap:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets

us-gaap:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedBuildings

us-gaap:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLand

us-gaap:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet

us-gaap:DebtInstrumentCarryingAmount
us-gaap:CreditFacility
us-gaap:CreditFacility, us-gaap:DebtInstrument
us-gaap:CreditFacility, us-gaap:SubsequentEventType
us-gaap:DebtInstrument
us-gaap:LongtermDebtType

us-gaap:DebtInstrumentFairValue

us-gaap:DebtInstrumentUnamortizedDiscount
us-gaap:LongtermDebtType

us-gaap:DebtInstrumentUnamortizedDiscountPremiumNet

us-gaap:DeferredCosts

us-gaap:DeferredCostsLeasingGross

us-gaap:DeferredFinanceCostsGross

us-gaap:DeferredRentReceivablesNet
dei:LegalEntity

us-gaap:DividendsPayableCurrentAndNoncurrent
dei:LegalEntity

us-gaap:DueFromJointVentures
us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:DueFromRelatedParties
us-gaap:AwardType
us-gaap:EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized
us-gaap:PlanName

us-gaap:EntityNotSubjectToIncomeTaxesDifferenceInBasesAmount

us-gaap:EscrowDeposit

us-gaap:FiniteLivedIntangibleAssetAcquiredInPlaceLeases

us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths
us-gaap:FiniteLivedIntangibleAssetsByMajorClass

us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseYearFive
us-gaap:FiniteLivedIntangibleAssetsByMajorClass

us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseYearFour
us-gaap:FiniteLivedIntangibleAssetsByMajorClass

us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseYearThree
us-gaap:FiniteLivedIntangibleAssetsByMajorClass

us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo
us-gaap:FiniteLivedIntangibleAssetsByMajorClass

us-gaap:FixturesAndEquipmentGross
dei:LegalEntity
dei:LegalEntity
us-gaap:GeneralPartnersCapitalAccount

us-gaap:InterestPayableCurrentAndNoncurrent
dei:LegalEntity

us-gaap:InvestmentBuildingAndBuildingImprovements
dei:LegalEntity

us-gaap:LandAndLandImprovements
us-gaap:DisposalGroupClassification
us-gaap:LandAvailableForSale
us-gaap:DisposalGroupClassification, us-gaap:LongLivedAssetsHeldForSaleByAssetType
us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty, us-gaap:DisposalGroupClassification
us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty, us-gaap:StatementGeographical, us-gaap:DisposalGroupClassification
us-gaap:StatementGeographical, us-gaap:DisposalGroupClassification
us-gaap:StatementGeographical, us-gaap:DisposalGroupClassification, us-gaap:LongLivedAssetsHeldForSaleByAssetType
us-gaap:Range
us-gaap:LesseeOperatingLeaseDiscountRate

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths

us-gaap:LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear

us-gaap:LessorOperatingLeasePaymentsToBeReceived

us-gaap:LessorOperatingLeasePaymentsToBeReceivedFiveYears

us-gaap:LessorOperatingLeasePaymentsToBeReceivedFourYears

us-gaap:LessorOperatingLeasePaymentsToBeReceivedNextTwelveMonths

us-gaap:LessorOperatingLeasePaymentsToBeReceivedRemainderOfFiscalYear

us-gaap:LessorOperatingLeasePaymentsToBeReceivedThereafter

us-gaap:LessorOperatingLeasePaymentsToBeReceivedThreeYears

us-gaap:LessorOperatingLeasePaymentsToBeReceivedTwoYears
dei:LegalEntity
us-gaap:LimitedPartnersCapitalAccount

us-gaap:LineOfCredit
dei:LegalEntity
us-gaap:ConsolidatedEntities, us-gaap:MortgageLoansOnRealEstateDescriptionTypeOfProperty, us-gaap:LossContingenciesByNatureOfContingency
us-gaap:CreditFacility
us-gaap:CreditFacility, us-gaap:DebtInstrument
us-gaap:CreditFacility, us-gaap:SubsequentEventType
us-gaap:MortgageLoansOnRealEstateDescriptionTypeOfProperty, us-gaap:LossContingenciesByNatureOfContingency
us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty

us-gaap:LoansAndLeasesReceivableNetReportedAmount
us-gaap:AccountsNotesLoansAndFinancingReceivableByReceivableType

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo

us-gaap:LongtermDebtWeightedAverageInterestRate
us-gaap:DebtInstrument

us-gaap:MinorityInterestInJointVentures

us-gaap:MinorityInterestInOperatingPartnerships
us-gaap:Ownership
us-gaap:MinorityInterestOwnershipPercentageByNoncontrollingOwners
us-gaap:CreditFacility, us-gaap:DebtInstrument
us-gaap:MortgageLoansOnRealEstate
us-gaap:MortgageLoansOnRealEstateDescriptionTypeOfProperty
us-gaap:MortgageLoansOnRealEstateDescriptionTypeOfProperty, us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName
us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty, us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName
us-gaap:AccountsNotesLoansAndFinancingReceivableByReceivableType
us-gaap:NotesReceivableGross
us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty, us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName, us-gaap:DisposalGroupClassification, us-gaap:SubsequentEventType
us-gaap:NumberOfRealEstateProperties
dei:LegalEntity
us-gaap:PartnersCapital
dei:LegalEntity, us-gaap:PartnerTypeOfPartnersCapitalAccount
us-gaap:PartnersCapitalAccountUnits
us-gaap:PartnerTypeOfPartnersCapitalAccount
dei:LegalEntity
us-gaap:PartnersCapitalAttributableToNoncontrollingInterest

us-gaap:PartnersCapitalIncludingPortionAttributableToNoncontrollingInterest
dei:LegalEntity
dei:LegalEntity, us-gaap:PartnerTypeOfPartnersCapitalAccount
us-gaap:PartnerTypeOfPartnersCapitalAccount

us-gaap:PrepaidExpenseAndOtherAssets

us-gaap:RealEstateAccumulatedDepreciation

us-gaap:RealEstateAndAccumulatedDepreciationCarryingAmountOfBuildingsAndImprovements

us-gaap:RealEstateAndAccumulatedDepreciationCarryingAmountOfLand

us-gaap:RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisitionCarryingCosts

us-gaap:RealEstateAndAccumulatedDepreciationInitialCostOfBuildingsAndImprovements

us-gaap:RealEstateAndAccumulatedDepreciationInitialCostOfLand

us-gaap:RealEstateGrossAtCarryingValue
us-gaap:MortgageLoansOnRealEstateDescriptionTypeOfProperty
us-gaap:RealEstateHeldforsale

us-gaap:RealEstateInvestmentPropertyAccumulatedDepreciation
dei:LegalEntity
us-gaap:DisposalGroupClassification
us-gaap:DisposalGroupClassification, us-gaap:LongLivedAssetsHeldForSaleByAssetType
us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty, us-gaap:DisposalGroupClassification
us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty, us-gaap:StatementGeographical, us-gaap:DisposalGroupClassification
us-gaap:StatementGeographical
us-gaap:StatementGeographical, us-gaap:DisposalGroupClassification
us-gaap:StatementGeographical, us-gaap:DisposalGroupClassification, us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations
us-gaap:StatementGeographical, us-gaap:DisposalGroupClassification, us-gaap:LongLivedAssetsHeldForSaleByAssetType

us-gaap:RealEstateInvestmentPropertyAtCost
dei:LegalEntity
us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty, us-gaap:StatementGeographical, us-gaap:DisposalGroupClassification
us-gaap:StatementGeographical
us-gaap:StatementGeographical, us-gaap:DisposalGroupClassification, us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations

us-gaap:RealEstateInvestmentPropertyNet
dei:LegalEntity

us-gaap:RedeemableNoncontrollingInterestEquityFairValue
dei:LegalEntity
dei:LegalEntity, us-gaap:StatementEquityComponents
us-gaap:ConsolidatedEntities, us-gaap:StatementEquityComponents
us-gaap:PreferredUnitsByName, us-gaap:StatementEquityComponents
us-gaap:StatementEquityComponents
dei:LegalEntity, us-gaap:StatementEquityComponents
us-gaap:RedeemableNoncontrollingInterestEquityOtherFairValue
us-gaap:StatementEquityComponents

us-gaap:RestrictedCashAndCashEquivalents
dei:LegalEntity

us-gaap:SecuredDebt
dei:LegalEntity

us-gaap:SecurityDeposit

us-gaap:SeniorNotes
dei:LegalEntity

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue
us-gaap:Range, us-gaap:RelatedPartyTransactionsByRelatedParty, us-gaap:StatementClassOfStock, us-gaap:SubsequentEventType
us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized
us-gaap:Range, us-gaap:RelatedPartyTransactionsByRelatedParty, us-gaap:StatementClassOfStock
us-gaap:SharePrice
us-gaap:StatementScenario, us-gaap:PlanName
us-gaap:TitleOfIndividual

us-gaap:SharebasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeExercisableOptionsWeightedAverageExercisePrice1
us-gaap:PlanName
us-gaap:Range, us-gaap:RelatedPartyTransactionsByRelatedParty, us-gaap:StatementClassOfStock, us-gaap:SubsequentEventType
us-gaap:SharesIssuedPricePerShare

us-gaap:TenantImprovements
dei:LegalEntity

us-gaap:VariableInterestEntityEntityMaximumLossExposureAmount

Plots across concepts


IncomeStatement
Comprehensive Income Net Of Tax
Balance Sheet
Goodwill
Assets
Cash And Cash Equivalents At Carrying Value
Current Assets
Cash And Cash Equivalents At Carrying Value
NonCurrent Assets
Goodwill
Liabilities
Dividends Payable Current And Noncurrent
Noncurrent Liabilities
Minority Interest
Stockholders Equity
Retained Earnings Accumulated Deficit
CashFlow
Net Cash Provided By Used In Financing Activities
NetCashProvidedByUsedInOperatingActivities
Net Income Loss
NetCashProvidedByUsedInInvestingActivities
Payments To Acquire Businesses Net Of Cash Acquired
NetCashProvidedByUsedInFinancingActivities
Net Cash Provided By Used In Financing Activities
Shares
Weighted Average Number Of Shares Outstanding Basic
DividendsAndRepurchase
Dividends Payable Current And Noncurrent
LesseeOperatingLeaseLiabilityPaymentsDue
Lessee Operating Lease Liability Payments Remainder Of Fiscal Year

Tables

  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
us-gaap:CommonStockValue █▇▇▇▆▆▆▆▆▄▄▄▄▃▂▂▂▁0.9090.9070.9070.9070.9060.9060.9060.9060.9060.9030.9030.9030.9020.9010.8990.8990.8990.898
 us-gaap:SharesOutstanding us-gaap:StatementEquityComponents us-gaap:CommonStock█▇▇▇▆▆▆▅▅▄▄▄▄▃▁▁▁▁90.94790.72990.71290.71290.59790.59690.59590.55290.55390.32690.3290.30790.28690.13689.91489.91489.91489.845
 us-gaap:CommonStockSharesOutstanding us-gaap:SubsequentEventType us-gaap:SubsequentEventNANANANANANANANANANANANANANANANANANA
us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding █▁99.87399.76NA100.307100.213100.183NA100.56100.523100.943NA100.712100.598100.604NA100.727100.37100.637
us-gaap:WeightedAverageNumberOfSharesOutstandingBasic █▁90.77490.692NA90.67190.62990.616NA90.58490.53390.498NA90.46890.3390.263NA90.02390.01189.955
us-gaap:EarningsPerShareBasic ▁▃▄▂▂▂▁▁▂█▄▃▃▄▃▃▂▃-0.810.060.67-0.49-0.41-0.47-0.64-0.65-0.432.670.45-0.05-0.050.45-0.010.39-0.440.11
us-gaap:EarningsPerShareDiluted ▁▃▄▂▂▂▁▁▂█▄▃▃▄▃▃▂▃-0.810.060.67-0.49-0.41-0.47-0.64-0.65-0.432.660.45-0.05-0.050.45-0.010.39-0.440.11
us-gaap:IncomeLossFromContinuingOperationsPerBasicShare ▁▂▃▁▂▂▄▁▂█▃▃▂▄-8.6e-07-2.8e-072.2e-07-8.4e-07-5.1e-07-4.1e-075.3e-07-6.4e-07-4.5000000000000003e-072.5899999999999998e-063.7e-07-1.2e-07-1.3e-074.2e-07NANANANA
 us-gaap:IncomeLossFromContinuingOperationsPerBasicShare dei:LegalEntity cli:MackCaliRealtyLp▁▂▃▁▂▂▄▁▂█▃▃▂▄-8.6e-07-2.8e-072.2e-07-8.4e-07-5.1e-07-4.1e-075.3e-07-6.4e-07-4.5000000000000003e-072.5899999999999998e-063.7e-07-1.2e-07-1.3e-074.2e-07NANANANA
us-gaap:IncomeLossFromContinuingOperationsPerDilutedShare ▁▂▃▁▂▂▄▁▂█▄▃▂▄-8.6e-07-2.8e-072.2e-07-8.4e-07-5.1e-07-4.1e-075.3e-07-6.4e-07-4.5000000000000003e-072.58e-063.7e-07-1.2e-07-1.3e-074.2e-07NANANANA
 us-gaap:IncomeLossFromContinuingOperationsPerDilutedShare dei:LegalEntity cli:MackCaliRealtyLp▁▂▃▁▂▂▄▁▂█▄▃▂▄-8.6e-07-2.8e-072.2e-07-8.4e-07-5.1e-07-4.1e-075.3e-07-6.4e-07-4.5000000000000003e-072.58e-063.7e-07-1.2e-07-1.3e-074.2e-07NANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
 COGS Ratio dei:LegalEntity cli:MackCaliRealtyLp▂▁▁▁▁▂▂▆▆▆▆▆▅▆▇█81.24776.09376.56477.6572.6582.05786.673131.884130.461134.249132.936132.114126.589138.967143.529160.018NANA
 Cost Ratio dei:LegalEntity cli:MackCaliRealtyLp▂▁▁▁▁▂▂▆▅▆▆▆▅▆▇██▇81.24776.09376.56477.6572.6582.05786.673131.884130.461134.249132.936132.114126.589138.967143.529160.018162.766149.887
 Margin from Continuing Operations dei:LegalEntity cli:MackCaliRealtyLp▂▁▁▁▁▂▂▆▅▆▆▆▅▆▇██▇81.24776.09376.56477.6572.6582.05786.673131.884130.461134.249132.936132.114126.589138.967143.529160.018162.766149.887
 Net profit Margin dei:LegalEntity cli:MackCaliRealtyLp▂▁▁▁▁▂▂▆▅▆▆▆▅▆▇██▇81.24776.09376.56477.6572.6582.05786.673131.884130.461134.249132.936132.114126.589138.967143.529160.018162.766149.887
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
us-gaap:ComprehensiveIncomeNetOfTax ▁▃▄▂▂▂▁▁▂█▃▃▃▄▃▃▂▃-72.0799.14765.632-42.208-34.887-39.906-54.837-56.719-26.218240.84739.34-1.160.35547.6576.74538.708-38.54320.979
 us-gaap:ComprehensiveIncomeNetOfTax dei:LegalEntity cli:MackCaliRealtyLp▁▃▄▂▂▂▁▁▂█▃▃▃▄▃▃▂▃-79.3048.38572.623-46.694-38.576-44.155-60.68-62.965-29.112268.11443.788-1.2910.39553.0647.52743.197-42.97923.401
us-gaap:ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest ▁▃▄▂▂▂▁▁▂█▃▃▃▄▃▃▂▃-74.03113.52178.298-41.118-32.934-37.86-55.613-56.899-24.953271.53347.5542.0433.28955.83310.05745.433-40.47823.956
 us-gaap:ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest dei:LegalEntity cli:MackCaliRealtyLp▁▃▄▂▂▂▁▁▂█▃▃▃▄▃▃▂▃-74.03113.52178.298-41.118-32.934-37.86-55.613-56.899-24.953271.53347.5542.0433.28955.83310.05745.433-40.47823.956
us-gaap:CostOfGoodsAndServicesSold ▁▃▁▂▁▃▁▄▃█3.1514.0923.1533.5983.1133.8533.2764.4024.0916.112NANANANANANANANA
us-gaap:CostsAndExpenses ▆▅▅█▆▆▁██▇█▇▇▇▇██▇100.94177.26672.055135.14593.83389.452-4.908129.65128.815118.137136.456114.61107.688118.801120.131130.814134.818125.09
us-gaap:GeneralAndAdministrativeExpense ▄▂▁█▃▃▃▁▃▁▁▁▂▃▂▂▁▁18.06713.98911.63628.94517.24215.81816.46112.05416.42712.59312.82811.6213.45516.08513.72613.1412.49111.592
us-gaap:IncomeLossFromContinuingOperations ▁▂▃▁▂▂▄▁▂█-78.907-20.22235.686-76.384-42.734-32.09162.131-54.464-22.479267.366NANANANANANANANA
 us-gaap:IncomeLossFromContinuingOperations dei:LegalEntity cli:MackCaliRealtyLp▁▂▃▁▂▂▄▁▂█-78.907-20.22235.686-76.384-42.734-32.09162.131-54.464-22.479267.366NANANANANANANANA
us-gaap:IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest ▁▂▃▁▂▂▄▁▂█▄▃▃▄▃▃▂▃-78.907-20.22235.686-76.384-42.734-32.09153.31-56.021-20.329275.59452.5231.6891.50150.6885.41144.703-39.12522.729
 us-gaap:IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest dei:LegalEntity cli:MackCaliRealtyLp▁▂▃▁▂▂▄▁▂█▄▃▃▄▃▃▂▃-78.907-20.22235.686-76.384-42.734-32.09153.31-56.021-20.329275.59452.5231.6891.50150.6885.41144.703-39.12522.729
us-gaap:InterestExpense ▁▂▃▄▄▄▃▆▆▇▆▅▃▄▆█▇▄16.55417.6119.19620.26520.61220.91818.8323.4523.51524.77423.58621.09418.99920.07522.4925.63424.94320.321
 us-gaap:InterestExpenseDebt us-gaap:CreditFacility,us-gaap:DebtInstrument us-gaap:SecuredDebt,cli:PortImperial45GarageDevelopmentNA0.8NANANANANANANANANANANANANANANANA
 us-gaap:InterestExpenseDebt us-gaap:CreditFacility,us-gaap:DebtInstrument us-gaap:SecuredDebt,cli:PortImperialFourAndFiveGarageDevelopmentNANA0.3NANANANANANANANANANANANANANANA
us-gaap:NetIncomeLoss ▁▃▄▂▂▂▁▁▂█▄▃▃▄▃▃▂▃-72.0797.62365.632-42.208-34.887-39.924-54.652-55.928-22.054244.49543.804-1.478-1.25143.0362.58238.054-37.3319.879
 us-gaap:NetIncomeLoss dei:LegalEntity cli:MackCaliRealtyLp▁▃▄▂▂▂▁▁▂█▄▃▃▄▃▃▂▃-79.3048.38572.623-46.694-38.576-44.139-60.475-62.087-24.488272.17548.757-1.645-1.39347.9192.88142.467-41.62622.174
us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic ▁▃▄▂▂▂▁▁▂█▄▃▃▄▃▃▂▃-73.6295.83261.025-44.375-37.123-42.728-57.601-58.953-38.813241.34341.178-4.144-4.6340.282-0.2335.326-39.88110.019
 us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic dei:LegalEntity cli:MackCaliRealtyLp▁▃▄▂▂▂▁▁▂█▄▃▃▄▃▃▂▃-81.0096.41567.525-49.091-41.049-47.239-63.738-65.446-43.097268.66645.834-4.613-5.15644.852-0.25739.423-44.47111.176
us-gaap:NetIncomeLossAvailableToCommonStockholdersDiluted ▁▃▄▂▂▂▁▁▂█▄▃▃▄▃▃▂▃-81.0096.41567.525-49.091-41.049-47.239-63.738-65.446-43.097268.66645.834-4.613-5.15644.852-0.25739.423-44.47111.176
 us-gaap:NetIncomeLossAvailableToCommonStockholdersDiluted dei:LegalEntity cli:MackCaliRealtyLp▁▃▄▂▂▂▁▁▂█▄▃▃▄▃▃▂▃-81.0096.41567.525-49.091-41.049-47.239-63.738-65.446-43.097268.66645.834-4.613-5.15644.852-0.25739.423-44.47111.176
us-gaap:OperatingCostsAndExpenses ▆▆▆▆▆▆▁█████▇█████19.0915.4517.67418.94215.63316.064-8.71827.23626.16124.96226.96227.10722.93925.61826.88426.31227.09227.091
us-gaap:OtherComprehensiveIncomeLossNetOfTax NANA0.00.00.0-0.016-0.205-0.878-4.624-4.451-4.9690.3541.7885.1454.6460.73-1.3531.227
 us-gaap:OtherComprehensiveIncomeLossNetOfTax dei:LegalEntity cli:MackCaliRealtyLpNANA0.00.00.0-0.016-0.205-0.878-4.624-4.451-4.9690.3541.7885.1454.6460.73-1.3531.227
 us-gaap:OtherComprehensiveIncomeLossNetOfTax dei:LegalEntity,us-gaap:PartnerTypeOfPartnersCapitalAccount cli:MackCaliRealtyLp,cli:LimitedPartnersCommonUnitholdersNANA0.00.00.0-0.034-0.02-0.087-0.46-0.413-0.5050.0360.182NANANANANA
 us-gaap:OtherComprehensiveIncomeLossNetOfTax dei:LegalEntity,us-gaap:StatementEquityComponents cli:MackCaliRealtyLp,us-gaap:AccumulatedOtherComprehensiveIncomeNANA0.00.00.00.018-0.185-0.791-4.164-3.648-4.4640.3181.6064.6214.1630.654-1.2131.1
 us-gaap:OtherComprehensiveIncomeLossNetOfTax us-gaap:PartnerTypeOfPartnersCapitalAccount cli:GeneralPartnerCommonUnitholdersNANANA0.00.00.018NA-0.791-4.164-4.038NA0.3181.6064.621NANANANA
 us-gaap:OtherComprehensiveIncomeLossNetOfTax us-gaap:StatementEquityComponents us-gaap:AccumulatedOtherComprehensiveIncomeNANA0.00.00.00.018-0.185-0.791-4.164-3.648-4.4640.3181.6064.6214.1630.654-1.2131.1
 us-gaap:OtherComprehensiveIncomeLossNetOfTax us-gaap:StatementEquityComponents us-gaap:NoncontrollingInterestNANA0.00.00.0-0.034-0.02-0.087-0.46-0.413-0.5050.0360.1820.5240.4830.076-0.140.127
us-gaap:ProfitLoss ▁▃▄▂▂▂▁▁▂█▄▃▃▃▃▃▂▃-74.03113.52178.298-41.118-32.934-37.844-55.408-56.021-20.329275.59452.5231.6891.50150.6885.41144.703-39.12522.729
 us-gaap:ProfitLoss dei:LegalEntity cli:MackCaliRealtyLp▁▃▄▂▂▂▁▁▂█▄▃▃▃▃▃▂▃-74.03113.52178.298-41.118-32.934-37.844-55.408-56.021-20.329275.59452.5231.6891.50150.6885.41144.703-39.12522.729
us-gaap:Revenues ▂▁▁▁▁▂▂▆▅▆▆▆▅▆▇██▇81.24776.09376.56477.6572.6582.05786.673131.884130.461134.249132.936132.114126.589138.967143.529160.018162.766149.887
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
us-gaap:Assets ▁▅▄▅▆▅▅█▆▅▄▄▃▂▃▄▄▃4591.4775160.3585147.7865190.7435360.0125285.5325292.7985720.9355327.7125274.2845060.6445046.1944858.2844815.6064957.8854995.5195076.4944914.227
us-gaap:Liabilities ▁▅▅▆▇▆▅█▄▄▅▅▄▄▅▅▆▄2564.1723055.5753042.1093155.2733257.5613146.893089.9413429.9572955.2922951.9223033.0043062.1132896.7532889.3693076.9543106.1753211.8422986.651
us-gaap:LiabilitiesAndStockholdersEquity ▁▅▄▅▆▅▅█▆▅▄▄▃▂▃▄▄▃4591.4775160.3585147.7865190.7435360.0125285.5325292.7985720.9355327.7125274.2845060.6445046.1944858.2844815.6064957.8854995.5195076.4944914.227
us-gaap:StockholdersEquity ▁▂▂▁▂▃▄▅▇█▄▄▄▄▄▄▄▅1335.2261406.8231398.8171336.121399.0331434.1431493.6991569.2611645.5871704.0181486.6581467.0441487.2471508.0911476.2951488.4661468.6691528.29
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
us-gaap:CashAndCashEquivalentsAtCarryingValue ▂█▂▁▁▁▁▂▂▁▂▁▂▁▁▃▁▅37.628261.68238.09622.87226.29525.26425.58934.76860.63812.06129.63310.82329.66425.30728.1888.78921.719168.316
us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents ▂█▂▁▁▁▁▂▂▁▂▁▂▂▂▄▂▆53.775280.51852.30237.37940.43941.12741.16654.40378.5332.62249.55430.94251.78560.13767.972129.26277.886225.912
 us-gaap:Land us-gaap:DisposalGroupClassification us-gaap:DisposalGroupHeldforsaleNotDiscontinuedOperations▁█27.327.9NA35.538.946.348.5NANANANANANANANANANANA
 us-gaap:Land us-gaap:DisposalGroupClassification,us-gaap:PropertyPlantAndEquipmentByType us-gaap:DisposalGroupHeldforsaleNotDiscontinuedOperations,cli:DevelopmentNANA31.90.50.50.50.5NANANANANANANANANANANA
 us-gaap:Land us-gaap:PropertyPlantAndEquipmentByType cli:Development▄▄▄▅▅▅▇▄█▁▁▁▄▄▄74.374.474.984.084.085.596.671.2108.849.649.649.671.772.677.0NANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
us-gaap:PropertyPlantAndEquipmentGross ██▇▆▅▃▂▁▄▁▁▃▅▆▅1149.4671127.9081098.5061039.32974.942915.333852.812786.693917.836792.967792.969914.1951004.8181065.7841019.403NANANA
us-gaap:InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures ▁▁▁▃▃▃▃▃▄▃▄▄▅▅▅▄██154.914159.971162.382194.779200.409202.574209.091213.499215.957212.961232.75230.614247.607249.513252.626238.44315.11325.15
us-gaap:Goodwill ██▁███▁███████████2.9452.9452.92.9452.9452.9452.92.9452.9452.9452.9452.9452.9452.9452.9452.9452.9452.945
 us-gaap:FiniteLivedIntangibleAssetsNet us-gaap:FiniteLivedIntangibleAssetsByMajorClass us-gaap:LeasesAcquiredInPlaceNANA31.589NANANANANANANANANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
us-gaap:LongTermDebt ▁▅▅▆▆▅▅█▄▄▅▅▄▃▅▅▆▄2359.2842821.9642801.7972895.8822990.4652877.1212808.5183169.552705.8962701.3452792.6512821.7932660.5172630.6142809.5682856.6762968.6992751.244
 us-gaap:SecuredLongTermDebt us-gaap:CreditFacility cli:TwentyTwentyOneCreditAgreementNANANANANANANANANANANANANANANANANANA
 us-gaap:SecuredLongTermDebt us-gaap:CreditFacility cli:TwentyTwentyOneTermLoanNANANANANANANANANANANANANANANANANANA
 us-gaap:SecuredLongTermDebt us-gaap:CreditFacility,us-gaap:SubsequentEventType cli:TwentyTwentyOneCreditAgreement,us-gaap:SubsequentEventNANANANANANANANANANANANANANANANANANA
 us-gaap:SecuredLongTermDebt us-gaap:CreditFacility,us-gaap:SubsequentEventType cli:TwentyTwentyOneTermLoan,us-gaap:SubsequentEventNANANANANANANANANANANANANANANANANANA
us-gaap:MinorityInterest ▁▂▃▂▃▄▄▆▇█▅▅▃▃▃▃▃▃175.107182.693193.563187.998194.463198.017205.776221.598230.461239.149210.523209.622190.069192.82192.428191.808189.957196.572
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo ▁▁█████1.7021.7021.751.751.751.751.75NANA1.75NANANANANANANANA
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree ▁▁█████1.7211.7211.7561.7561.7561.7561.756NANA1.756NANANANANANANANA
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFour ▁▁█████1.7281.7281.7761.7761.7761.7761.776NANA1.776NANANANANANANANA
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFive NANA1.742NANANA1.776NANANANANANANANANANANA
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive ▁▁▁████152.98152.98152.98154.722154.722154.722154.722NANA154.722NANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
us-gaap:StockholdersEquity ▁▂▂▁▂▃▄▅▇█▄▄▄▄▄▄▄▅1335.2261406.8231398.8171336.121399.0331434.1431493.6991569.2611645.5871704.0181486.6581467.0441487.2471508.0911476.2951488.4661468.6691528.29
us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest ▁▂▂▁▂▃▄▆▇█▄▄▄▄▄▄▃▄1510.3331589.5161592.381524.1181593.4961632.161699.4751790.8591876.0481943.1671697.1811676.6661677.3161700.9111668.7231680.2741658.6261724.862
us-gaap:CommonStockValue █▇▇▇▆▆▆▆▆▄▄▄▄▃▂▂▂▁0.9090.9070.9070.9070.9060.9060.9060.9060.9060.9030.9030.9030.9020.9010.8990.8990.8990.898
us-gaap:AdditionalPaidInCapital ▁▁▁▁▂▂▂▃▃▅▇▇▇█▇▇▇█2529.052528.572528.1872531.1222533.6862533.9092535.442538.0462539.5472553.6522561.5032563.1652564.1532567.32565.1362566.0692566.9972570.093
us-gaap:RetainedEarningsAccumulatedDeficit ▁▃▂▁▂▃▄▆▇█▃▃▃▄▃▃▃▄-1194.733-1122.654-1130.277-1195.909-1135.559-1100.672-1042.629-969.858-895.824-855.659-1084.518-1110.258-1090.724-1071.42-1096.429-1081.028-1101.099-1045.786
us-gaap:MinorityInterest ▁▂▃▂▃▄▄▆▇█▅▅▃▃▃▃▃▃175.107182.693193.563187.998194.463198.017205.776221.598230.461239.149210.523209.622190.069192.82192.428191.808189.957196.572
us-gaap:MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders NANA0.02.029-0.792.272.2882.362.3611.6962.2622.3642.1362.262.3342.3342.3141.647
 us-gaap:MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders dei:LegalEntity cli:MackCaliRealtyLpNANA0.020.171-0.7920.38920.40720.46620.47219.76120.32620.4220.18920.28720.31720.31720.29715.128
 us-gaap:MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders dei:LegalEntity,us-gaap:PartnerTypeOfPartnersCapitalAccount cli:MackCaliRealtyLp,cli:GeneralPartnerCommonUnitholdersNANA0.018.1420.018.11918.11918.10618.11118.06518.06418.05618.053NANANANANA
 us-gaap:MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders dei:LegalEntity,us-gaap:PartnerTypeOfPartnersCapitalAccount cli:MackCaliRealtyLp,cli:LimitedPartnersCommonUnitholdersNANA0.02.029-0.792.272.2882.362.3611.6962.2622.3642.136NANANANANA
 us-gaap:MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders us-gaap:PartnerTypeOfPartnersCapitalAccount cli:GeneralPartnerCommonUnitholdersNANANA18.1420.018.119NA18.10618.11118.065NA18.05618.05318.027NANANANA
 us-gaap:MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders us-gaap:StatementEquityComponents us-gaap:NoncontrollingInterestNANA0.02.029-0.792.272.2882.362.3611.6962.2622.3642.1362.262.3342.3342.3141.647
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
us-gaap:NetCashProvidedByUsedInOperatingActivities ▁▄▂▂▄▆▂▇▄▆▆▆▄█▅█▇▇1.79326.1548.8348.33424.59143.66310.93552.08722.78346.03740.81644.32125.03756.89933.52858.8552.44951.313
us-gaap:NetCashProvidedByUsedInInvestingActivities █▇▆▆▄▅▆▁▅▆▅▄▅▇▅▇▃▂300.129189.97111.427111.218-111.082-83.098120.006-512.759-52.2128.888-0.636-215.404-95.662143.548-22.68127.457-227.953-422.53
us-gaap:NetCashProvidedByUsedInFinancingActivities ▁▅▄▄▅▅▄▇▅▄▄▆▅▃▄▄▅█-528.66512.092-105.336-122.61285.80339.394-144.178436.54575.335-91.857-21.568150.2462.273-208.282-57.978-134.93127.478511.566
 us-gaap:NetCashProvidedByUsedInFinancingActivities dei:LegalEntity cli:MackCaliRealtyLp▁▅▄▄▅▅▄▇▅▄▄▆▅▃▄▄▅█-528.66512.092-105.336-122.61285.80339.394-144.178436.54575.335-91.857-21.568150.2462.273-208.282-57.978-134.93127.478511.566
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
us-gaap:AmortizationOfFinancingCosts NANA1.4671.0741.061.0241.1471.1211.1681.1891.4851.3021.1451.0961.151.1841.1751.103
us-gaap:DepreciationDepletionAndAmortization ▅▅▅▆▅▆▁▇▇▇▇▇▆▆▇▇█▇28.28627.11128.14730.75326.54132.904-16.01548.33648.5347.29445.3945.06740.33839.48945.61750.66856.05146.338
us-gaap:NetCashProvidedByUsedInOperatingActivities ▁▄▂▂▄▆▂▇▄▆▆▆▄█▅█▇▇1.79326.1548.8348.33424.59143.66310.93552.08722.78346.03740.81644.32125.03756.89933.52858.8552.44951.313
us-gaap:NetIncomeLoss ▁▃▄▂▂▂▁▁▂█▄▃▃▄▃▃▂▃-72.0797.62365.632-42.208-34.887-39.924-54.652-55.928-22.054244.49543.804-1.478-1.25143.0362.58238.054-37.3319.879
 us-gaap:NetIncomeLoss dei:LegalEntity cli:MackCaliRealtyLp▁▃▄▂▂▂▁▁▂█▄▃▃▄▃▃▂▃-79.3048.38572.623-46.694-38.576-44.139-60.475-62.087-24.488272.17548.757-1.645-1.39347.9192.88142.467-41.62622.174
us-gaap:ProfitLoss ▁▃▄▂▂▂▁▁▂█▄▃▃▃▃▃▂▃-74.03113.52178.298-41.118-32.934-37.844-55.408-56.021-20.329275.59452.5231.6891.50150.6885.41144.703-39.12522.729
 us-gaap:ProfitLoss dei:LegalEntity cli:MackCaliRealtyLp▁▃▄▂▂▂▁▁▂█▄▃▃▃▃▃▂▃-74.03113.52178.298-41.118-32.934-37.844-55.408-56.021-20.329275.59452.5231.6891.50150.6885.41144.703-39.12522.729
us-gaap:ShareBasedCompensation ██▆▁██▆▆▇▆▆▅▁█2.5432.5291.9430.7232.4392.532.111.982.1911.881.9351.770.6572.532NA2.1692.0461.053
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
us-gaap:NetCashProvidedByUsedInInvestingActivities █▇▆▆▄▅▆▁▅▆▅▄▅▇▅▇▃▂300.129189.97111.427111.218-111.082-83.098120.006-512.759-52.2128.888-0.636-215.404-95.662143.548-22.68127.457-227.953-422.53
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
us-gaap:NetCashProvidedByUsedInFinancingActivities ▁▅▄▄▅▅▄▇▅▄▄▆▅▃▄▄▅█-528.66512.092-105.336-122.61285.80339.394-144.178436.54575.335-91.857-21.568150.2462.273-208.282-57.978-134.93127.478511.566
 us-gaap:NetCashProvidedByUsedInFinancingActivities dei:LegalEntity cli:MackCaliRealtyLp▁▅▄▄▅▅▄▇▅▄▄▆▅▃▄▄▅█-528.66512.092-105.336-122.61285.80339.394-144.178436.54575.335-91.857-21.568150.2462.273-208.282-57.978-134.93127.478511.566
 us-gaap:RepaymentsOfLongTermDebt us-gaap:DebtInstrument,us-gaap:DisposalGroupClassification,us-gaap:SubsequentEventType cli:ShortHillsPortfolio,us-gaap:DisposalGroupHeldforsaleNotDiscontinuedOperations,us-gaap:SubsequentEventNANANANANANANANANANANANANANANANANANA
 us-gaap:RepaymentsOfLongTermDebt us-gaap:DisposalGroupClassification,us-gaap:SubsequentEventType us-gaap:DisposalGroupHeldforsaleNotDiscontinuedOperations,us-gaap:SubsequentEventNANANANANANANANANANANANANANANANANANA
 us-gaap:RepaymentsOfLongTermDebt us-gaap:StatementGeographical,us-gaap:DisposalGroupClassification,us-gaap:SubsequentEventType cli:ShortHillsNewJersey,us-gaap:DisposalGroupHeldforsaleNotDiscontinuedOperations,us-gaap:SubsequentEventNANANANANANANANANANANANANANANANANANA
us-gaap:PaymentsForRepurchaseOfCommonStock NANA0.5230.0290.02.141NANANANANANANANANANANANA
 us-gaap:PaymentsForRepurchaseOfCommonStock dei:LegalEntity cli:MackCaliRealtyLpNANA0.5230.0290.02.141NANANANANANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31

Common Stock Value

us-gaap:CommonStockValue

us-gaap:CommonStockValue


Common
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value909000.0907000.0907000.0907000.0906000.0906000.0906000.0906000.0906000.0903000.0903000.0903000.0902000.0901000.0899000.0899000.0899000.0898000.0897000.0897000.0897000.0896000.0896000.0893000.0892000.0891000.0891000.0891000.0890000.0886000.0882000.0880000.0880000.0879000.0875000.0878000.0878000.0878000.0878000.0871000.0871000.0869000.0796000.0789000.0
Percentage of CommonStockValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Shares Outstanding

us-gaap:SharesOutstanding us-gaap:StatementEquityComponents

us-gaap:SharesOutstanding

us-gaap:CommonStock


Shares
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302013-12-312012-12-312011-12-31
Value90909090909090909090909090908989898989898989898989898989888787
Percentage of SharesOutstanding100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Common Stock Shares Outstanding

us-gaap:CommonStockSharesOutstanding us-gaap:SubsequentEventType

us-gaap:CommonStockSharesOutstanding

us-gaap:SubsequentEvent


Common
Period End2020-07-132020-04-022020-01-032019-10-042019-07-022019-04-022019-01-032018-10-022018-07-032018-04-132018-01-032017-10-032017-07-062017-04-052017-01-052016-10-052016-07-062016-04-052016-01-062015-10-052015-01-06
Value909090909090909090908989898989898989898988
Percentage of CommonStockSharesOutstanding100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Weighted Average Number Of Diluted Shares Outstanding

us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding

us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding


Weighted
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-31
Value999910010010010010010010010010010010010010010010010010010010010099999999100100100999996929292
Percentage of WeightedAverageNumberOfDilutedSharesOutstanding100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Weighted Average Number Of Shares Outstanding Basic

us-gaap:WeightedAverageNumberOfSharesOutstandingBasic

us-gaap:WeightedAverageNumberOfSharesOutstandingBasic


Weighted
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-31
Value9090909090909090909090909089898989898989888888878787878787878682797978
Percentage of WeightedAverageNumberOfSharesOutstandingBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Earnings Per Share Basic

us-gaap:EarningsPerShareBasic

us-gaap:EarningsPerShareBasic


Earnings
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-0.810.060.67-0.49-0.41-0.47-0.64-0.65-0.432.670.45-0.05-0.050.45-0.010.39-0.440.110.17-0.10.540.69-0.35-1.420.4-0.03-0.10.020.58-0.17-0.620.050.260.13-0.110.160.110.290.180.240.20.190.090.160.240.18
Percentage of EarningsPerShareBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EarningsPerShareBasic dei:LegalEntity

cli:MackCaliRealtyLp


Earnings
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value-0.810.060.67-0.49-0.41-0.47-0.64-0.65-0.432.670.45-0.05-0.050.45-0.010.39-0.440.110.17-0.10.540.69-0.35-1.420.4-0.03
Percentage of EarningsPerShareBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Earnings Per Share Diluted

us-gaap:EarningsPerShareDiluted

us-gaap:EarningsPerShareDiluted


Earnings
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-0.810.060.67-0.49-0.41-0.47-0.64-0.65-0.432.660.45-0.05-0.050.45-0.010.39-0.440.110.17-0.10.540.69-0.35-1.420.4-0.03-0.10.020.58-0.17-0.620.050.260.13-0.110.160.110.290.180.240.20.190.090.160.240.18
Percentage of EarningsPerShareDiluted100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EarningsPerShareDiluted dei:LegalEntity

cli:MackCaliRealtyLp


Earnings
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value-0.810.060.67-0.49-0.41-0.47-0.64-0.65-0.432.660.45-0.05-0.050.45-0.010.39-0.440.110.17-0.10.540.69-0.35-1.420.4-0.03
Percentage of EarningsPerShareDiluted100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Income Loss From Continuing Operations Per Basic Share

us-gaap:IncomeLossFromContinuingOperationsPerBasicShare

us-gaap:IncomeLossFromContinuingOperationsPerBasicShare


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-0.86-0.280.22-0.84-0.51-0.410.53-0.64-0.452.590.37-0.12-0.130.42-0.10.020.58-0.17-0.6-0.44-0.120.11-0.050.160.120.250.180.240.20.190.090.160.190.18
Percentage of IncomeLossFromContinuingOperationsPerBasicShare100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncomeLossFromContinuingOperationsPerBasicShare dei:LegalEntity

cli:MackCaliRealtyLp


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value-0.86-0.280.22-0.84-0.51-0.410.53-0.64-0.452.590.37-0.12-0.130.42
Percentage of IncomeLossFromContinuingOperationsPerBasicShare100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Income Loss From Continuing Operations Per Diluted Share

us-gaap:IncomeLossFromContinuingOperationsPerDilutedShare

us-gaap:IncomeLossFromContinuingOperationsPerDilutedShare


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-0.86-0.280.22-0.84-0.51-0.410.53-0.64-0.452.580.37-0.12-0.130.42-0.10.020.58-0.17-0.6-0.44-0.120.11-0.050.160.120.250.180.240.20.190.090.160.190.18
Percentage of IncomeLossFromContinuingOperationsPerDilutedShare100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncomeLossFromContinuingOperationsPerDilutedShare dei:LegalEntity

cli:MackCaliRealtyLp


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value-0.86-0.280.22-0.84-0.51-0.410.53-0.64-0.452.580.37-0.12-0.130.42
Percentage of IncomeLossFromContinuingOperationsPerDilutedShare100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Comprehensive Income Net Of Tax

us-gaap:ComprehensiveIncomeNetOfTax

us-gaap:ComprehensiveIncomeNetOfTax


Comprehensive
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value-72.0799.14765-42.208-34.887-39.906-54.837-56.719-26.21824039-1.160.355476.74538-38.5432023-6.9974555-31.718-126.89235-2.521
Percentage of ComprehensiveIncomeNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues-88.712.085.7-54.4-48.0-48.6-63.3-43.0-20.1179.429.6-0.90.334.34.724.2-23.714.00.00.00.00.00.00.00.00.0

us-gaap:ComprehensiveIncomeNetOfTax dei:LegalEntity

cli:MackCaliRealtyLp


Comprehensive
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-30
Value-79.3048.38572-46.694-38.576-44.155-60.68-62.965-29.11226843-1.2910.395537.52743-42.9792326-7.8155163-35.513-142.422
Percentage of ComprehensiveIncomeNetOfTax110.091.7110.7110.6110.6110.6110.7111.0111.0111.3111.3111.3111.3111.3111.6111.6111.5111.5111.7111.7111.7113.0112.0112.2
Percentage of Revenues-97.611.094.9-60.1-53.1-53.8-70.0-47.7-22.3199.732.9-1.00.338.25.227.0-26.415.60.00.00.00.00.00.0
Percentage of Revenues cli:MackCaliRealtyLp-97.611.094.9-60.1-53.1-53.8-70.0-47.7-22.3199.732.9-1.00.338.25.227.0-26.415.60.00.00.00.00.00.0

Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest

us-gaap:ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest

us-gaap:ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest


Comprehensive
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value-74.0311378-41.118-32.934-37.86-55.613-56.899-24.953271472.0433.289551045-40.4782326-7.885162-35.975-142.14139-3.325
Percentage of ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues-91.117.8102.3-53.0-45.3-46.1-64.2-43.1-19.1202.335.81.52.640.27.028.4-24.916.00.00.00.00.00.00.00.00.0

us-gaap:ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest dei:LegalEntity

cli:MackCaliRealtyLp


Comprehensive
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-30
Value-74.0311378-41.118-32.934-37.86-55.613-56.899-24.953271472.0433.289551045-40.4782326-7.885162-35.975-142.141
Percentage of ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues-91.117.8102.3-53.0-45.3-46.1-64.2-43.1-19.1202.335.81.52.640.27.028.4-24.916.00.00.00.00.00.00.0
Percentage of Revenues cli:MackCaliRealtyLp-91.117.8102.3-53.0-45.3-46.1-64.2-43.1-19.1202.335.81.52.640.27.028.4-24.916.00.00.00.00.00.00.0

Cost Of Goods And Services Sold

us-gaap:CostOfGoodsAndServicesSold

us-gaap:CostOfGoodsAndServicesSold


Cost
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value3.1514.0923.1533.5983.1133.8533.2764.4024.0916.112
Percentage of CostOfGoodsAndServicesSold100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues3.95.44.14.64.34.73.83.33.14.6

us-gaap:CostOfGoodsAndServicesSold dei:LegalEntity

cli:MackCaliRealtyLp


Cost
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value3.1514.0923.1533.5983.1133.853-7.9157.8897.456109.0059.997.555129.34711
Percentage of CostOfGoodsAndServicesSold100.0100.0100.0100.0100.0100.0-241.6179.2182.3171.00.00.00.00.00.00.0
Percentage of Revenues3.95.44.14.64.34.7-9.16.05.77.86.87.66.09.06.57.2
Percentage of Revenues cli:MackCaliRealtyLp3.95.44.14.64.34.7-9.16.05.77.86.87.66.09.06.57.2

us-gaap:CostOfGoodsAndServicesSold us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty

cli:PortImperialSouthNine


Cost
Period End2020-09-30
Value11
Percentage of CostOfGoodsAndServicesSold305.7
Percentage of Revenues14.2
Percentage of Revenues cli:PortImperialSouthNine0.0

cli:TwentyFiveChristopherColumbus


Cost
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value34683219537282263
Percentage of CostOfGoodsAndServicesSold1106.91898.31040.85071.41156.9649.7540.21035.7
Percentage of Revenues45.688.044.6238.143.721.716.947.2
Percentage of Revenues cli:TwentyFiveChristopherColumbus0.00.00.00.00.00.00.00.0

cli:UptonAtShortHills


Cost
Period End2020-12-312020-09-30
Value9.42.9
Percentage of CostOfGoodsAndServicesSold298.180.6
Percentage of Revenues12.33.7
Percentage of Revenues cli:UptonAtShortHills0.00.0

Costs And Expenses

us-gaap:CostsAndExpenses

us-gaap:CostsAndExpenses


Costs
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value10077721359389-4.908129128118136114107118120130134125131129121125157285121126134125130156195177159139150129131127130122130136146145147137
Percentage of CostsAndExpenses100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues124.2101.594.1174.0129.2109.0-5.798.398.788.0102.686.885.185.583.781.782.883.50.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:CostsAndExpenses dei:LegalEntity

cli:MackCaliRealtyLp


Costs
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value10077721359389-4.908129128118136114107118120130134125131129121125157285121126
Percentage of CostsAndExpenses100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues124.2101.594.1174.0129.2109.0-5.798.398.788.0102.686.885.185.583.781.782.883.50.00.00.00.00.00.00.00.0
Percentage of Revenues cli:MackCaliRealtyLp124.2101.594.1174.0129.2109.0-5.798.398.788.0102.686.885.185.583.781.782.883.50.00.00.00.00.00.00.00.0

Gains Losses On Extinguishment Of Debt

us-gaap:GainsLossesOnExtinguishmentOfDebt dei:LegalEntity

us-gaap:GainsLossesOnExtinguishmentOfDebt

cli:MackCaliRealtyLp


Gains
Period End2021-06-302019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value-46.735-0.153-0.0980.5881.311-0.4610.00.0-10.289-0.1820.00.0-0.239-23.658-19.30212
Percentage of GainsLossesOnExtinguishmentOfDebt100.0100.0100.0100.0100.0100.00.00.0100.0100.00.00.0100.0100.0100.0100.0
Percentage of Revenues-57.5-0.2-0.10.51.0-0.30.00.0-7.4-0.10.00.0-0.20.00.00.0
Percentage of Revenues cli:MackCaliRealtyLp-57.5-0.2-0.10.51.0-0.30.00.0-7.4-0.10.00.0-0.20.00.00.0

General And Administrative Expense

us-gaap:GeneralAndAdministrativeExpense

us-gaap:GeneralAndAdministrativeExpense


General
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value18131128171516121612121113161313121112141212121311112312132210121312121211109.0038.6839.2268.6298.9398.9928.6588.414
Percentage of GeneralAndAdministrativeExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues22.218.415.237.323.719.319.09.112.69.49.68.810.611.69.68.27.77.70.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:GeneralAndAdministrativeExpense dei:LegalEntity

cli:BowStreetLlc


General
Period End2020-12-312020-09-30
Value0.06.1
Percentage of GeneralAndAdministrativeExpense0.021.1
Percentage of Revenues0.00.0
Percentage of Revenues cli:BowStreetLlc0.00.0

cli:MackCaliRealtyLp


General
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value1813112817151612161212111316131312111214121212131111
Percentage of GeneralAndAdministrativeExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.099.1100.0
Percentage of Revenues22.218.415.237.323.719.319.09.112.69.49.68.810.611.69.68.27.77.70.00.00.00.00.00.00.00.0
Percentage of Revenues cli:MackCaliRealtyLp22.218.415.237.323.719.319.09.112.69.49.68.810.611.69.68.27.77.70.00.00.00.00.00.00.00.0

Income Loss From Continuing Operations

us-gaap:IncomeLossFromContinuingOperations

us-gaap:IncomeLossFromContinuingOperations


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value-78.907-20.22235-76.384-42.734-32.09162-54.464-22.47926715-8.5414862-31.718-126.89235-2.521-9.241.98251-15.298-52.779-38.894-10.5699.889-6.796141122162017156.6271314
Percentage of IncomeLossFromContinuingOperations100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues-97.1-26.646.6-98.4-58.8-39.171.7-41.3-17.2199.20.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:IncomeLossFromContinuingOperations dei:LegalEntity

cli:MackCaliRealtyLp


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312016-12-312016-09-302015-12-312015-09-30
Value-78.907-20.22235-76.384-42.734-32.09162-54.464-22.47926716-9.54-35.513-142.422
Percentage of IncomeLossFromContinuingOperations100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0111.7111.7112.0112.2
Percentage of Revenues-97.1-26.646.6-98.4-58.8-39.171.7-41.3-17.2199.20.00.00.00.0
Percentage of Revenues cli:MackCaliRealtyLp-97.1-26.646.6-98.4-58.8-39.171.7-41.3-17.2199.20.00.00.00.0

Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest

us-gaap:IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest

us-gaap:IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-78.907-20.22235-76.384-42.734-32.09153-56.021-20.329275521.6891.501505.41144-39.1252216-9.6055468-35.975-142.14139-3.325-10.4132.08557-17.628-60.202-46.046-12.08611-4.464151225182420188.232151717
Percentage of IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues-97.1-26.646.6-98.4-58.8-39.161.5-42.5-15.6205.339.51.31.236.53.827.9-24.015.20.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest dei:LegalEntity

cli:MackCaliRealtyLp


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-30
Value-78.907-20.22235-76.384-42.734-32.09153-56.021-20.329275521.6891.501505.41144-39.1252216-9.6055468-35.975-142.141
Percentage of IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues-97.1-26.646.6-98.4-58.8-39.161.5-42.5-15.6205.339.51.31.236.53.827.9-24.015.20.00.00.00.00.00.0
Percentage of Revenues cli:MackCaliRealtyLp-97.1-26.646.6-98.4-58.8-39.161.5-42.5-15.6205.339.51.31.236.53.827.9-24.015.20.00.00.00.00.00.0

Interest Expense

us-gaap:InterestExpense

us-gaap:InterestExpense


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value16171920202018232324232118202225242022242224242426272727282931303129293031303131313135363739
Percentage of InterestExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues20.423.125.126.128.425.521.717.818.018.517.716.015.014.415.716.015.313.60.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:InterestExpense dei:LegalEntity

cli:MackCaliRealtyLp


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value1617192020201823232423211820222524202224222424242627
Percentage of InterestExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues20.423.125.126.128.425.521.717.818.018.517.716.015.014.415.716.015.313.60.00.00.00.00.00.00.00.0
Percentage of Revenues cli:MackCaliRealtyLp20.423.125.126.128.425.521.717.818.018.517.716.015.014.415.716.015.313.60.00.00.00.00.00.00.00.0

us-gaap:InterestExpense us-gaap:DerivativeInstrumentRisk, us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship, us-gaap:HedgingDesignation

us-gaap:InterestRateSwap, us-gaap:CashFlowHedging, us-gaap:DesignatedAsHedgingInstrument


Interest
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value1617202020232324211820
Percentage of InterestExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues20.423.126.128.425.517.818.018.516.015.014.4
Percentage of Revenues us-gaap:InterestRateSwap us-gaap:CashFlowHedging us-gaap:DesignatedAsHedgingInstrument0.00.00.00.00.00.00.00.00.00.00.0

Interest Expense Debt

us-gaap:InterestExpenseDebt us-gaap:CreditFacility, us-gaap:DebtInstrument

us-gaap:InterestExpenseDebt

us-gaap:SecuredDebt, cli:PortImperial45GarageDevelopment


Interest
Period End2021-03-31
Value800000.0
Percentage of InterestExpenseDebt100.0
Percentage of Revenues1.1
Percentage of Revenues us-gaap:SecuredDebt cli:PortImperial45GarageDevelopment0.0

us-gaap:SecuredDebt, cli:PortImperialFourAndFiveGarageDevelopment


Interest
Period End2020-12-31
Value300000.0
Percentage of InterestExpenseDebt0.0
Percentage of Revenues0.4
Percentage of Revenues us-gaap:SecuredDebt cli:PortImperialFourAndFiveGarageDevelopment0.0

Net Income Loss

us-gaap:NetIncomeLoss

us-gaap:NetIncomeLoss


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-72.0797.62365-42.208-34.887-39.924-54.652-55.928-22.05424443-1.478-1.251432.58238-37.331915-8.5414862-31.718-126.89235-2.521-9.241.98251-15.298-54.1794.6432311-9.227141025162017156.627131814
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues-88.710.085.7-54.4-48.0-48.7-63.1-42.4-16.9182.133.0-1.1-1.031.01.823.8-22.913.30.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:NetIncomeLoss dei:LegalEntity

cli:MackCaliRealtyLp


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value-79.3048.38572-46.694-38.576-44.139-60.475-62.087-24.48827248-1.645-1.393472.88142-41.6262216-9.545469-35.513-142.42239-2.835
Percentage of NetIncomeLoss110.0110.0110.7110.6110.6110.6110.7111.0111.0111.3111.3111.3111.4111.3111.6111.6111.5111.5111.7111.7111.7111.7112.0112.2112.4112.5
Percentage of Revenues-97.611.094.9-60.1-53.1-53.8-69.8-47.1-18.8202.736.7-1.2-1.134.52.026.5-25.614.80.00.00.00.00.00.00.00.0
Percentage of Revenues cli:MackCaliRealtyLp-97.611.094.9-60.1-53.1-53.8-69.8-47.1-18.8202.736.7-1.2-1.134.52.026.5-25.614.80.00.00.00.00.00.00.00.0

Net Income Loss Available To Common Stockholders Basic

us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic

us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value-73.6295.83261-44.375-37.123-42.728-57.601-58.953-38.81324141-4.144-4.6340-0.2335-39.8811015-8.5414862
Percentage of NetIncomeLossAvailableToCommonStockholdersBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues-90.67.779.7-57.1-51.1-52.1-66.5-44.7-29.8179.831.0-3.1-3.729.0-0.222.1-24.56.70.00.00.00.0

us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic dei:LegalEntity

cli:MackCaliRealtyLp


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value-81.0096.41567-49.091-41.049-47.239-63.738-65.446-43.09726845-4.613-5.15644-0.25739-44.4711116-9.545469
Percentage of NetIncomeLossAvailableToCommonStockholdersBasic110.0110.0110.7110.6110.6110.6110.7111.0111.0111.3111.3111.3111.4111.3111.7111.6111.5111.5111.7111.7111.7111.7
Percentage of Revenues-99.78.488.2-63.2-56.5-57.6-73.5-49.6-33.0200.134.5-3.5-4.132.3-0.224.6-27.37.50.00.00.00.0
Percentage of Revenues cli:MackCaliRealtyLp-99.78.488.2-63.2-56.5-57.6-73.5-49.6-33.0200.134.5-3.5-4.132.3-0.224.6-27.37.50.00.00.00.0

Net Income Loss Available To Common Stockholders Diluted

us-gaap:NetIncomeLossAvailableToCommonStockholdersDiluted

us-gaap:NetIncomeLossAvailableToCommonStockholdersDiluted


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value-81.0096.41567-49.091-41.049-47.239-63.738-65.446-43.09726845-4.613-5.15644-0.25739-44.4711116-9.545469-35.513-142.42239-2.835-10.3922.2357-17.306-61.5335.2772613-10.511161129182319187.7131521
Percentage of NetIncomeLossAvailableToCommonStockholdersDiluted100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues-99.78.488.2-63.2-56.5-57.6-73.5-49.6-33.0200.134.5-3.5-4.132.3-0.224.6-27.37.50.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:NetIncomeLossAvailableToCommonStockholdersDiluted dei:LegalEntity

cli:MackCaliRealtyLp


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-31
Value-81.0096.41567-49.091-41.049-47.239-63.738-65.446-43.09726845-4.613-5.15644-0.25739-44.47111-9.545469
Percentage of NetIncomeLossAvailableToCommonStockholdersDiluted100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues-99.78.488.2-63.2-56.5-57.6-73.5-49.6-33.0200.134.5-3.5-4.132.3-0.224.6-27.37.50.00.00.0
Percentage of Revenues cli:MackCaliRealtyLp-99.78.488.2-63.2-56.5-57.6-73.5-49.6-33.0200.134.5-3.5-4.132.3-0.224.6-27.37.50.00.00.0

Operating Costs And Expenses

us-gaap:OperatingCostsAndExpenses

us-gaap:OperatingCostsAndExpenses


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value191517181516-8.718272624262722252626272727252426292425282926272928252727282727263028283030272828
Percentage of OperatingCostsAndExpenses100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues23.520.323.124.421.519.6-10.120.720.118.620.320.518.118.418.716.416.618.10.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:OperatingCostsAndExpenses dei:LegalEntity

cli:MackCaliRealtyLp


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-30
Value191517181516-8.7182726242627222526262727272524262924
Percentage of OperatingCostsAndExpenses100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues23.520.323.124.421.519.6-10.120.720.118.620.320.518.118.418.716.416.618.10.00.00.00.00.00.0
Percentage of Revenues cli:MackCaliRealtyLp23.520.323.124.421.519.6-10.120.720.118.620.320.518.118.418.716.416.618.10.00.00.00.00.00.0

Other Comprehensive Income Loss Net Of Tax

us-gaap:OtherComprehensiveIncomeLossNetOfTax

us-gaap:OtherComprehensiveIncomeLossNetOfTax


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value000-16000.0-205000.0-878000.0-4624000.0-4451000.0-4969000.0354000.01788000.05145000.04646000.0730000.0-1353000.01227000.09744000.01725000.0-2913000.0-6340000.0
Percentage of OtherComprehensiveIncomeLossNetOfTax0.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues0.00.00.0-0.0-0.2-0.7-3.5-3.3-3.70.31.43.73.20.5-0.80.80.00.00.00.0

us-gaap:OtherComprehensiveIncomeLossNetOfTax dei:LegalEntity

cli:MackCaliRealtyLp


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-31
Value000-16000.0-205000.0-878000.0-4624000.0-4451000.0-4969000.0354000.01788000.05145000.04646000.0730000.0-1353000.01227000.09744000.0
Percentage of OtherComprehensiveIncomeLossNetOfTax0.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues0.00.00.0-0.0-0.2-0.7-3.5-3.3-3.70.31.43.73.20.5-0.80.80.0
Percentage of Revenues cli:MackCaliRealtyLp0.00.00.0-0.0-0.2-0.7-3.5-3.3-3.70.31.43.73.20.5-0.80.80.0

us-gaap:OtherComprehensiveIncomeLossNetOfTax dei:LegalEntity, us-gaap:PartnerTypeOfPartnersCapitalAccount

cli:MackCaliRealtyLp, cli:LimitedPartnersCommonUnitholders


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value000-34000.0-20000.0-87000.0-460000.0-413000.0-505000.036000.0182000.0
Percentage of OtherComprehensiveIncomeLossNetOfTax0.00.00.0212.59.89.99.99.310.210.210.2
Percentage of Revenues0.00.00.0-0.0-0.0-0.1-0.4-0.3-0.40.00.1
Percentage of Revenues cli:MackCaliRealtyLp cli:LimitedPartnersCommonUnitholders0.00.00.00.00.00.00.00.00.00.00.0

us-gaap:OtherComprehensiveIncomeLossNetOfTax dei:LegalEntity, us-gaap:StatementEquityComponents

cli:MackCaliRealtyLp, us-gaap:AccumulatedOtherComprehensiveIncome


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-31
Value00018000.0-185000.0-791000.0-4164000.0-3648000.0-4464000.0318000.01606000.04621000.04163000.0654000.0-1213000.01100000.08724000.0
Percentage of OtherComprehensiveIncomeLossNetOfTax0.00.00.0-112.590.290.190.182.089.889.889.889.889.689.689.789.689.5
Percentage of Revenues0.00.00.00.0-0.2-0.6-3.2-2.7-3.40.21.33.32.90.4-0.70.70.0
Percentage of Revenues cli:MackCaliRealtyLp us-gaap:AccumulatedOtherComprehensiveIncome0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:OtherComprehensiveIncomeLossNetOfTax us-gaap:PartnerTypeOfPartnersCapitalAccount

cli:GeneralPartnerCommonUnitholders


Other
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value0018000.0-791000.0-4164000.0-4038000.0318000.01606000.04621000.0
Percentage of OtherComprehensiveIncomeLossNetOfTax0.00.0-112.590.190.190.789.889.889.8
Percentage of Revenues0.00.00.0-0.6-3.2-3.00.21.33.3
Percentage of Revenues cli:GeneralPartnerCommonUnitholders0.00.00.00.00.00.00.00.00.0

us-gaap:OtherComprehensiveIncomeLossNetOfTax us-gaap:StatementEquityComponents

us-gaap:AccumulatedOtherComprehensiveIncome


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value00018000.0-185000.0-791000.0-4164000.0-3648000.0-4464000.0318000.01606000.04621000.04163000.0654000.0-1213000.01100000.08724000.01544000.0-2608000.0-5675000.0
Percentage of OtherComprehensiveIncomeLossNetOfTax0.00.00.0-112.590.290.190.182.089.889.889.889.889.689.689.789.689.589.589.589.5
Percentage of Revenues0.00.00.00.0-0.2-0.6-3.2-2.7-3.40.21.33.32.90.4-0.70.70.00.00.00.0
Percentage of Revenues us-gaap:AccumulatedOtherComprehensiveIncome0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:NoncontrollingInterest


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value000-34000.0-20000.0-87000.0-460000.0-413000.0-505000.036000.0182000.0524000.0483000.076000.0-140000.0127000.01020000.0181000.0-305000.0-665000.0
Percentage of OtherComprehensiveIncomeLossNetOfTax0.00.00.0212.59.89.99.99.310.210.210.210.210.410.410.310.410.510.510.510.5
Percentage of Revenues0.00.00.0-0.0-0.0-0.1-0.4-0.3-0.40.00.10.40.30.0-0.10.10.00.00.00.0
Percentage of Revenues us-gaap:NoncontrollingInterest0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Profit Loss

us-gaap:ProfitLoss

us-gaap:ProfitLoss


Profit
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-74.0311378-41.118-32.934-37.844-55.408-56.021-20.329275521.6891.501505.41144-39.1252216-9.6055468-35.975-142.14139-3.325-10.4132.08557-17.628-61.773.4392613-10.585161129182420188.232152217
Percentage of ProfitLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues-91.117.8102.3-53.0-45.3-46.1-63.9-42.5-15.6205.339.51.31.236.53.827.9-24.015.20.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:ProfitLoss dei:LegalEntity

cli:MackCaliRealtyLp


Profit
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value-74.0311378-41.118-32.934-37.844-55.408-56.021-20.329275521.6891.501505.41144-39.1252216-9.6055468-35.975-142.14139-3.325
Percentage of ProfitLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues-91.117.8102.3-53.0-45.3-46.1-63.9-42.5-15.6205.339.51.31.236.53.827.9-24.015.20.00.00.00.00.00.00.00.0
Percentage of Revenues cli:MackCaliRealtyLp-91.117.8102.3-53.0-45.3-46.1-63.9-42.5-15.6205.339.51.31.236.53.827.9-24.015.20.00.00.00.00.00.00.00.0

Revenues

us-gaap:Revenues

us-gaap:Revenues


Revenues
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value81767677728286131130134132132126138143160162149
Percentage of Revenues100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:Revenues dei:LegalEntity

cli:MackCaliRealtyLp


Revenuesdei:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value81767677728286131130134132132126138143160162149
Percentage of Revenues100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues cli:MackCaliRealtyLp100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:Revenues dei:LegalEntity, us-gaap:ProductOrService

cli:MackCaliRealtyLp, cli:RealEstateServices


Revenuesdei:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value2.5932.5272.7662.8762.7552.9933.093.4113.533.8423.9274.4324.0744.6615.1495.7485.7676.465
Percentage of Revenues3.23.33.63.73.83.63.62.62.72.93.03.43.23.43.63.63.54.3
Percentage of Revenues3.23.33.63.73.83.63.62.62.72.93.03.43.23.43.63.63.54.3
Percentage of Revenues cli:MackCaliRealtyLp cli:RealEstateServices100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:MackCaliRealtyLp, srt:Hotel


Revenuesdei:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value2.7141.0530.9970.8930.7721.6254.1393.3252.0940.283
Percentage of Revenues3.31.41.31.21.12.04.82.51.60.2
Percentage of Revenues3.31.41.31.21.12.04.82.51.60.2
Percentage of Revenues cli:MackCaliRealtyLp srt:Hotel100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:MackCaliRealtyLp, us-gaap:Parking


Revenuesdei:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value3.4843.0863.2724.0333.0345.2655.5875.7665.5634.9415.5345.4995.7575.3275.2235.766
Percentage of Revenues4.34.14.35.24.26.46.44.44.33.74.24.24.53.83.63.6
Percentage of Revenues4.34.14.35.24.26.46.44.44.33.74.24.24.53.83.63.6
Percentage of Revenues cli:MackCaliRealtyLp us-gaap:Parking100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:MackCaliRealtyLp, us-gaap:RealEstateOther


Revenuesdei:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value3.523.6562.2913.9991.2971.7241.8982.6662.492.1682.6052.2882.8733.2863.4263.476
Percentage of Revenues4.34.83.05.21.82.12.22.01.91.62.01.72.32.42.42.2
Percentage of Revenues4.34.83.05.21.82.12.22.01.91.62.01.72.32.42.42.2
Percentage of Revenues cli:MackCaliRealtyLp us-gaap:RealEstateOther100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:Revenues us-gaap:ProductOrService

cli:RealEstateServices


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value2.5932.5272.7662.8762.7552.9933.093.4113.533.8423.9274.4324.0744.6615.1495.7485.7676.465
Percentage of Revenues3.23.33.63.73.83.63.62.62.72.93.03.43.23.43.63.63.54.3
Percentage of Revenues3.23.33.63.73.83.63.62.62.72.93.03.43.23.43.63.63.54.3
Percentage of Revenues cli:RealEstateServices100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

srt:Hotel


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value2.7141.0530.9970.8930.7721.6254.1393.3252.0940.283
Percentage of Revenues3.31.41.31.21.12.04.82.51.60.2
Percentage of Revenues3.31.41.31.21.12.04.82.51.60.2
Percentage of Revenues srt:Hotel100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:Parking


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value3.4843.0863.2724.0333.0345.2655.5875.7665.5634.9415.5345.4995.7575.3275.2235.766
Percentage of Revenues4.34.14.35.24.26.46.44.44.33.74.24.24.53.83.63.6
Percentage of Revenues4.34.14.35.24.26.46.44.44.33.74.24.24.53.83.63.6
Percentage of Revenues us-gaap:Parking100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:RealEstateOther


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value3.523.6562.2913.9991.2971.7241.8982.6662.492.1682.6052.2882.8733.2863.4263.476
Percentage of Revenues4.34.83.05.21.82.12.22.01.91.62.01.72.32.42.42.2
Percentage of Revenues4.34.83.05.21.82.12.22.01.91.62.01.72.32.42.42.2
Percentage of Revenues us-gaap:RealEstateOther100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:Revenues us-gaap:StatementBusinessSegments

cli:MultipleFamilyRealEstateAndServicesSegment


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value403738373842434644363430242324242317
Percentage of Revenues49.649.049.848.552.652.250.035.234.327.125.723.419.617.217.315.414.711.6
Percentage of Revenues49.649.049.848.552.652.250.035.234.327.125.723.419.617.217.315.414.711.6
Percentage of Revenues cli:MultipleFamilyRealEstateAndServicesSegment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:RealEstateCommercialAndOtherSegment


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value413942383439-89.43784859898100101115118133138131
Percentage of Revenues51.051.355.449.347.848.2-103.264.265.473.074.476.180.482.982.583.784.888.0
Percentage of Revenues51.051.355.449.347.848.2-103.264.265.473.074.476.180.482.982.583.784.888.0
Percentage of Revenues cli:RealEstateCommercialAndOtherSegment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CorporateAndOther


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value-0.478-0.2950.6551.704-0.344-0.3390.4660.7260.381-0.17-0.1890.6830.016-0.0770.2951.450.9040.661
Percentage of Revenues-0.6-0.40.92.2-0.5-0.40.50.60.3-0.1-0.10.50.0-0.10.20.90.60.4
Percentage of Revenues-0.6-0.40.92.2-0.5-0.40.50.60.3-0.1-0.10.50.0-0.10.20.90.60.4
Percentage of Revenues us-gaap:CorporateAndOther100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Assets

us-gaap:Assets

us-gaap:Assets


Assets
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value45915160514751905360528552925720532752745060504648584815495749955076491442964435421342284063400141534198419243574354435445154609463845854526426942704299429543094326433043624721
Percentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:Assets dei:LegalEntity

cli:MackCaliRealtyLp


Assetsdei:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302015-12-31
Value459151605147519053605285529257205327527450605046485848154957499550764914429644354053
Percentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.099.8
Percentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.099.8
Percentage of Assets cli:MackCaliRealtyLp100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:Assets us-gaap:RelatedPartyTransactionsByRelatedParty

cli:RoselandResidentialL.p.


Assetsus-gaap:
Period End2020-12-312019-12-31
Value30002800
Percentage of Assets58.352.9
Percentage of Assets58.352.9
Percentage of Assets cli:RoselandResidentialL.p.100.0100.0

us-gaap:Assets us-gaap:StatementBusinessSegments

cli:MultipleFamilyRealEstateAndServicesSegment


Assetsus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-31
Value3304328132493265323931623079333228982440226022462036197919371287
Percentage of Assets72.063.663.162.960.459.858.258.254.446.344.744.541.941.139.130.0
Percentage of Assets72.063.663.162.960.459.858.258.254.446.344.744.541.941.139.130.0
Percentage of Assets cli:MultipleFamilyRealEstateAndServicesSegment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:RealEstateCommercialAndOtherSegment


Assetsus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302012-12-31
Value125716231881191221122091217823272369250926872734275127642915312534143760334433943165313631673197338436273636386137963891388639974382
Percentage of Assets27.431.536.536.839.439.641.240.744.547.653.154.256.657.458.862.667.376.577.876.575.174.277.979.981.586.486.788.687.289.486.186.796.8
Percentage of Assets27.431.536.536.839.439.641.240.744.547.653.154.256.657.458.862.667.376.577.876.575.174.277.979.981.586.486.788.687.289.486.186.796.8
Percentage of Assets cli:RealEstateCommercialAndOtherSegment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CorporateAndOther


Assetsus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-312015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302011-12-31
Value3025417128.3373235615932411265707210417547445223151802413531842859131216
Percentage of Assets0.74.90.30.20.20.60.71.11.16.12.21.31.41.52.13.51.11.11.30.53.51.85.37.74.00.61.30.30.30.4
Percentage of Assets0.74.90.30.20.20.60.71.11.16.12.21.31.41.52.13.51.11.11.30.53.51.85.37.74.00.61.30.30.30.4
Percentage of Assets us-gaap:CorporateAndOther100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Liabilities

us-gaap:Liabilities

us-gaap:Liabilities


Liabilities
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value25643055304231553257314630893429295529513033306228962889307631063211298625702721247824952379227022642334231024522438248325962598260225472457219121632160214121312104208523182578
Percentage of Liabilities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets55.859.259.160.860.859.558.460.055.556.059.960.759.660.062.162.263.360.859.861.458.859.058.656.754.555.655.156.356.057.057.556.456.155.654.351.350.750.249.949.548.648.153.154.6

us-gaap:Liabilities dei:LegalEntity

cli:MackCaliRealtyLp


Liabilitiesdei:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302015-12-31
Value256430553042315532573146308934292955295130333062289628893076310632112986257027212370
Percentage of Liabilities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.099.6
Percentage of Assets55.859.259.160.860.859.558.460.055.556.059.960.759.660.062.162.263.360.859.861.458.3
Percentage of Assets cli:MackCaliRealtyLp55.859.259.160.860.859.558.460.055.556.059.960.759.660.062.162.263.360.859.861.458.5

Liabilities And Stockholders Equity

us-gaap:LiabilitiesAndStockholdersEquity

us-gaap:LiabilitiesAndStockholdersEquity


Liabilities
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value45915160514751905360528552925720532752745060504648584815495749955076491442964435421342284063400141534198419243574354435445154609463845854526426942704299429543094326433043624721
Percentage of LiabilitiesAndStockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:LiabilitiesAndStockholdersEquity dei:LegalEntity

cli:MackCaliRealtyLp


Liabilities
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302015-12-31
Value459151605147519053605285529257205327527450605046485848154957499550764914429644354053
Percentage of LiabilitiesAndStockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.099.8
Percentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.099.8
Percentage of Assets cli:MackCaliRealtyLp100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Stockholders Equity

us-gaap:StockholdersEquity

us-gaap:StockholdersEquity


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value13351406139813361399143414931569164517041486146714871508147614881468152815271515153314991455149516331610162416441653160716421720174017411766182318481876188918981938195717581831
Percentage of StockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets29.127.327.225.726.127.128.227.430.932.329.429.130.631.329.829.828.931.135.534.236.435.535.837.439.338.338.837.738.036.936.437.337.538.039.042.743.343.744.044.044.845.240.338.8

us-gaap:StockholdersEquity us-gaap:PartnerTypeOfPartnersCapitalAccount

cli:GeneralPartnerCommonUnitholders


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value133514061398133613991434149315691645170414861467148715081476
Percentage of StockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets29.127.327.225.726.127.128.227.430.932.329.429.130.631.329.8
Percentage of Assets cli:GeneralPartnerCommonUnitholders0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Cash And Cash Equivalents At Carrying Value

us-gaap:CashAndCashEquivalentsAtCarryingValue

us-gaap:CashAndCashEquivalentsAtCarryingValue


Cash
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312008-12-312007-12-31
Value3726138222625253460122910292528882116831212911637301919291058058221308177245821192020151810211051402742912124
Percentage of CashAndCashEquivalentsAtCarryingValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.85.10.70.40.50.50.50.61.10.20.60.20.60.50.61.80.43.40.70.50.72.80.90.80.50.50.72.41.91.34.96.73.80.51.30.50.50.50.50.40.40.20.50.00.00.06.20.00.0

us-gaap:CashAndCashEquivalentsAtCarryingValue dei:LegalEntity

cli:MackCaliRealtyLp


Cash
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302014-12-312013-12-31
Value37261382226252534601229102925288821168312129116373029221
Percentage of CashAndCashEquivalentsAtCarryingValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.85.10.70.40.50.50.50.61.10.20.60.20.60.50.61.80.43.40.70.50.72.80.90.80.74.9
Percentage of Assets cli:MackCaliRealtyLp0.85.10.70.40.50.50.50.61.10.20.60.20.60.50.61.80.43.40.70.50.00.00.90.00.00.0

Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents


Cash
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312015-12-31
Value5328052374041415478324930516067129772258572
Percentage of CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets1.25.41.00.70.80.80.81.01.50.61.00.61.11.21.42.61.54.62.01.8

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents dei:LegalEntity

cli:MackCaliRealtyLp


Cash
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312015-12-31
Value5328052374041415478324930516067129772258572
Percentage of CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets1.25.41.00.70.80.80.81.01.50.61.00.61.11.21.42.61.54.62.01.8
Percentage of Assets cli:MackCaliRealtyLp1.25.41.00.70.80.80.81.01.50.61.00.61.11.21.42.61.54.62.01.8

Land

us-gaap:Land us-gaap:DisposalGroupClassification

us-gaap:Land

us-gaap:DisposalGroupHeldforsaleNotDiscontinuedOperations


Landus-gaap:
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-12-31
Value272735384648
Percentage of Land100.0100.0100.0100.0100.0100.0
Percentage of Assets0.60.50.70.70.90.9
Percentage of Assets us-gaap:DisposalGroupHeldforsaleNotDiscontinuedOperations0.00.00.00.00.00.0

us-gaap:Land us-gaap:DisposalGroupClassification, us-gaap:PropertyPlantAndEquipmentByType

us-gaap:DisposalGroupHeldforsaleNotDiscontinuedOperations, cli:Development


Landus-gaap:
Period End2020-12-312020-09-302020-06-302020-03-312019-12-31
Value310.50.50.50.5
Percentage of Land0.01.41.31.11.0
Percentage of Assets0.60.00.00.00.0
Percentage of Assets us-gaap:DisposalGroupHeldforsaleNotDiscontinuedOperations cli:Development0.00.00.00.00.0

us-gaap:Land us-gaap:PropertyPlantAndEquipmentByType

cli:Development


Landus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value7474748484859671108494949717277
Percentage of Land272.2266.70.0236.6215.9184.7199.20.00.00.00.00.00.00.00.0
Percentage of Assets1.61.41.51.61.61.61.81.22.00.91.01.01.51.51.6
Percentage of Assets cli:Development0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Property Plant And Equipment Gross

us-gaap:PropertyPlantAndEquipmentGross

us-gaap:PropertyPlantAndEquipmentGross


Property
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value1149112710981039974915852786917792792914100410651019
Percentage of PropertyPlantAndEquipmentGross100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets25.021.921.320.018.217.316.113.817.215.015.718.120.722.120.6

Investments In Affiliates Subsidiaries Associates And Joint Ventures

us-gaap:InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures

us-gaap:InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures


Investments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value154159162194200202209213215212232230247249252238315325320319315303303299284262247239265179181131135158132656463323132333435
Percentage of InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets3.43.13.23.83.73.84.03.74.14.04.64.65.15.25.14.86.26.67.47.27.57.27.57.56.86.25.95.56.14.14.02.92.93.52.91.51.51.50.70.70.80.80.80.8

us-gaap:InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures dei:LegalEntity

cli:MackCaliRealtyLp


Investments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302015-12-31
Value154159162194200202209213215212232230247249252238315325320319303
Percentage of InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets3.43.13.23.83.73.84.03.74.14.04.64.65.15.25.14.86.26.67.47.27.5
Percentage of Assets cli:MackCaliRealtyLp3.43.13.23.83.73.84.03.74.14.04.64.65.15.25.14.86.26.67.47.27.5

us-gaap:InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures us-gaap:ConsolidatedEntities

us-gaap:VariableInterestEntityPrimaryBeneficiary


Investments
Period End2020-12-31
Value109
Percentage of InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures67.1
Percentage of Assets2.1
Percentage of Assets us-gaap:VariableInterestEntityPrimaryBeneficiary0.0

us-gaap:InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures us-gaap:InvestmentsByConsolidatedAndNonconsolidatedEntities

us-gaap:VariableInterestEntityNotPrimaryBeneficiary


Investments
Period End2021-06-302021-03-312020-09-302020-06-302020-03-31
Value105108110112113
Percentage of InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures68.367.556.656.256.2
Percentage of Assets2.32.12.12.12.2
Percentage of Assets us-gaap:VariableInterestEntityNotPrimaryBeneficiary0.00.00.00.00.0

us-gaap:InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures us-gaap:MortgageLoansOnRealEstateDescriptionTypeOfProperty

cli:UnconsolidatedJointVentureOtherProperty


Investments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302015-12-31
Value154160162194200202209213216212232230247249252238315325320319303
Percentage of InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets3.43.13.23.83.73.84.03.74.14.04.64.65.15.25.14.86.26.67.47.27.5
Percentage of Assets cli:UnconsolidatedJointVentureOtherProperty0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures us-gaap:MortgageLoansOnRealEstateDescriptionTypeOfProperty, us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName

cli:UnconsolidatedJointVentureMultipleFamilyProperties, cli:CrystalHouseApartmentsInvestorsLLC


Investments
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302015-12-31
Value262828282828292929293030303130303028
Percentage of InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures13.814.214.113.813.513.313.812.712.711.912.112.113.09.89.59.69.59.3
Percentage of Assets0.50.50.50.50.50.50.60.60.60.60.60.60.60.60.60.70.70.7
Percentage of Assets cli:UnconsolidatedJointVentureMultipleFamilyProperties cli:CrystalHouseApartmentsInvestorsLLC0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

cli:UnconsolidatedJointVentureMultipleFamilyProperties, cli:MetropolitanAt40Park


Investments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value2.8513.1163.3473.7464.1724.3687.2577.3467.4817.6017.6796.4726.6036.7596.834
Percentage of InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures1.81.92.11.92.12.23.53.43.53.63.32.82.72.72.7
Percentage of Assets0.10.10.10.10.10.10.10.10.10.10.20.10.10.10.1
Percentage of Assets cli:UnconsolidatedJointVentureMultipleFamilyProperties cli:MetropolitanAt40Park0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

cli:UnconsolidatedJointVentureMultipleFamilyProperties, cli:PiNorthRiverwalk


Investments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value3637363535353535292723201816
Percentage of InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures23.623.322.818.517.917.016.616.413.911.710.18.17.26.7
Percentage of Assets0.80.70.70.70.70.70.60.70.60.50.50.40.40.3
Percentage of Assets cli:UnconsolidatedJointVentureMultipleFamilyProperties cli:PiNorthRiverwalk0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

cli:UnconsolidatedJointVentureMultipleFamilyProperties, cli:RiverparkAtHarrison


Investments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value0.5070.6040.6810.7870.890.9561.0151.0321.0751.2041.2721.3431.3921.5041.604
Percentage of InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures0.30.40.40.40.40.50.50.50.50.60.50.60.60.60.6
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of Assets cli:UnconsolidatedJointVentureMultipleFamilyProperties cli:RiverparkAtHarrison0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

cli:UnconsolidatedJointVentureMultipleFamilyProperties, cli:RivertraceAtPortImperial


Investments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value6.326.4726.6676.8087.0217.197.4637.5417.7327.9448.1128.3118.4818.6628.864
Percentage of InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures4.14.04.13.53.53.53.63.53.63.73.53.63.43.53.5
Percentage of Assets0.10.10.10.10.10.10.10.10.10.20.20.20.20.20.2
Percentage of Assets cli:UnconsolidatedJointVentureMultipleFamilyProperties cli:RivertraceAtPortImperial0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

cli:UnconsolidatedJointVentureMultipleFamilyProperties, cli:StationHouse


Investments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value333334333435353636373738383940
Percentage of InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures21.621.221.017.417.217.417.117.016.917.416.216.615.715.915.9
Percentage of Assets0.70.70.70.70.60.70.70.60.70.70.70.80.80.80.8
Percentage of Assets cli:UnconsolidatedJointVentureMultipleFamilyProperties cli:StationHouse0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

cli:UnconsolidatedJointVentureMultipleFamilyProperties, cli:UrbyAtHarborside


Investments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value697072747778798082838587899294
Percentage of InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures44.644.344.838.438.538.838.237.838.039.236.738.036.337.137.4
Percentage of Assets1.51.41.41.41.41.51.51.41.51.61.71.71.91.91.9
Percentage of Assets cli:UnconsolidatedJointVentureMultipleFamilyProperties cli:UrbyAtHarborside0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

cli:UnconsolidatedJointVentureOfficeBuildings, cli:OfficesAtCrystalLake


Investments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value3.613.6263.7443.6683.5953.5413.5213.5073.4713.4873.4423.4253.3893.3953.369
Percentage of InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures2.32.32.31.91.81.71.71.61.61.61.51.51.41.41.3
Percentage of Assets0.10.10.10.10.10.10.10.10.10.10.10.10.10.10.1
Percentage of Assets cli:UnconsolidatedJointVentureOfficeBuildings cli:OfficesAtCrystalLake0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

cli:UnconsolidatedJointVentureOfficeBuildings, cli:TwelveVreelandAssociatesLLC


Investments
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302015-12-31
Value1.8111.8114.1964.1043.9573.8467.37.1767.0647.0196.8916.7716.7926.7346.5546.3686.3156.2376.1575.89
Percentage of InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures1.11.12.22.02.01.83.43.33.33.03.02.72.72.72.72.01.91.91.91.9
Percentage of Assets0.00.00.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.1
Percentage of Assets cli:UnconsolidatedJointVentureOfficeBuildings cli:TwelveVreelandAssociatesLLC0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

cli:UnconsolidatedJointVentureOtherProperty, cli:OtherJointVentures


Investments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302015-12-31
Value0.3470.3470.3470.10.5690.5290.7290.080.8970.5511.321.1361.9231.3561.5950.981.7950.8791.0050.8113.506
Percentage of InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures0.20.20.20.10.30.30.30.00.40.30.60.50.80.50.60.40.60.30.30.31.2
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.1
Percentage of Assets cli:UnconsolidatedJointVentureOtherProperty cli:OtherJointVentures0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures us-gaap:StatementBusinessSegments

cli:MultipleFamilyRealEstateAndServicesSegment


Investments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-31
Value151154156186192195201202204202218216232234237238
Percentage of InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures97.796.696.696.096.296.396.594.994.994.994.094.193.894.093.974.5
Percentage of Assets3.33.03.03.63.63.73.83.53.83.84.34.34.84.94.85.6
Percentage of Assets cli:MultipleFamilyRealEstateAndServicesSegment4.64.74.85.75.96.26.66.17.18.39.79.711.411.912.218.5

cli:RealEstateCommercialAndOtherSegment


Investments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312012-12-31
Value3.615.4375.5557.8647.6997.4987.367101010131315141514858381807878767677798182116535369
Percentage of InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures2.33.43.44.03.83.73.55.14.95.05.95.86.15.96.06.127.125.625.525.224.825.725.125.627.430.233.034.243.929.729.352.8
Percentage of Assets0.10.10.10.20.10.10.10.20.20.20.30.30.30.30.30.31.71.71.91.81.91.81.91.91.91.91.91.92.71.21.21.5
Percentage of Assets cli:RealEstateCommercialAndOtherSegment0.30.30.30.40.40.40.30.50.40.40.50.50.50.50.50.52.52.22.42.42.52.52.42.42.32.22.22.13.11.41.41.6

Goodwill

us-gaap:Goodwill

us-gaap:Goodwill


Goodwill
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302012-12-31
Value2945000.02945000.02900000.02945000.02945000.02945000.02900000.02945000.02945000.02945000.02945000.02945000.02945000.02945000.02945000.02945000.02945000.02945000.02945000.02945000.02945000.02945000.02945000.02945000.02945000.02945000.02945000.02945000.02945000.02945000.02945000.02945000.02945000.0
Percentage of Goodwill100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.1

Finite Lived Intangible Assets Net

us-gaap:FiniteLivedIntangibleAssetsNet us-gaap:FiniteLivedIntangibleAssetsByMajorClass

us-gaap:FiniteLivedIntangibleAssetsNet

us-gaap:LeasesAcquiredInPlace


Finite
Period End2020-12-31
Value31
Percentage of FiniteLivedIntangibleAssetsNet100.0
Percentage of Assets0.6
Percentage of Assets us-gaap:LeasesAcquiredInPlace0.0

Other Assets

us-gaap:OtherAssets

us-gaap:OtherAssets


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value173192199220237250275261258594355340310306342439316308267303253220213200197210204320266228218284214208204206201211210217213211212213
Percentage of OtherAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets3.83.73.94.24.44.75.24.64.911.37.06.86.46.46.98.86.26.36.26.86.05.25.35.04.85.04.97.46.15.34.86.24.64.54.54.84.74.94.95.14.94.94.94.5

us-gaap:OtherAssets dei:LegalEntity

cli:MackCaliRealtyLp


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302015-12-31
Value173192199220237250275261258594355340310306342439316308267303203
Percentage of OtherAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.095.5
Percentage of Assets3.83.73.94.24.44.75.24.64.911.37.06.86.46.46.98.86.26.36.26.85.0
Percentage of Assets cli:MackCaliRealtyLp3.83.73.94.24.44.75.24.64.911.37.06.86.46.46.98.86.26.36.26.85.0

us-gaap:OtherAssets us-gaap:DisposalGroupClassification

us-gaap:SegmentDiscontinuedOperations


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-31
Value5.7274250676868
Percentage of OtherAssets3.314.221.322.928.527.424.9
Percentage of Assets0.10.50.81.01.31.31.3
Percentage of Assets us-gaap:SegmentDiscontinuedOperations0.00.00.00.00.00.00.0

Long Term Debt

us-gaap:LongTermDebt

us-gaap:LongTermDebt


Long
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-12-31
Value235928212801289529902877280831692705270127922821266026302809285629682751234024742274228121542043203421072088223822082232236223682369229622041970192919401914188618692089
Percentage of LongTermDebt100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets51.454.754.455.855.854.453.155.450.851.255.255.954.854.656.757.258.556.054.555.854.053.953.051.149.050.249.851.450.751.352.351.451.150.148.746.145.245.144.643.843.247.9

us-gaap:LongTermDebt us-gaap:DebtInstrument

cli:FixedRateDebtAndOtherObligations


Long
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value1678237423742333233123322298282825492519249322962166216624432632259320981875221220202089186218651895192719282043204320812282228922907572127
Percentage of LongTermDebt71.184.284.780.678.081.181.989.394.293.389.381.481.482.487.092.187.476.380.289.488.891.686.491.393.191.592.391.392.693.396.696.696.733.096.5
Percentage of Assets36.646.046.145.043.544.143.449.447.947.849.345.544.645.049.352.751.142.743.749.948.049.445.846.645.645.946.046.946.947.850.649.749.416.547.0
Percentage of Assets cli:FixedRateDebtAndOtherObligations0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

cli:RevolvingCreditFacilityAndOtherVariableRateMortgageDebt


Long
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value680447427562658545509340156181314525494464382224375652481261254197292177139179159195164150807978153877
Percentage of LongTermDebt28.915.815.319.422.018.918.110.75.86.711.318.618.617.613.67.912.623.720.610.611.28.713.68.76.98.57.78.77.46.73.43.43.367.03.5
Percentage of Assets14.88.78.310.812.310.39.66.02.93.46.210.410.29.67.74.57.413.311.25.96.04.77.24.43.44.33.84.53.83.51.81.71.733.61.7
Percentage of Assets cli:RevolvingCreditFacilityAndOtherVariableRateMortgageDebt0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:LongTermDebt us-gaap:LongtermDebtType

us-gaap:UnsecuredDebt


Long
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-31
Value572572572572571571571570570570570569569569818818817817951106410641263
Percentage of LongTermDebt20.320.419.819.119.920.318.021.121.120.420.221.421.620.328.727.629.734.938.446.846.758.6
Percentage of Assets11.111.111.010.710.810.810.010.710.811.311.311.711.811.516.416.116.619.021.425.325.231.1
Percentage of Assets us-gaap:UnsecuredDebt0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Secured Long Term Debt

us-gaap:SecuredLongTermDebt us-gaap:CreditFacility

us-gaap:SecuredLongTermDebt

cli:TwentyTwentyOneCreditAgreement


Secured
Period End2021-05-06
Value250
Percentage of SecuredLongTermDebt100.0
Percentage of Assets0.0
Percentage of Assets cli:TwentyTwentyOneCreditAgreement0.0

cli:TwentyTwentyOneTermLoan


Secured
Period End2021-05-06
Value150
Percentage of SecuredLongTermDebt60.0
Percentage of Assets0.0
Percentage of Assets cli:TwentyTwentyOneTermLoan0.0

us-gaap:SecuredLongTermDebt us-gaap:CreditFacility, us-gaap:SubsequentEventType

cli:TwentyTwentyOneCreditAgreement, us-gaap:SubsequentEvent


Secured
Period End2021-05-06
Value250
Percentage of SecuredLongTermDebt100.0
Percentage of Assets0.0
Percentage of Assets cli:TwentyTwentyOneCreditAgreement us-gaap:SubsequentEvent0.0

cli:TwentyTwentyOneTermLoan, us-gaap:SubsequentEvent


Secured
Period End2021-05-06
Value150
Percentage of SecuredLongTermDebt60.0
Percentage of Assets0.0
Percentage of Assets cli:TwentyTwentyOneTermLoan us-gaap:SubsequentEvent0.0

Minority Interest

us-gaap:MinorityInterest

us-gaap:MinorityInterest


Minority
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value175182193187194198205221230239210209190192192191189196199198200233228235255254257259262263276290294295301254258262264280283288285311
Percentage of MinorityInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets3.83.53.83.63.63.73.93.94.34.54.24.23.94.03.93.83.74.04.64.54.85.55.65.96.26.16.16.06.06.16.16.36.36.46.76.06.06.16.26.56.66.76.56.6

us-gaap:MinorityInterest us-gaap:StatementEquityComponents

us-gaap:NoncontrollingInterest


Minority
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302013-12-31
Value175182193187194198205221230239210209190192192191189196199198200233228235255254257259262276
Percentage of MinorityInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets3.83.53.83.63.63.73.93.94.34.54.24.23.94.03.93.83.74.04.64.54.85.55.65.96.26.16.16.06.06.1
Percentage of Assets us-gaap:NoncontrollingInterest0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Lessee Operating Lease Liability Payments Due Year Two

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo


Lessee
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-03-31
Value1702000.01702000.01750000.01750000.01750000.01750000.01750000.01750000.0
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearTwo100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.00.00.00.00.00.00.00.0

Lessee Operating Lease Liability Payments Due Year Three

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree


Lessee
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-03-31
Value1721000.01721000.01756000.01756000.01756000.01756000.01756000.01756000.0
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearThree100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.00.00.00.00.00.00.00.0

Lessee Operating Lease Liability Payments Due Year Four

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFour

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFour


Lessee
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-03-31
Value1728000.01728000.01776000.01776000.01776000.01776000.01776000.01776000.0
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearFour100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.00.00.00.00.00.00.00.0

Lessee Operating Lease Liability Payments Due Year Five

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFive

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFive


Lessee
Period End2020-12-312019-12-31
Value1742000.01776000.0
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearFive100.0100.0
Percentage of Assets0.00.0

Lessee Operating Lease Liability Payments Due After Year Five

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive


Lessee
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-03-31
Value152152152154154154154154
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets3.33.03.03.02.92.92.92.9

Operating Lease Liability

us-gaap:OperatingLeaseLiability

us-gaap:OperatingLeaseLiability


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value1371372323232323232323
Percentage of OperatingLeaseLiability100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets3.02.70.50.50.40.40.40.40.40.5

us-gaap:OperatingLeaseLiability us-gaap:AdjustmentsForNewAccountingPronouncements

us-gaap:AccountingStandardsUpdate201602


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-30
Value222222222223232222
Percentage of OperatingLeaseLiability16.316.294.595.095.1100.1100.294.394.8
Percentage of Assets0.50.40.40.40.40.50.40.40.4
Percentage of Assets us-gaap:AccountingStandardsUpdate2016020.00.00.00.00.00.00.00.00.0

Lessee Operating Lease Liability Payments Due

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDue

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDue


Lessee
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-03-31
Value160161161162162163163163
Percentage of LesseeOperatingLeaseLiabilityPaymentsDue100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets3.53.13.13.13.03.13.13.1

Lessee Operating Lease Liability Undiscounted Excess Amount

us-gaap:LesseeOperatingLeaseLiabilityUndiscountedExcessAmount

us-gaap:LesseeOperatingLeaseLiabilityUndiscountedExcessAmount


Lessee
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-03-31
Value2323138138138139139139
Percentage of LesseeOperatingLeaseLiabilityUndiscountedExcessAmount100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.50.52.72.72.62.62.62.6

Stockholders Equity

us-gaap:StockholdersEquity

us-gaap:StockholdersEquity


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value13351406139813361399143414931569164517041486146714871508147614881468152815271515153314991455149516331610162416441653160716421720174017411766182318481876188918981938195717581831
Percentage of StockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets29.127.327.225.726.127.128.227.430.932.329.429.130.631.329.829.828.931.135.534.236.435.535.837.439.338.338.837.738.036.936.437.337.538.039.042.743.343.744.044.044.845.240.338.8

us-gaap:StockholdersEquity us-gaap:PartnerTypeOfPartnersCapitalAccount

cli:GeneralPartnerCommonUnitholders


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value133514061398133613991434149315691645170414861467148715081476
Percentage of StockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets29.127.327.225.726.127.128.227.430.932.329.429.130.631.329.8
Percentage of Assets cli:GeneralPartnerCommonUnitholders0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Stockholders Equity Including Portion Attributable To Noncontrolling Interest

us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest

us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-312008-12-312007-12-31
Value1510158915921524159316321699179018761943169716761677170016681680165817241726171317341732168317301889186418821904191518711918201020352037206820782106213921542178222222452043214319592100
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets32.930.830.929.429.730.932.131.335.236.833.533.234.535.333.733.632.735.140.238.641.241.041.443.345.544.444.943.744.043.042.543.643.944.445.748.749.349.850.150.551.451.946.945.40.00.0

us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest us-gaap:StatementEquityComponents

us-gaap:AdditionalPaidInCapital


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-312008-12-312007-12-31
Value2529252825282531253325332535253825392553256125632564256725652566256625702576257425732571257025652562256125602556255425462539253625352533253025382538253725362521251825142292227519051886
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest167.4159.1158.8166.1159.0155.2149.2141.7135.4131.4150.9152.9152.9150.9153.7152.7154.8149.0149.2150.2148.3148.4152.7148.2135.6137.4136.0134.3133.4136.1132.4126.2124.6124.3122.3122.2120.5118.6117.7115.7113.3112.0112.2106.297.289.8
Percentage of Assets55.149.049.148.847.347.947.944.447.748.450.650.852.853.351.751.450.652.360.058.161.160.863.364.161.761.061.158.758.758.556.255.054.755.255.959.559.459.059.058.558.258.152.648.20.00.0
Percentage of Assets us-gaap:AdditionalPaidInCapital0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:CommonStock


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-312008-12-312007-12-31
Value0.9090.9070.9070.9070.9060.9060.9060.9060.9060.9030.9030.9030.9020.9010.8990.8990.8990.8980.8970.8970.8970.8960.8960.8930.8920.8910.8910.8910.890.8860.8820.880.880.8790.8750.8780.8780.8780.8780.8710.8710.8690.7960.7890.6640.656
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest0.10.10.10.10.10.10.10.10.00.00.10.10.10.10.10.10.10.10.10.10.10.10.10.10.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of Assets us-gaap:CommonStock0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:NoncontrollingInterest


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-312008-12-312007-12-31
Value175182193187194198205221230239210209190192192191189196199198200233228235255254257259262263276290294295301254258262264280283288285311414457
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest11.611.512.212.312.212.112.112.412.312.312.412.511.311.311.511.411.511.411.611.611.613.513.513.613.613.613.713.613.714.114.414.414.514.514.612.212.312.312.312.912.812.814.014.521.221.8
Percentage of Assets3.83.53.83.63.63.73.93.94.34.54.24.23.94.03.93.83.74.04.64.54.85.55.65.96.26.16.16.06.06.16.16.36.36.46.76.06.06.16.26.56.66.76.56.60.00.0
Percentage of Assets us-gaap:NoncontrollingInterest0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:RetainedEarnings


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-312008-12-312007-12-31
Value-1194.733-1122.654-1130.277-1195.909-1135.559-1100.672-1042.629-969.858-895.824-855.659-1084.518-1110.258-1090.724-1071.42-1096.429-1081.028-1101.099-1045.786-1052.184-1053.91-1031.922-1066.867-1115.612-1070.456-930.167-952.183-936.293-913.389-902.036-939.837-897.849-817.387-795.7-792.446-764.522-715.903-690.664-661.246-647.498-624.11-605.396-583.556-560.165-470.047-386.587-269.521
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest-79.1-70.6-71.0-78.5-71.3-67.4-61.4-54.2-47.8-44.0-63.9-66.2-65.0-63.0-65.7-64.3-66.4-60.6-60.9-61.5-59.5-61.6-66.3-61.8-49.2-51.1-49.7-48.0-47.1-50.2-46.8-40.7-39.1-38.9-37.0-34.4-32.8-30.9-30.1-28.6-27.2-26.0-27.4-21.9-19.7-12.8
Percentage of Assets-26.0-21.8-22.0-23.0-21.2-20.8-19.7-17.0-16.8-16.2-21.4-22.0-22.5-22.2-22.1-21.6-21.7-21.3-24.5-23.8-24.5-25.2-27.5-26.7-22.4-22.7-22.3-21.0-20.7-21.6-19.9-17.7-17.2-17.3-16.9-16.8-16.2-15.4-15.1-14.5-14.0-13.5-12.8-10.00.00.0
Percentage of Assets us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Common Stock Value

us-gaap:CommonStockValue

us-gaap:CommonStockValue


Common
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value909000.0907000.0907000.0907000.0906000.0906000.0906000.0906000.0906000.0903000.0903000.0903000.0902000.0901000.0899000.0899000.0899000.0898000.0897000.0897000.0897000.0896000.0896000.0893000.0892000.0891000.0891000.0891000.0890000.0886000.0882000.0880000.0880000.0879000.0875000.0878000.0878000.0878000.0878000.0871000.0871000.0869000.0796000.0789000.0
Percentage of CommonStockValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Additional Paid In Capital

us-gaap:AdditionalPaidInCapital

us-gaap:AdditionalPaidInCapital


Additional
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value25292528252825312533253325352538253925532561256325642567256525662566257025762574257325712570256525622561256025562554254625392536253525332530253825382537253625212518251422922275
Percentage of AdditionalPaidInCapital100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets55.149.049.148.847.347.947.944.447.748.450.650.852.853.351.751.450.652.360.058.161.160.863.364.161.761.061.158.758.758.556.255.054.755.255.959.559.459.059.058.558.258.152.648.2

Retained Earnings Accumulated Deficit

us-gaap:RetainedEarningsAccumulatedDeficit

us-gaap:RetainedEarningsAccumulatedDeficit


Retained
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value-1194700000.0-1122700000.0-1130300000.0-1195900000.0-1135600000.0-1100700000.0-1042600000.0-969860000.0-895820000.0-855660000.0-1084500000.0-1110300000.0-1090700000.0-1071400000.0-1096400000.0-1081000000.0-1101100000.0-1045800000.0-1052200000.0-1053900000.0-1031900000.0-1066900000.0-1115600000.0-1070500000.0-930170000.0-952180000.0-936290000.0-913390000.0-902040000.0-939840000.0-897850000.0-817390000.0-795700000.0-792450000.0-764520000.0-715900000.0-690660000.0-661250000.0-647500000.0-624110000.0-605400000.0-583560000.0-560160000.0-470050000.0
Percentage of RetainedEarningsAccumulatedDeficit100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets-26.0-21.8-22.0-23.0-21.2-20.8-19.7-17.0-16.8-16.2-21.4-22.0-22.5-22.2-22.1-21.6-21.7-21.3-24.5-23.8-24.5-25.2-27.5-26.7-22.4-22.7-22.3-21.0-20.7-21.6-19.9-17.7-17.2-17.3-16.9-16.8-16.2-15.4-15.1-14.5-14.0-13.5-12.8-10.0

Minority Interest

us-gaap:MinorityInterest

us-gaap:MinorityInterest


Minority
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value175182193187194198205221230239210209190192192191189196199198200233228235255254257259262263276290294295301254258262264280283288285311
Percentage of MinorityInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets3.83.53.83.63.63.73.93.94.34.54.24.23.94.03.93.83.74.04.64.54.85.55.65.96.26.16.16.06.06.16.16.36.36.46.76.06.06.16.26.56.66.76.56.6

us-gaap:MinorityInterest us-gaap:StatementEquityComponents

us-gaap:NoncontrollingInterest


Minority
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302013-12-31
Value175182193187194198205221230239210209190192192191189196199198200233228235255254257259262276
Percentage of MinorityInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets3.83.53.83.63.63.73.93.94.34.54.24.23.94.03.93.83.74.04.64.54.85.55.65.96.26.16.16.06.06.1
Percentage of Assets us-gaap:NoncontrollingInterest0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Minority Interest Decrease From Distributions To Noncontrolling Interest Holders

us-gaap:MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders

us-gaap:MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders


Minority
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value0.02.029-0.792.272.2882.362.3611.6962.2622.3642.1362.262.3342.3342.3141.6471.6721.6731.6731.6011.5781.6191.6521.6561.6631.6641.6743.4553.5593.5963.6015.4375.4645.485.485.4845.48928-5.763-5.795
Percentage of MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders0.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders dei:LegalEntity

cli:MackCaliRealtyLp


Minority
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-31
Value0.020-0.792020202019202020202020201515
Percentage of MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders0.0994.1100.0898.2891.9867.2867.11165.2898.6863.8945.2897.7870.5870.5877.1918.5904.7
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of Assets cli:MackCaliRealtyLp0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders dei:LegalEntity, us-gaap:PartnerTypeOfPartnersCapitalAccount

cli:MackCaliRealtyLp, cli:GeneralPartnerCommonUnitholders


Minority
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value0.0180.01818181818181818
Percentage of MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders0.0894.1-0.0798.2791.9767.2767.11065.2798.6763.8845.2
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.0
Percentage of Assets cli:MackCaliRealtyLp cli:GeneralPartnerCommonUnitholders0.00.00.00.00.00.00.00.00.00.00.0

cli:MackCaliRealtyLp, cli:LimitedPartnersCommonUnitholders


Minority
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value0.02.029-0.792.272.2882.362.3611.6962.2622.3642.136
Percentage of MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders0.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.0
Percentage of Assets cli:MackCaliRealtyLp cli:LimitedPartnersCommonUnitholders0.00.00.00.00.00.00.00.00.00.00.0

us-gaap:MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders us-gaap:PartnerTypeOfPartnersCapitalAccount

cli:GeneralPartnerCommonUnitholders


Minority
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value180.018181818181818
Percentage of MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders894.1-0.0798.2767.2767.11065.2763.8845.2797.7
Percentage of Assets0.00.00.00.00.00.00.00.00.0
Percentage of Assets cli:GeneralPartnerCommonUnitholders0.00.00.00.00.00.00.00.00.0

us-gaap:MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders us-gaap:StatementEquityComponents

us-gaap:NoncontrollingInterest


Minority
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value0.02.029-0.792.272.2882.362.3611.6962.2622.3642.1362.262.3342.3342.3141.6471.6721.6731.6731.6011.5781.6191.6521.6561.6631.6641.6743.4553.5593.5963.6015.4375.4645.485.485.4845.48928-5.763-5.795
Percentage of MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders0.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of Assets us-gaap:NoncontrollingInterest0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Net Cash Provided By Used In Operating Activities

us-gaap:NetCashProvidedByUsedInOperatingActivities

us-gaap:NetCashProvidedByUsedInOperatingActivities


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value1.793268.8348.33424431052224640442556335852514330572755385549713679568146873679237941
Percentage of NetCashProvidedByUsedInOperatingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues2.234.411.510.733.853.212.639.517.534.330.733.519.840.923.436.832.234.20.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:NetCashProvidedByUsedInOperatingActivities dei:LegalEntity

cli:MackCaliRealtyLp


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value1.793268.8348.3342443105222464044255633585251
Percentage of NetCashProvidedByUsedInOperatingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues2.234.411.510.733.853.212.639.517.534.330.733.519.840.923.436.832.234.2
Percentage of Revenues cli:MackCaliRealtyLp2.234.411.510.733.853.212.639.517.534.330.733.519.840.923.436.832.234.2

Net Cash Provided By Used In Investing Activities

us-gaap:NetCashProvidedByUsedInInvestingActivities

us-gaap:NetCashProvidedByUsedInInvestingActivities


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value300189111111-111.082-83.098120-512.759-52.2128-0.636-215.404-95.662143-22.68127-227.953-422.53-15.5756920-24.216-101.78112675-128.778-130.43-28.544-20.315-53.067-27.572-21.004-26.82-18.781-42.747-15.352-17.498-13.428
Percentage of NetCashProvidedByUsedInInvestingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues369.4249.7145.5143.2-152.9-101.3138.5-388.8-40.021.5-0.5-163.0-75.6103.3-15.879.7-140.0-281.90.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:NetCashProvidedByUsedInInvestingActivities dei:LegalEntity

cli:MackCaliRealtyLp


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value300189111111-111.082-83.098120-512.759-52.2128-0.636-215.404-95.662143-22.68127-227.953-422.53
Percentage of NetCashProvidedByUsedInInvestingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues369.4249.7145.5143.2-152.9-101.3138.5-388.8-40.021.5-0.5-163.0-75.6103.3-15.879.7-140.0-281.9
Percentage of Revenues cli:MackCaliRealtyLp369.4249.7145.5143.2-152.9-101.3138.5-388.8-40.021.5-0.5-163.0-75.6103.3-15.879.7-140.0-281.9

Net Cash Provided By Used In Financing Activities

us-gaap:NetCashProvidedByUsedInFinancingActivities

us-gaap:NetCashProvidedByUsedInFinancingActivities


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-528.66512-105.336-122.6128539-144.17843675-91.857-21.56815062-208.282-57.978-134.93127511-104.158-75.232-56.117-166.226-40.321-34.928234595-5.727-60.564-3.811-49.242-28.081-53.308-28.612-120.296-43.218-195.1-44.605
Percentage of NetCashProvidedByUsedInFinancingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues-650.715.9-137.6-157.9118.148.0-166.3331.057.7-68.4-16.2113.749.2-149.9-40.4-84.316.9341.30.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:NetCashProvidedByUsedInFinancingActivities dei:LegalEntity

cli:MackCaliRealtyLp


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value-528.66512-105.336-122.6128539-144.17843675-91.857-21.56815062-208.282-57.978-134.93127511
Percentage of NetCashProvidedByUsedInFinancingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues-650.715.9-137.6-157.9118.148.0-166.3331.057.7-68.4-16.2113.749.2-149.9-40.4-84.316.9341.3
Percentage of Revenues cli:MackCaliRealtyLp-650.715.9-137.6-157.9118.148.0-166.3331.057.7-68.4-16.2113.749.2-149.9-40.4-84.316.9341.3

Amortization Of Financing Costs

us-gaap:AmortizationOfFinancingCosts

us-gaap:AmortizationOfFinancingCosts


Amortization
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value1467000.01074000.01060000.01024000.01147000.01121000.01168000.01189000.01485000.01302000.01145000.01096000.01150000.01184000.01175000.01103000.0999000.01234000.01180000.01169000.0944000.0945000.0948000.0953000.0968000.0778000.0759000.0769000.0793000.0954000.0809000.0773000.0724000.0673000.0661000.0611000.0618000.0584000.0584000.0584000.0635000.0646000.0660000.0
Percentage of AmortizationOfFinancingCosts100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Depreciation Depletion And Amortization

us-gaap:DepreciationDepletionAndAmortization

us-gaap:DepreciationDepletionAndAmortization


Depreciation
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value282728302632-16.015484847454540394550564651474343434442414142444548404746454748474848484847474748
Percentage of DepreciationDepletionAndAmortization100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DepreciationDepletionAndAmortization dei:LegalEntity

cli:MackCaliRealtyLp


Depreciation
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-31
Value282728302632-16.01548484745454039455056465147434343
Percentage of DepreciationDepletionAndAmortization100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Net Cash Provided By Used In Operating Activities

us-gaap:NetCashProvidedByUsedInOperatingActivities

us-gaap:NetCashProvidedByUsedInOperatingActivities


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value1.793268.8348.33424431052224640442556335852514330572755385549713679568146873679237941
Percentage of NetCashProvidedByUsedInOperatingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues2.234.411.510.733.853.212.639.517.534.330.733.519.840.923.436.832.234.20.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:NetCashProvidedByUsedInOperatingActivities dei:LegalEntity

cli:MackCaliRealtyLp


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value1.793268.8348.3342443105222464044255633585251
Percentage of NetCashProvidedByUsedInOperatingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues2.234.411.510.733.853.212.639.517.534.330.733.519.840.923.436.832.234.2
Percentage of Revenues cli:MackCaliRealtyLp2.234.411.510.733.853.212.639.517.534.330.733.519.840.923.436.832.234.2

Net Income Loss

us-gaap:NetIncomeLoss

us-gaap:NetIncomeLoss


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-72.0797.62365-42.208-34.887-39.924-54.652-55.928-22.05424443-1.478-1.251432.58238-37.331915-8.5414862-31.718-126.89235-2.521-9.241.98251-15.298-54.1794.6432311-9.227141025162017156.627131814
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues-88.710.085.7-54.4-48.0-48.7-63.1-42.4-16.9182.133.0-1.1-1.031.01.823.8-22.913.30.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:NetIncomeLoss dei:LegalEntity

cli:MackCaliRealtyLp


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value-79.3048.38572-46.694-38.576-44.139-60.475-62.087-24.48827248-1.645-1.393472.88142-41.6262216-9.545469-35.513-142.42239-2.835
Percentage of NetIncomeLoss110.0110.0110.7110.6110.6110.6110.7111.0111.0111.3111.3111.3111.4111.3111.6111.6111.5111.5111.7111.7111.7111.7112.0112.2112.4112.5
Percentage of Revenues-97.611.094.9-60.1-53.1-53.8-69.8-47.1-18.8202.736.7-1.2-1.134.52.026.5-25.614.80.00.00.00.00.00.00.00.0
Percentage of Revenues cli:MackCaliRealtyLp-97.611.094.9-60.1-53.1-53.8-69.8-47.1-18.8202.736.7-1.2-1.134.52.026.5-25.614.80.00.00.00.00.00.00.00.0

Profit Loss

us-gaap:ProfitLoss

us-gaap:ProfitLoss


Profit
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-74.0311378-41.118-32.934-37.844-55.408-56.021-20.329275521.6891.501505.41144-39.1252216-9.6055468-35.975-142.14139-3.325-10.4132.08557-17.628-61.773.4392613-10.585161129182420188.232152217
Percentage of ProfitLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues-91.117.8102.3-53.0-45.3-46.1-63.9-42.5-15.6205.339.51.31.236.53.827.9-24.015.20.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:ProfitLoss dei:LegalEntity

cli:MackCaliRealtyLp


Profit
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value-74.0311378-41.118-32.934-37.844-55.408-56.021-20.329275521.6891.501505.41144-39.1252216-9.6055468-35.975-142.14139-3.325
Percentage of ProfitLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues-91.117.8102.3-53.0-45.3-46.1-63.9-42.5-15.6205.339.51.31.236.53.827.9-24.015.20.00.00.00.00.00.00.00.0
Percentage of Revenues cli:MackCaliRealtyLp-91.117.8102.3-53.0-45.3-46.1-63.9-42.5-15.6205.339.51.31.236.53.827.9-24.015.20.00.00.00.00.00.00.00.0

Share Based Compensation

us-gaap:ShareBasedCompensation

us-gaap:ShareBasedCompensation


Share
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value2.5432.5291.9430.7232.4392.532.111.982.1911.881.9351.770.6572.5322.1692.0461.0532.0461.4680.7850.7190.6950.4920.3134.6580.8761.024.543-0.0640.7641.0810.6061.7970.7030.7010.9342.1640.7990.7970.7972.3550.7290.7280.716
Percentage of ShareBasedCompensation100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ShareBasedCompensation dei:LegalEntity

cli:MackCaliRealtyLp


Share
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-31
Value2.5432.5291.9430.7232.4392.532.111.982.1911.881.9351.770.6572.5322.1692.0461.0532.0461.4680.785
Percentage of ShareBasedCompensation100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Net Cash Provided By Used In Investing Activities

us-gaap:NetCashProvidedByUsedInInvestingActivities

us-gaap:NetCashProvidedByUsedInInvestingActivities


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value300189111111-111.082-83.098120-512.759-52.2128-0.636-215.404-95.662143-22.68127-227.953-422.53-15.5756920-24.216-101.78112675-128.778-130.43-28.544-20.315-53.067-27.572-21.004-26.82-18.781-42.747-15.352-17.498-13.428
Percentage of NetCashProvidedByUsedInInvestingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues369.4249.7145.5143.2-152.9-101.3138.5-388.8-40.021.5-0.5-163.0-75.6103.3-15.879.7-140.0-281.90.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:NetCashProvidedByUsedInInvestingActivities dei:LegalEntity

cli:MackCaliRealtyLp


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value300189111111-111.082-83.098120-512.759-52.2128-0.636-215.404-95.662143-22.68127-227.953-422.53
Percentage of NetCashProvidedByUsedInInvestingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues369.4249.7145.5143.2-152.9-101.3138.5-388.8-40.021.5-0.5-163.0-75.6103.3-15.879.7-140.0-281.9
Percentage of Revenues cli:MackCaliRealtyLp369.4249.7145.5143.2-152.9-101.3138.5-388.8-40.021.5-0.5-163.0-75.6103.3-15.879.7-140.0-281.9

Net Cash Provided By Used In Financing Activities

us-gaap:NetCashProvidedByUsedInFinancingActivities

us-gaap:NetCashProvidedByUsedInFinancingActivities


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-528.66512-105.336-122.6128539-144.17843675-91.857-21.56815062-208.282-57.978-134.93127511-104.158-75.232-56.117-166.226-40.321-34.928234595-5.727-60.564-3.811-49.242-28.081-53.308-28.612-120.296-43.218-195.1-44.605
Percentage of NetCashProvidedByUsedInFinancingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues-650.715.9-137.6-157.9118.148.0-166.3331.057.7-68.4-16.2113.749.2-149.9-40.4-84.316.9341.30.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:NetCashProvidedByUsedInFinancingActivities dei:LegalEntity

cli:MackCaliRealtyLp


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value-528.66512-105.336-122.6128539-144.17843675-91.857-21.56815062-208.282-57.978-134.93127511
Percentage of NetCashProvidedByUsedInFinancingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues-650.715.9-137.6-157.9118.148.0-166.3331.057.7-68.4-16.2113.749.2-149.9-40.4-84.316.9341.3
Percentage of Revenues cli:MackCaliRealtyLp-650.715.9-137.6-157.9118.148.0-166.3331.057.7-68.4-16.2113.749.2-149.9-40.4-84.316.9341.3

Repayments Of Long Term Debt

us-gaap:RepaymentsOfLongTermDebt us-gaap:DebtInstrument, us-gaap:DisposalGroupClassification, us-gaap:SubsequentEventType

us-gaap:RepaymentsOfLongTermDebt

cli:ShortHillsPortfolio, us-gaap:DisposalGroupHeldforsaleNotDiscontinuedOperations, us-gaap:SubsequentEvent


Repayments
Period End2021-04-30
Value22
Percentage of RepaymentsOfLongTermDebt100.0

us-gaap:RepaymentsOfLongTermDebt us-gaap:DisposalGroupClassification, us-gaap:SubsequentEventType

us-gaap:DisposalGroupHeldforsaleNotDiscontinuedOperations, us-gaap:SubsequentEvent


Repayments
Period End2021-04-30
Value124
Percentage of RepaymentsOfLongTermDebt565.9

us-gaap:RepaymentsOfLongTermDebt us-gaap:StatementGeographical, us-gaap:DisposalGroupClassification, us-gaap:SubsequentEventType

cli:ShortHillsNewJersey, us-gaap:DisposalGroupHeldforsaleNotDiscontinuedOperations, us-gaap:SubsequentEvent


Repayments
Period End2021-04-30
Value22
Percentage of RepaymentsOfLongTermDebt100.0

Payments For Repurchase Of Common Stock

us-gaap:PaymentsForRepurchaseOfCommonStock

us-gaap:PaymentsForRepurchaseOfCommonStock


Payments
Period End2020-12-312020-09-302020-06-302020-03-31
Value523000.029000.002141000.0
Percentage of PaymentsForRepurchaseOfCommonStock100.0100.00.0100.0

us-gaap:PaymentsForRepurchaseOfCommonStock dei:LegalEntity

cli:MackCaliRealtyLp


Payments
Period End2020-12-312020-09-302020-06-302020-03-31
Value523000.029000.002141000.0
Percentage of PaymentsForRepurchaseOfCommonStock100.0100.00.0100.0

Deferred Tax Assets Valuation Allowance

us-gaap:DeferredTaxAssetsValuationAllowance

us-gaap:DeferredTaxAssetsValuationAllowance


Deferred
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312014-12-312013-12-31
Value161812109.89.51111109.8109.75.31413
Percentage of DeferredTaxAssetsValuationAllowance100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DeferredTaxAssetsValuationAllowance us-gaap:DisposalGroupClassification, us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations

us-gaap:DisposalGroupNotDiscontinuedOperations, cli:FiveHundredCollegeRoadEast


Deferred
Period End2020-12-31
Value1.9
Percentage of DeferredTaxAssetsValuationAllowance11.7

us-gaap:DisposalGroupNotDiscontinuedOperations, cli:MorrisPortfolio


Deferred
Period End2020-12-312020-09-302019-12-31
Value212132
Percentage of DeferredTaxAssetsValuationAllowance133.3116.8331.6

us-gaap:DisposalGroupNotDiscontinuedOperations, cli:ThreeGiraldaFarms


Deferred
Period End2020-12-312020-09-302019-12-31
Value2.02.016
Percentage of DeferredTaxAssetsValuationAllowance12.310.8170.4

cli:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationValue

cli:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationValue


Adjustments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value2543000.02529000.01943000.0723000.02439000.02530000.02110000.01980000.02191000.01880000.01935000.01770000.0657000.02532000.02179000.02169000.0
Percentage of AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationValue dei:LegalEntity

cli:MackCaliRealtyLp


Adjustments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value2543000.02529000.01943000.0723000.02439000.02530000.02110000.01980000.02191000.01880000.01935000.01770000.0657000.02532000.02179000.02169000.0
Percentage of AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationValue dei:LegalEntity, us-gaap:PartnerTypeOfPartnersCapitalAccount

cli:MackCaliRealtyLp, cli:GeneralPartnerCommonUnitholders


Adjustments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value1239000.0646000.0456000.0394000.0334000.0430000.0137000.07000.0218000.0265000.0261000.0202000.0434000.0
Percentage of AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationValue48.725.523.554.513.717.06.50.49.914.113.511.466.1

cli:MackCaliRealtyLp, cli:LimitedPartnersCommonUnitholders


Adjustments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value1304000.01883000.01487000.0329000.02105000.02100000.01973000.01973000.01973000.01615000.01674000.01568000.0223000.0
Percentage of AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationValue51.374.576.545.586.383.093.599.690.185.986.588.633.9

cli:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationValue us-gaap:StatementEquityComponents

us-gaap:AdditionalPaidInCapital


Adjustments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value1239000.0646000.0456000.0394000.0334000.0430000.0137000.07000.0218000.0265000.0261000.0202000.0433000.0517000.0849000.0840000.0
Percentage of AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationValue48.725.523.554.513.717.06.50.49.914.113.511.465.920.439.038.7

us-gaap:NoncontrollingInterest


Adjustments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value1304000.01883000.01487000.0329000.02105000.02100000.01973000.01973000.01973000.01615000.01674000.01568000.0223000.02015000.01330000.01329000.0
Percentage of AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationValue51.374.576.545.586.383.093.599.690.185.986.588.633.979.661.061.3

cli:AmortizationOfDebtDiscountAndMarkToMarket

cli:AmortizationOfDebtDiscountAndMarkToMarket


Amortization
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-31
Value65000.0167000.0-372000.0-237000.0-237000.0-237000.0-238000.0-237000.0-237000.0-237000.0-237000.0-237000.0-237000.0-237000.0-201000.0-164000.0-163000.0241000.0269000.0
Percentage of AmortizationOfDebtDiscountAndMarkToMarket100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:AmortizationOfDebtDiscountAndMarkToMarket dei:LegalEntity

cli:MackCaliRealtyLp


Amortization
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-31
Value65000.0167000.0-372000.0-237000.0-237000.0-237000.0-238000.0-237000.0-237000.0-237000.0-237000.0-237000.0-237000.0-237000.0-201000.0-164000.0-163000.0241000.0269000.0
Percentage of AmortizationOfDebtDiscountAndMarkToMarket100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:AmortizationOfDeferredStockUnits

cli:AmortizationOfDeferredStockUnits


Amortization
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value66000.072000.076000.076000.057000.082000.081000.081000.027000.0130000.0129000.0127000.0126000.0125000.0124000.0122000.0121000.0115000.087000.087000.097000.0101000.0100000.0100000.099000.098000.098000.096000.096000.0117000.0
Percentage of AmortizationOfDeferredStockUnits100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:AmortizationOfDeferredStockUnits dei:LegalEntity

cli:MackCaliRealtyLp


Amortization
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-31
Value66000.072000.076000.076000.057000.082000.081000.081000.027000.0130000.0129000.0127000.0126000.0125000.0124000.0122000.0121000.0115000.087000.087000.097000.0101000.0100000.0
Percentage of AmortizationOfDeferredStockUnits100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:AnnualBaseSalary us-gaap:TitleOfIndividual

cli:AnnualBaseSalary

cli:AnnaMalhariEvpAndCoo


Annual
Period End2021-06-09
Value300000.0
Percentage of AnnualBaseSalary100.0

cli:DavidSmetana


Annual
Period End2020-11-03
Value450000.0
Percentage of AnnualBaseSalary0.0

cli:GaryT.Wagner


Annual
Period End2020-11-03
Value450000.0
Percentage of AnnualBaseSalary0.0

cli:MahbodNiaChiefExecutiveOfficer


Annual
Period End2021-03-08
Value800000.0
Percentage of AnnualBaseSalary0.0

cli:RicardoCardoso


Annual
Period End2020-11-03
Value550000.0
Percentage of AnnualBaseSalary0.0

cli:AnnualBaseSalaryForTargetPerformancePercentag us-gaap:TitleOfIndividual

cli:AnnualBaseSalaryForTargetPerformancePercentag

cli:DavidSmetana


Annual
Period End2020-11-03
Value100.0
Percentage of AnnualBaseSalaryForTargetPerformancePercentag100.0

cli:GaryT.Wagner


Annual
Period End2020-11-03
Value100.0
Percentage of AnnualBaseSalaryForTargetPerformancePercentag100.0

cli:MessieurDebari


Annual
Period End2020-11-03
Value40.0
Percentage of AnnualBaseSalaryForTargetPerformancePercentag40.0

cli:RicardoCardoso


Annual
Period End2020-11-03
Value100.0
Percentage of AnnualBaseSalaryForTargetPerformancePercentag100.0

cli:AnnualBonusOpportunityPercentage us-gaap:Range, us-gaap:TitleOfIndividual

cli:AnnualBonusOpportunityPercentage

srt:Maximum, cli:DavidSmetana


Annual
Period End2020-11-03
Value150.0
Percentage of AnnualBonusOpportunityPercentage100.0

srt:Maximum, cli:MessieurDebari


Annual
Period End2020-11-03
Value60.0
Percentage of AnnualBonusOpportunityPercentage40.0

srt:Maximum, cli:RicardoCardoso


Annual
Period End2020-11-03
Value200.0
Percentage of AnnualBonusOpportunityPercentage133.3

cli:AnnualBonusOpportunityPercentage us-gaap:TitleOfIndividual

cli:AnnaMalhariEvpAndCoo


Annual
Period End2021-06-09
Value100.0
Percentage of AnnualBonusOpportunityPercentage0.0

cli:MahbodNiaChiefExecutiveOfficer


Annual
Period End2021-03-08
Value150.0
Percentage of AnnualBonusOpportunityPercentage0.0

cli:MichaelJ.DemarcoChiefExecutiveOfficer


Annual
Period End2020-12-312019-12-312019-09-302019-06-302019-03-31
Value00001.5
Percentage of AnnualBonusOpportunityPercentage0.00.00.00.00.0

cli:AnnualBonusOpportunityThresholdPercentage us-gaap:Range

cli:AnnualBonusOpportunityThresholdPercentage

srt:Maximum


Annual
Period End2021-03-08
Value200.0
Percentage of AnnualBonusOpportunityThresholdPercentage100.0

cli:AnnualBonusOpportunityThresholdPercentage us-gaap:Range, us-gaap:TitleOfIndividual

srt:Maximum, cli:GaryT.Wagner


Annual
Period End2020-11-03
Value150.0
Percentage of AnnualBonusOpportunityThresholdPercentage0.0

cli:AnnualBonusOpportunityThresholdPercentage us-gaap:TitleOfIndividual

cli:AnnaMalhariEvpAndCoo


Annual
Period End2021-06-09
Value50.0
Percentage of AnnualBonusOpportunityThresholdPercentage0.0

cli:DavidSmetana


Annual
Period End2020-11-03
Value50.0
Percentage of AnnualBonusOpportunityThresholdPercentage0.0

cli:GaryT.Wagner


Annual
Period End2020-11-03
Value50.0
Percentage of AnnualBonusOpportunityThresholdPercentage0.0

cli:MahbodNiaChiefExecutiveOfficer


Annual
Period End2021-03-08
Value50.0
Percentage of AnnualBonusOpportunityThresholdPercentage25.0

cli:MessieurDebari


Annual
Period End2020-11-03
Value20.0
Percentage of AnnualBonusOpportunityThresholdPercentage0.0

cli:RicardoCardoso


Annual
Period End2020-11-03
Value50.0
Percentage of AnnualBonusOpportunityThresholdPercentage0.0

cli:AnnualHealthCoverage us-gaap:Range, us-gaap:TitleOfIndividual

cli:AnnualHealthCoverage

srt:Maximum, cli:MahbodNiaChiefExecutiveOfficer


Annual
Period End2021-03-10
Value25000.0
Percentage of AnnualHealthCoverage100.0

cli:AnnualMaximumBonusPercentage us-gaap:TitleOfIndividual

cli:AnnualMaximumBonusPercentage

cli:AnnaMalhariEvpAndCoo


Annual
Period End2021-06-09
Value150.0
Percentage of AnnualMaximumBonusPercentage100.0

cli:AnnualPercentageOfCostForPhaseIn us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty, us-gaap:TaxPeriod

cli:AnnualPercentageOfCostForPhaseIn

cli:PortImperialSouthOneThirdGarageDevelopment, cli:TaxYearFive


Annual
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value095.0094.0500.950000.950000.950000.9500
Percentage of AnnualPercentageOfCostForPhaseIn0.0100.00.0100.00.0100.00.00.00.0100.00.00.00.0100.00.00.00.0100.00.00.0

cli:PortImperialSouthOneThirdGarageDevelopment, cli:TaxYearFour


Annual
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value095.0094.0500.950000.950000.950000.9500
Percentage of AnnualPercentageOfCostForPhaseIn0.0100.00.0100.00.0100.00.00.00.0100.00.00.00.0100.00.00.00.0100.00.00.0

cli:PortImperialSouthOneThirdGarageDevelopment, cli:TaxYearThree


Annual
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value095.0094.0500.950000.950000.950000.9500
Percentage of AnnualPercentageOfCostForPhaseIn0.0100.00.0100.00.0100.00.00.00.0100.00.00.00.0100.00.00.00.0100.00.00.0

cli:PortImperialSouthOneThirdGarageDevelopment, cli:TaxYearTwo


Annual
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value095.0094.0500.950000.950000.950000.9500
Percentage of AnnualPercentageOfCostForPhaseIn0.0100.00.0100.00.0100.00.00.00.0100.00.00.00.0100.00.00.00.0100.00.00.0

cli:AnnualReturnFromCashFlowOperations us-gaap:ConsolidatedEntities, us-gaap:StatementScenario, us-gaap:RelatedPartyTransactionsByRelatedParty

cli:AnnualReturnFromCashFlowOperations

cli:RockpointGroupL.l.c., cli:CashFlowFromOperations, cli:RoselandResidentialL.p.


Annual
Period End2021-06-302021-03-31
Value06.0
Percentage of AnnualReturnFromCashFlowOperations0.0100.0

cli:AnnualReturnOnEquityValue us-gaap:StatementScenario, us-gaap:RelatedPartyTransactionsByRelatedParty

cli:AnnualReturnOnEquityValue

cli:CashFlowFromOperations, cli:RoselandResidentialL.p.


Annual
Period End2021-06-302021-03-312020-12-31
Value06.00
Percentage of AnnualReturnOnEquityValue0.0100.00.0

cli:AnnualReturnOnEquityValueBaseReturn us-gaap:ConsolidatedEntities, us-gaap:StatementScenario, us-gaap:RelatedPartyTransaction, us-gaap:RelatedPartyTransactionsByRelatedParty

cli:AnnualReturnOnEquityValueBaseReturn

cli:RockpointGroupL.l.c., cli:CashFlowFromCapitalEventsDistributionThree, cli:InvestmentAgreement, cli:RoselandResidentialL.p.


Annual
Period End2021-06-302021-03-312020-09-302020-06-302020-03-31
Value095.094.0500.95
Percentage of AnnualReturnOnEquityValueBaseReturn0.0100.0100.00.0100.0

cli:RockpointGroupL.l.c., cli:CashFlowFromOperations, cli:InvestmentAgreement, cli:RoselandResidentialL.p.


Annual
Period End2021-06-302021-03-312020-09-302020-06-302020-03-31
Value05.04.9500.05
Percentage of AnnualReturnOnEquityValueBaseReturn0.05.35.30.05.3

cli:RoselandResidentialTrust, cli:CashFlowFromCapitalEventsDistributionThree, cli:InvestmentAgreement, cli:RoselandResidentialL.p.


Annual
Period End2021-06-302021-03-312020-09-302020-06-302020-03-31
Value05.04.9500.05
Percentage of AnnualReturnOnEquityValueBaseReturn0.05.35.30.05.3

cli:RoselandResidentialTrust, cli:CashFlowFromOperations, cli:InvestmentAgreement, cli:RoselandResidentialL.p.


Annual
Period End2021-06-302021-03-312020-09-302020-06-302020-03-31
Value095.094.0500.95
Percentage of AnnualReturnOnEquityValueBaseReturn0.0100.0100.00.0100.0

cli:AnnualReturnOnEquityValueBaseReturn us-gaap:ConsolidatedEntities, us-gaap:StatementScenario, us-gaap:RelatedPartyTransactionsByRelatedParty

cli:RockpointGroupL.l.c., cli:CashFlowFromCapitalEventsDistributionThree, cli:RoselandResidentialL.p.


Annual
Period End2021-06-302021-03-312020-09-302020-06-302020-03-31
Value04.644.593600.0464
Percentage of AnnualReturnOnEquityValueBaseReturn0.04.94.90.04.9

cli:RockpointGroupL.l.c., cli:CashFlowFromOperations, cli:RoselandResidentialL.p.


Annual
Period End2021-06-302021-03-312020-09-302020-06-302020-03-31
Value04.644.593600.0464
Percentage of AnnualReturnOnEquityValueBaseReturn0.04.94.90.04.9

cli:RoselandResidentialTrust, cli:CashFlowFromCapitalEventsDistributionThree, cli:RoselandResidentialL.p.


Annual
Period End2021-06-302021-03-312020-09-302020-06-302020-03-31
Value095.3694.40600.9536
Percentage of AnnualReturnOnEquityValueBaseReturn0.0100.4100.40.0100.4

cli:RoselandResidentialTrust, cli:CashFlowFromOperations, cli:RoselandResidentialL.p.


Annual
Period End2021-06-302021-03-312020-09-302020-06-302020-03-31
Value095.3694.40600.9536
Percentage of AnnualReturnOnEquityValueBaseReturn0.0100.4100.40.0100.4

cli:AnnualReturnOnEquityValueCapitalBaseReturn us-gaap:ConsolidatedEntities, us-gaap:StatementScenario, us-gaap:RelatedPartyTransaction, us-gaap:RelatedPartyTransactionsByRelatedParty

cli:AnnualReturnOnEquityValueCapitalBaseReturn

cli:RoselandResidentialTrust, cli:CashFlowFromCapitalEventsDistributionFour, cli:InvestmentAgreement, cli:RoselandResidentialL.p.


Annual
Period End2021-06-302021-03-312020-09-302020-06-302020-03-31
Value095.094.0500.95
Percentage of AnnualReturnOnEquityValueCapitalBaseReturn0.0100.0100.00.0100.0

cli:AnnualReturnOnEquityValueCapitalBaseReturn us-gaap:ConsolidatedEntities, us-gaap:StatementScenario, us-gaap:RelatedPartyTransactionsByRelatedParty

cli:RockpointGroupL.l.c., cli:CashFlowFromCapitalEventsDistributionFour, cli:RoselandResidentialL.p.


Annual
Period End2021-06-302021-03-312020-09-302020-06-302020-03-31
Value04.644.593600.0464
Percentage of AnnualReturnOnEquityValueCapitalBaseReturn0.04.94.90.04.9

cli:RoselandResidentialTrust, cli:CashFlowFromCapitalEventsDistributionFour, cli:RoselandResidentialL.p.


Annual
Period End2021-06-302021-03-312020-09-302020-06-302020-03-31
Value095.3694.40600.9536
Percentage of AnnualReturnOnEquityValueCapitalBaseReturn0.0100.4100.40.0100.4

cli:AnnualReturnOnEquityValueCapitalBaseReturn us-gaap:StatementScenario, us-gaap:RelatedPartyTransaction, us-gaap:RelatedPartyTransactionsByRelatedParty

cli:CashFlowFromCapitalEventsDistributionFour, cli:InvestmentAgreement, cli:RoselandResidentialL.p.


Annual
Period End2021-06-302021-03-312020-09-302020-06-302020-03-31
Value05.04.9500.05
Percentage of AnnualReturnOnEquityValueCapitalBaseReturn0.05.35.30.05.3

cli:AnnualTaxComplianceAssistance us-gaap:Range, us-gaap:TitleOfIndividual

cli:AnnualTaxComplianceAssistance

srt:Maximum, cli:MahbodNiaChiefExecutiveOfficer


Annual
Period End2021-03-10
Value30000.0
Percentage of AnnualTaxComplianceAssistance100.0

cli:AreaOfMixedUseProperty us-gaap:MortgageLoansOnRealEstateDescriptionTypeOfProperty

cli:AreaOfMixedUseProperty

cli:UnconsolidatedJointVentureRetailBuildings


Area
Period End2021-06-302021-03-312020-12-31
Value051000.00
Percentage of AreaOfMixedUseProperty0.0100.00.0

cli:BuildingsAndImprovementsNetOfAccumulatedDepreciation

cli:BuildingsAndImprovementsNetOfAccumulatedDepreciation


Buildings
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value1.816012-2.4-16.5166-7.20.1-43.6207-15.8166.5197
Percentage of BuildingsAndImprovementsNetOfAccumulatedDepreciation100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:BuildingsAndImprovementsNetOfAccumulatedDepreciation us-gaap:DisposalGroupClassification

us-gaap:DisposalGroupHeldforsaleNotDiscontinuedOperations


Buildings
Period End2021-06-302021-03-312020-09-302020-06-302020-03-31
Value0.26.5-4.2-25.639
Percentage of BuildingsAndImprovementsNetOfAccumulatedDepreciation11.14.1175.0155.223.7

cli:BuildingsAndImprovementsNetOfAccumulatedDepreciation us-gaap:DisposalGroupClassification, us-gaap:PropertyPlantAndEquipmentByType

us-gaap:DisposalGroupHeldforsaleNotDiscontinuedOperations, cli:Development


Buildings
Period End2020-12-312020-09-302020-06-302020-03-31
Value7.90.3-4.95.6
Percentage of BuildingsAndImprovementsNetOfAccumulatedDepreciation62.7-12.529.73.4

cli:CapitalizedDevelopmentConstructionSalariesAndOtherRelatedExpenses

cli:CapitalizedDevelopmentConstructionSalariesAndOtherRelatedExpenses


Capitalized
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
Value600000.0600000.0700000.0400000.0400000.0500000.0500000.0500000.0600000.0600000.0600000.0600000.0600000.0600000.0400000.0600000.0600000.0600000.0700000.0700000.0800000.0600000.0700000.0900000.01200000.01300000.0400000.01000000.0900000.0900000.0700000.01900000.0900000.0900000.01062000.0765000.0770000.01000000.0851000.0969000.0909000.0
Percentage of CapitalizedDevelopmentConstructionSalariesAndOtherRelatedExpenses100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:CashDistributionPercent us-gaap:TitleOfIndividual, us-gaap:AwardType

cli:CashDistributionPercent

cli:MichaelJ.DemarcoChiefExecutiveOfficer, cli:AoLtipUnitsAward


Cash
Period End2021-06-302021-03-312020-12-31
Value010.00
Percentage of CashDistributionPercent0.0100.00.0

cli:CommonStockDividendsAndCommonUnitDistributionsPerShare us-gaap:SubsequentEventType

cli:CommonStockDividendsAndCommonUnitDistributionsPerShare

us-gaap:SubsequentEvent


Common
Period End2020-07-01
Value0.2
Percentage of CommonStockDividendsAndCommonUnitDistributionsPerShare100.0

cli:CommonUnits

cli:CommonUnits


Common
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value9.0999.0680.0169.6369.5849.567-0.1059.9769.9910-0.0051010100.011101010-0.003101010-0.076101111-0.062111111-0.031111212-0.004121212-0.056121212-0.0471313
Percentage of CommonUnits100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:ComprehensiveIncomeLossNetOfTaxAttributableToNoncontrollingInterestJointVenturePartnersNonredeemable

cli:ComprehensiveIncomeLossNetOfTaxAttributableToNoncontrollingInterestJointVenturePartnersNonredeemable


Comprehensive
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value-1198000.0-1335000.0-795000.0-895000.0-829000.0-176000.0-1404000.0-405000.0-847000.0-1248000.0-640000.0-451000.0-95000.0-30000.0-153000.0-447000.0-181000.0-237000.0-191000.0-65000.0311000.0-706000.0-462000.0281000.0-373000.0-490000.0
Percentage of ComprehensiveIncomeLossNetOfTaxAttributableToNoncontrollingInterestJointVenturePartnersNonredeemable100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:ComprehensiveIncomeLossNetOfTaxAttributableToNoncontrollingInterestJointVenturePartnersNonredeemable dei:LegalEntity

cli:MackCaliRealtyLp


Comprehensive
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-30
Value-1198000.0-1335000.0-795000.0-895000.0-829000.0-176000.0-1404000.0-405000.0-847000.0-1248000.0-640000.0-451000.0-95000.0-30000.0-153000.0-447000.0-181000.0-237000.0-191000.0-65000.0311000.0-706000.0-462000.0281000.0
Percentage of ComprehensiveIncomeLossNetOfTaxAttributableToNoncontrollingInterestJointVenturePartnersNonredeemable100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:ComprehensiveIncomeLossNetOfTaxAttributableToNoncontrollingInterestOperatingPartnershipsNonredeemable

cli:ComprehensiveIncomeLossNetOfTaxAttributableToNoncontrollingInterestOperatingPartnershipsNonredeemable


Comprehensive
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value-7.225-0.7626.991-4.486-3.689-4.249-5.843-6.246-2.894274.448-0.1310.045.4070.7824.489-4.4362.4222.794-0.8185.3577.284-3.795-15.534.383-0.314
Percentage of ComprehensiveIncomeLossNetOfTaxAttributableToNoncontrollingInterestOperatingPartnershipsNonredeemable100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:ComprehensiveIncomeLossNetOfTaxAttributableToRedeemableNoncontrollingInterest

cli:ComprehensiveIncomeLossNetOfTaxAttributableToRedeemableNoncontrollingInterest


Comprehensive
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value6.4716.4716.476.4716.4716.4716.4716.4715.0064.6674.4063.7852.9892.7992.6832.6832.6820.792
Percentage of ComprehensiveIncomeLossNetOfTaxAttributableToRedeemableNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:ComprehensiveIncomeLossNetOfTaxAttributableToRedeemableNoncontrollingInterest dei:LegalEntity

cli:MackCaliRealtyLp


Comprehensive
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value6.4716.4716.4716.4716.4716.4715.0064.6674.4063.7852.9892.7992.6832.6832.6820.792
Percentage of ComprehensiveIncomeLossNetOfTaxAttributableToRedeemableNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:ConstructionCostsIncurred us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty

cli:ConstructionCostsIncurred

cli:PortImperialSouthNine


Construction
Period End2021-06-302021-03-31
Value13112
Percentage of ConstructionCostsIncurred100.0100.0

cli:TwentyFiveChristopherColumbus


Construction
Period End2021-06-302021-03-31
Value30353
Percentage of ConstructionCostsIncurred220.3315.5

cli:CostsOfRealEstateServices

cli:CostsOfRealEstateServices


Costs
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value3.2133.3183.4493.33.0853.7213.7683.9053.9794.2664.2234.44.364.9365.0186.2075.8996.276.8426.3616.2116.8466.0636.6736.2086.6395.9236.9336.5716.7096.9075.5525.3044.9522.2040.5360.5010.504
Percentage of CostsOfRealEstateServices100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:CostsOfRealEstateServices dei:LegalEntity

cli:MackCaliRealtyLp


Costs
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-30
Value3.2133.3183.4493.33.0853.7213.7683.9053.9794.2664.2234.44.364.9365.0186.2075.8996.276.8426.3616.2116.8466.0636.673
Percentage of CostsOfRealEstateServices100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:DeadDealAndTransactionRelatedCosts

cli:DeadDealAndTransactionRelatedCosts


Dead
Period End2021-06-302020-06-30
Value2745000.0277000.0
Percentage of DeadDealAndTransactionRelatedCosts100.0100.0

cli:DeadDealAndTransactionRelatedCosts dei:LegalEntity

cli:MackCaliRealtyLp


Dead
Period End2021-06-302020-06-30
Value2745000.0277000.0
Percentage of DeadDealAndTransactionRelatedCosts100.0100.0

cli:DebtInstrumentClosingCostsToDefeaseLoan us-gaap:CreditFacility, us-gaap:DebtInstrument

cli:DebtInstrumentClosingCostsToDefeaseLoan

us-gaap:SecuredDebt, cli:RxrShortHills


Debt
Period End2021-04-30
Value22
Percentage of DebtInstrumentClosingCostsToDefeaseLoan100.0

cli:DebtInstrumentInitialTermCommitmentPercentageBorrowed us-gaap:DebtInstrument

cli:DebtInstrumentInitialTermCommitmentPercentageBorrowed

cli:TwentySeventeenTermLoan


Debt
Period End2021-03-312020-12-31
Value50.00
Percentage of DebtInstrumentInitialTermCommitmentPercentageBorrowed100.00.0

cli:DebtInstrumentMaximumCollateralPoolLeverageRatio us-gaap:Range, us-gaap:CreditFacility

cli:DebtInstrumentMaximumCollateralPoolLeverageRatio

srt:Maximum, cli:TwentyTwentyOneSeniorSecuredCreditFacility


Debt
Period End2021-05-06
Value40.0
Percentage of DebtInstrumentMaximumCollateralPoolLeverageRatio100.0

cli:DebtInstrumentMaximumCollateralPoolLeverageRatio us-gaap:Range, us-gaap:CreditFacility, us-gaap:SubsequentEventType

srt:Maximum, cli:TwentyTwentyOneSeniorSecuredCreditFacility, us-gaap:SubsequentEvent


Debt
Period End2021-05-06
Value40.0
Percentage of DebtInstrumentMaximumCollateralPoolLeverageRatio100.0

cli:DebtInstrumentTermCommitmentFeePerAnnum us-gaap:DebtInstrument

cli:DebtInstrumentTermCommitmentFeePerAnnum

cli:TwentySeventeenTermLoan


Debt
Period End2021-03-312020-12-31
Value0.250
Percentage of DebtInstrumentTermCommitmentFeePerAnnum100.00.0

cli:DebtInstrumentTotalLeverageRatio us-gaap:Range, us-gaap:CreditFacility

cli:DebtInstrumentTotalLeverageRatio

srt:Maximum, cli:TwentyTwentyOneSeniorSecuredCreditFacility


Debt
Period End2021-05-06
Value65.0
Percentage of DebtInstrumentTotalLeverageRatio100.0

cli:DebtInstrumentTotalLeverageRatio us-gaap:Range, us-gaap:CreditFacility, us-gaap:SubsequentEventType

srt:Maximum, cli:TwentyTwentyOneSeniorSecuredCreditFacility, us-gaap:SubsequentEvent


Debt
Period End2021-05-06
Value65.0
Percentage of DebtInstrumentTotalLeverageRatio100.0

cli:DepreciationAmortizationOnDiscontinuedOperations

cli:DepreciationAmortizationOnDiscontinuedOperations


Depreciation
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-06-302010-03-31
Value0.2530.6590.5351.3661.4531.453211617160.0221.7690.2340.2972.6490.0130.0130.4152.2590.4160.4220.4410.3020.107
Percentage of DepreciationAmortizationOnDiscontinuedOperations100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:DisposalGroupIncludingDiscontinuedOperationGainLossOnDispositionOfAssets

cli:DisposalGroupIncludingDiscontinuedOperationGainLossOnDispositionOfAssets


Disposal
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312013-12-312013-09-302013-06-302012-12-312012-09-30
Value3.0312115150.017-1.5594737-0.0860.012
Percentage of DisposalGroupIncludingDiscontinuedOperationGainLossOnDispositionOfAssets100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0

cli:DisposalGroupIncludingDiscontinuedOperationLandNetValue us-gaap:DisposalGroupClassification

cli:DisposalGroupIncludingDiscontinuedOperationLandNetValue

us-gaap:DisposalGroupNotDiscontinuedOperations


Disposal
Period End2020-12-312020-09-302020-06-302020-03-31
Value1.9510.00.011
Percentage of DisposalGroupIncludingDiscontinuedOperationLandNetValue100.00.00.0100.0

cli:DisposalGroupIncludingDiscontinuedOperationLandNetValue us-gaap:DisposalGroupClassification, us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations

us-gaap:DisposalGroupNotDiscontinuedOperations, cli:CapitalOfficeParkLand


Disposal
Period End2020-12-312020-09-302020-06-302020-03-31
Value0.00.00.08.21
Percentage of DisposalGroupIncludingDiscontinuedOperationLandNetValue0.00.00.073.4

us-gaap:DisposalGroupNotDiscontinuedOperations, cli:TwoThirtyAndTwoFiftyHalfMileRoad


Disposal
Period End2020-12-312020-09-302020-06-302020-03-31
Value0.00.00.02.969
Percentage of DisposalGroupIncludingDiscontinuedOperationLandNetValue0.00.00.026.6

cli:DisposalGroupIncludingDiscontinuedOperationPropertyPlantAndEquipmentNetValue us-gaap:DisposalGroupClassification

cli:DisposalGroupIncludingDiscontinuedOperationPropertyPlantAndEquipmentNetValue

us-gaap:DisposalGroupNotDiscontinuedOperations


Disposal
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value3622601052150.0173430.04028519190.0164642698.27142
Percentage of DisposalGroupIncludingDiscontinuedOperationPropertyPlantAndEquipmentNetValue100.0100.0100.0100.00.0100.0100.00.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0

cli:DisposalGroupIncludingDiscontinuedOperationPropertyPlantAndEquipmentNetValue us-gaap:DisposalGroupClassification, us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations

us-gaap:DisposalGroupNotDiscontinuedOperations, cli:MetroparkPortfolio


Disposal
Period End2021-06-302021-03-31
Value0.0233
Percentage of DisposalGroupIncludingDiscontinuedOperationPropertyPlantAndEquipmentNetValue0.089.8

us-gaap:DisposalGroupNotDiscontinuedOperations, cli:MorrisPortfolio


Disposal
Period End2020-12-31
Value0.0
Percentage of DisposalGroupIncludingDiscontinuedOperationPropertyPlantAndEquipmentNetValue0.0

us-gaap:DisposalGroupNotDiscontinuedOperations, cli:NineCampusDrive


Disposal
Period End2020-12-31
Value0.0
Percentage of DisposalGroupIncludingDiscontinuedOperationPropertyPlantAndEquipmentNetValue0.0

us-gaap:DisposalGroupNotDiscontinuedOperations, cli:OneBridgePlaza


Disposal
Period End2020-12-312020-09-302020-06-302020-03-31
Value0.00.00.017
Percentage of DisposalGroupIncludingDiscontinuedOperationPropertyPlantAndEquipmentNetValue0.00.00.0100.0

us-gaap:DisposalGroupNotDiscontinuedOperations, cli:OneHundredOverlookCenter


Disposal
Period End2021-06-302021-03-31
Value0.026
Percentage of DisposalGroupIncludingDiscontinuedOperationPropertyPlantAndEquipmentNetValue0.010.2

us-gaap:DisposalGroupNotDiscontinuedOperations, cli:ThreeGiraldaFarms


Disposal
Period End2020-12-31
Value0.0
Percentage of DisposalGroupIncludingDiscontinuedOperationPropertyPlantAndEquipmentNetValue0.0

us-gaap:DisposalGroupNotDiscontinuedOperations, cli:ThreeTwentyFiveColumbiaTurnpike


Disposal
Period End2020-12-31
Value0.0
Percentage of DisposalGroupIncludingDiscontinuedOperationPropertyPlantAndEquipmentNetValue0.0

cli:DistributionsInExcessOfCumulativeEarningsFromJvs

cli:DistributionsInExcessOfCumulativeEarningsFromJvs


Distributions
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value3.5421.4071.8666.0851.4794.3963.721.3752.0361.5661.8461.9013.2354.5711.1781.531.481.6891.325171.4181.7712.1162.3440.8881.097-0.402350.3810.4563.2360.317191.2330.5190.040.00.9880.182.209-0.298-0.631-2.848
Percentage of DistributionsInExcessOfCumulativeEarningsFromJvs100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0

cli:DistributionsInExcessOfCumulativeEarningsFromJvs dei:LegalEntity

cli:MackCaliRealtyLp


Distributions
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-31
Value3.5421.4071.8666.0851.4794.3963.721.3752.0361.5661.8461.9013.2354.5711.1781.531.481.6891.325171.4181.7712.116
Percentage of DistributionsInExcessOfCumulativeEarningsFromJvs100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:EquityCapitalizationExcessPercent us-gaap:ConsolidatedEntities, us-gaap:RelatedPartyTransactionsByRelatedParty

cli:EquityCapitalizationExcessPercent

cli:RoselandResidentialTrust, cli:RoselandResidentialL.p.


Equity
Period End2021-06-302021-03-31
Value010.0
Percentage of EquityCapitalizationExcessPercent0.0100.0

cli:EquityMethodInvestmentAmortizationOfBasisDifference

cli:EquityMethodInvestmentAmortizationOfBasisDifference


Equity
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value143000.0143000.0143000.0143000.0152000.0154000.0156000.0156000.0172000.094000.0230000.0289000.0289000.0-46000.0289000.0289000.0259000.0
Percentage of EquityMethodInvestmentAmortizationOfBasisDifference100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:EstimatedCostOfProject us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty

cli:EstimatedCostOfProject

cli:HarborsideFinancialCenterPlazaFive


Estimated
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-31
Value0.01700.00.00.01700.00.00.01700.00.00.01700.00.00.01700.00.00.01700.00.00.01700.00.00.01700.0
Percentage of EstimatedCostOfProject0.0100.00.00.00.0100.00.00.00.0100.00.00.00.0100.00.00.00.0100.00.00.00.0100.00.00.00.0100.00.00.00.0100.00.0

cli:HarborsideFinancialCenterPlazaFoura


Estimated
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-31
Value0.0490.00.00.0490.00.00.0490.00.00.0490.00.00.0490.00.00.0490.00.00.0490.00.00.0490.0
Percentage of EstimatedCostOfProject0.029.00.00.00.029.00.00.00.029.00.00.00.029.00.00.00.029.00.00.00.029.00.00.00.029.00.00.00.029.00.0

cli:PortImperialSouthNine


Estimated
Period End2021-06-302021-03-312020-12-312020-09-30
Value0.01430.90.0
Percentage of EstimatedCostOfProject0.084.10.00.0

cli:TwentyFiveChristopherColumbus


Estimated
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value0.04690.00.00.0469-1.00.0-0.1470
Percentage of EstimatedCostOfProject0.0274.70.00.00.0274.70.00.00.0275.4

cli:GainLossOnDispositionOfLandDiscontinuedOperations us-gaap:DisposalGroupClassification

cli:GainLossOnDispositionOfLandDiscontinuedOperations

us-gaap:DisposalGroupNotDiscontinuedOperations


Gain
Period End2020-12-312020-09-302020-06-302020-03-31
Value0.9740.00.04.813
Percentage of GainLossOnDispositionOfLandDiscontinuedOperations100.00.00.0100.0

cli:GainLossOnDispositionOfLandDiscontinuedOperations us-gaap:DisposalGroupClassification, us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations

us-gaap:DisposalGroupNotDiscontinuedOperations, cli:CapitalOfficeParkLand


Gain
Period End2020-12-312020-09-302020-06-302020-03-31
Value0.00.00.00.764
Percentage of GainLossOnDispositionOfLandDiscontinuedOperations0.00.00.015.9

us-gaap:DisposalGroupNotDiscontinuedOperations, cli:TwoThirtyAndTwoFiftyHalfMileRoad


Gain
Period End2020-12-312020-09-302020-06-302020-03-31
Value0.00.00.04.049
Percentage of GainLossOnDispositionOfLandDiscontinuedOperations0.00.00.084.1

cli:GainLossOnDispositionOfRealEstateDiscontinuedOperationsNetOfUnrealizedGainLosses

cli:GainLossOnDispositionOfRealEstateDiscontinuedOperationsNetOfUnrealizedGainLosses


Gain
Period End2020-09-302020-06-302020-03-31
Value0.00.0-7.915
Percentage of GainLossOnDispositionOfRealEstateDiscontinuedOperationsNetOfUnrealizedGainLosses0.00.0100.0

cli:GainLossOnDispositionOfRealEstateDiscontinuedOperationsNetOfUnrealizedGainLosses us-gaap:DisposalGroupClassification

us-gaap:DisposalGroupNotDiscontinuedOperations


Gain
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value2.08222915-11.929-27.746
Percentage of GainLossOnDispositionOfRealEstateDiscontinuedOperationsNetOfUnrealizedGainLosses0.00.00.00.00.0350.5

cli:GainLossOnSaleOfRealizedAndUnrealizedPropertyPlantEquipment

cli:GainLossOnSaleOfRealizedAndUnrealizedPropertyPlantEquipment


Gain
Period End2021-06-302020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-30
Value0.1110.9740.00.04.813-0.0440.2960.27
Percentage of GainLossOnSaleOfRealizedAndUnrealizedPropertyPlantEquipment100.0100.00.00.0100.0100.0100.0100.0

cli:GainLossOnSaleOfRealizedAndUnrealizedPropertyPlantEquipment dei:LegalEntity

cli:MackCaliRealtyLp


Gain
Period End2021-06-302020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-30
Value0.1110.9740.00.04.813-0.0440.2960.27
Percentage of GainLossOnSaleOfRealizedAndUnrealizedPropertyPlantEquipment100.0100.00.00.0100.0100.0100.0100.0

cli:ImpairmentOfLandAndOther

cli:ImpairmentOfLandAndOther


Impairment
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-30
Value7.5190.413-6.5841.292165.263236.3452.499
Percentage of ImpairmentOfLandAndOther100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:ImpairmentOfLandAndOther dei:LegalEntity

cli:MackCaliRealtyLp


Impairment
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-30
Value7.5190.413-6.5841.292165.263236.3452.499
Percentage of ImpairmentOfLandAndOther100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:ImpairmentOfLandAndOther us-gaap:MortgageLoansOnRealEstateDescriptionTypeOfProperty

cli:LandParcels


Impairment
Period End2021-06-30
Value7.5
Percentage of ImpairmentOfLandAndOther99.7

cli:ImpairmentOfLandAndOther us-gaap:MortgageLoansOnRealEstateDescriptionTypeOfProperty, us-gaap:DisposalGroupClassification

cli:LandParcels, us-gaap:DisposalGroupNotDiscontinuedOperations


Impairment
Period End2021-06-30
Value7.5
Percentage of ImpairmentOfLandAndOther99.7

cli:ImpairmentOfLandAndOther us-gaap:StatementGeographical

cli:ParsippanyMadisonShortHillsEdisonAndRedBankNewJersey


Impairment
Period End2020-09-30
Value1.3
Percentage of ImpairmentOfLandAndOther100.6

cli:ImpairmentOfLandAndOther us-gaap:StatementGeographical, us-gaap:DisposalGroupClassification

cli:ParsippanyMadisonShortHillsEdisonAndRedBankNewJersey, us-gaap:DisposalGroupHeldforsaleNotDiscontinuedOperations


Impairment
Period End2021-06-302021-03-31
Value0.00.4
Percentage of ImpairmentOfLandAndOther0.096.9

cli:ParsippanyMadisonShortHillsEdisonAndRedBankNewJersey, us-gaap:SegmentDiscontinuedOperations


Impairment
Period End2021-06-302021-03-312020-12-312020-09-30
Value0.40.4-13.91.3
Percentage of ImpairmentOfLandAndOther5.396.9211.1100.6

cli:ImpairmentOfLandAndOtherIncludingContinuedAndDiscontinuedOperations

cli:ImpairmentOfLandAndOtherIncludingContinuedAndDiscontinuedOperations


Impairment
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-31
Value7.5190.413-6.5841.292165.26323
Percentage of ImpairmentOfLandAndOtherIncludingContinuedAndDiscontinuedOperations100.0100.0100.0100.0100.0100.0100.0

cli:ImpairmentOfLandAndOtherIncludingContinuedAndDiscontinuedOperations dei:LegalEntity

cli:MackCaliRealtyLp


Impairment
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-31
Value7.5190.413-6.5841.292165.26323
Percentage of ImpairmentOfLandAndOtherIncludingContinuedAndDiscontinuedOperations100.0100.0100.0100.0100.0100.0100.0

cli:IncomeAllocationEquivalentPercent us-gaap:TitleOfIndividual, us-gaap:AwardType

cli:IncomeAllocationEquivalentPercent

cli:MichaelJ.DemarcoChiefExecutiveOfficer, cli:AoLtipUnitsAward


Income
Period End2021-06-302021-03-312020-12-31
Value010.00
Percentage of IncomeAllocationEquivalentPercent0.0100.00.0

cli:IncomeFromSaleOfEconomicTaxCreditCertificate us-gaap:MortgageLoansOnRealEstateDescriptionTypeOfProperty, us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName

cli:IncomeFromSaleOfEconomicTaxCreditCertificate

cli:UnconsolidatedJointVentureMultipleFamilyProperties, cli:UrbyAtHarborside


Income
Period End2020-12-31
Value0
Percentage of IncomeFromSaleOfEconomicTaxCreditCertificate0.0

cli:IncomeLossFromContinuingOperationsBasic

cli:IncomeLossFromContinuingOperationsBasic


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value-78.061-24.84422-76.253-45.986-37.52448-57.55-40.75233
Percentage of IncomeLossFromContinuingOperationsBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:IncomeLossFromContinuingOperationsBasic dei:LegalEntity

cli:MackCaliRealtyLp


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value-85.885-27.32824-84.357-50.849-41.48653-63.889-45.247260
Percentage of IncomeLossFromContinuingOperationsBasic110.0110.0110.6110.6110.6110.6110.7111.0111.0111.3

cli:IncomeLossFromContinuingOperationsDiluted

cli:IncomeLossFromContinuingOperationsDiluted


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value-85.885-27.32824-84.357-50.849-41.48653-63.889-45.247260-10.3922.2357-17.306-59.943-44.208-12.02411-7.741161225182319187.7131517
Percentage of IncomeLossFromContinuingOperationsDiluted100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:IncomeLossFromContinuingOperationsDilutedEarningsPerShare

cli:IncomeLossFromContinuingOperationsDilutedEarningsPerShare


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value-78.061-24.84422-76.253-45.986-37.52448-57.55-40.75233
Percentage of IncomeLossFromContinuingOperationsDilutedEarningsPerShare100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:IncomeLossFromContinuingOperationsDilutedEarningsPerShare dei:LegalEntity

cli:MackCaliRealtyLp


Income
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value-85.885-27.328-84.357-50.849-41.486-63.889-45.247260
Percentage of IncomeLossFromContinuingOperationsDilutedEarningsPerShare110.0110.0110.6110.6110.6111.0111.0111.3

cli:IncomeLossFromDiscontinuedOperationsAvailableToCommonShareholders

cli:IncomeLossFromDiscontinuedOperationsAvailableToCommonShareholders


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-06-30
Value4.4323038318.863-5.204-106.222-1.4031.9377.391-1.443331.667-2.4310.224-1.1563.3532.929-0.0910.1650.1213.823
Percentage of IncomeLossFromDiscontinuedOperationsAvailableToCommonShareholders100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:IncomeLossFromDiscontinuedOperationsAvailableToCommonShareholders dei:LegalEntity

cli:MackCaliRealtyLp


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value4.8763342359.8-5.753-117.539-1.5572.158.228
Percentage of IncomeLossFromDiscontinuedOperationsAvailableToCommonShareholders110.0110.0110.7110.6110.6110.5110.7111.0111.0111.3

cli:IncreaseDecreaseImpairmentOfLandAndOt

cli:IncreaseDecreaseImpairmentOfLandAndOt


Increase
Period End2020-12-312020-09-302020-06-30
Value002500000.0
Percentage of IncreaseDecreaseImpairmentOfLandAndOt0.00.0100.0

cli:IncreaseDecreaseInRentsReceivedInAdvanceAndSecurityDeposits

cli:IncreaseDecreaseInRentsReceivedInAdvanceAndSecurityDeposits


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value488000.0296000.0-1005000.0870000.02821000.0-5132000.01193000.07266000.01327000.0-7784000.03847000.0-117000.0-737000.0-2118000.0-1097000.0-6319000.01708000.03891000.0-1872000.0-866000.0-929000.0370000.02094000.0-1449000.01664000.0-4717000.04355000.0-1140000.0-1244000.0-3554000.07872000.0-3301000.0-3419000.0-3339000.05370000.0-2673000.0-405000.0606000.0794000.0-3326000.02248000.0-4575000.08164000.0-1074000.0-894000.0-3012000.0
Percentage of IncreaseDecreaseInRentsReceivedInAdvanceAndSecurityDeposits100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:IncreaseDecreaseInRentsReceivedInAdvanceAndSecurityDeposits dei:LegalEntity

cli:MackCaliRealtyLp


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-31
Value488000.0296000.0-1005000.0870000.02821000.0-5132000.01193000.07266000.01327000.0-7784000.03847000.0-117000.0-737000.0-2118000.0-1097000.0-6319000.01708000.03891000.0-1872000.0-866000.0-929000.0370000.02094000.0
Percentage of IncreaseDecreaseInRentsReceivedInAdvanceAndSecurityDeposits100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:IncreaseDecreaseInUnbilledRentReceivables

cli:IncreaseDecreaseInUnbilledRentReceivables


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-30
Value2.4390.9641.885-0.235-1.9071.392-2.3372.9153.9552.7892.2951.727-0.2913.7880.0165.3432.9772.952.9153.1154.5762.1691.7770.784-0.454-0.347-0.3940.9260.6432.9081.6010.2881.8816.3354.050.8280.8540.7562.4250.861
Percentage of IncreaseDecreaseInUnbilledRentReceivables100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:IncreaseDecreaseInUnbilledRentReceivables dei:LegalEntity

cli:MackCaliRealtyLp


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-31
Value2.4390.9641.885-0.235-1.9071.392-2.3372.9153.9552.7892.2951.727-0.2913.7880.0165.3432.9772.952.9153.1154.5762.1691.777
Percentage of IncreaseDecreaseInUnbilledRentReceivables100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:InternalRateOfReturnPercent us-gaap:ConsolidatedEntities, us-gaap:StatementScenario, us-gaap:RelatedPartyTransactionsByRelatedParty

cli:InternalRateOfReturnPercent

cli:RockpointGroupL.l.c., cli:CashFlowFromCapitalEventsDistributionFive, cli:RoselandResidentialL.p.


Internal
Period End2021-06-302021-03-31
Value011.0
Percentage of InternalRateOfReturnPercent0.0100.0

cli:InvestmentIncomeLossNonoperating

cli:InvestmentIncomeLossNonoperating


Investment
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value95000.017000.01000.03000.07000.032000.0884000.0189000.0515000.0824000.0769000.0851000.0641000.01128000.01408000.0762000.0122000.0474000.0875000.01262000.0146000.0-669000.0231000.05000.0291000.0267000.0
Percentage of InvestmentIncomeLossNonoperating100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:InvestmentIncomeLossNonoperating dei:LegalEntity

cli:MackCaliRealtyLp


Investment
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-30
Value95000.017000.01000.03000.07000.032000.0884000.0189000.0515000.0824000.0769000.0851000.0641000.01128000.01408000.0762000.0122000.0474000.0875000.01262000.0146000.0-669000.0231000.05000.0
Percentage of InvestmentIncomeLossNonoperating100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:LeasingPersonnelCosts

cli:LeasingPersonnelCosts


Leasing
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value-2346000.02128000.0663000.01038000.0443000.0534000.0542000.0742000.0
Percentage of LeasingPersonnelCosts100.0100.0100.0100.0100.0100.0100.0100.0

cli:ManagementLeasingDevelopmentAndOtherServicesFees

cli:ManagementLeasingDevelopmentAndOtherServicesFees


Management
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-30
Value1500000.0300000.0600000.0500000.0600000.0600000.0500000.0300000.0500000.0600000.0600000.02200000.0700000.0700000.0700000.0900000.01000000.01000000.01100000.01300000.01400000.01600000.01100000.01900000.01400000.0504000.01600000.01700000.01300000.0
Percentage of ManagementLeasingDevelopmentAndOtherServicesFees100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:MaximumPerformanceSalesVolume us-gaap:TitleOfIndividual, us-gaap:AwardType

cli:MaximumPerformanceSalesVolume

cli:RicardoCardoso, cli:LongTermIncentivePlanAwards


Maximum
Period End2020-11-03
Value900
Percentage of MaximumPerformanceSalesVolume100.0

cli:MinorityInterestDecreaseFromNoncontrollingInterest us-gaap:StatementEquityComponents

cli:MinorityInterestDecreaseFromNoncontrollingInterest

us-gaap:NoncontrollingInterest


Minority
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302017-09-302017-06-302017-03-31
Value-0.175-0.010.00.083-0.2160.00.308-9.418-22.735-0.0510.0011.0670.014
Percentage of MinorityInterestDecreaseFromNoncontrollingInterest100.0100.00.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0

cli:MinorityInterestIncreaseDecreaseFromRedemptions dei:LegalEntity, us-gaap:PartnerTypeOfPartnersCapitalAccount

cli:MinorityInterestIncreaseDecreaseFromRedemptions

cli:MackCaliRealtyLp, cli:GeneralPartnerCommonUnitholders


Minority
Period End2021-06-302019-12-312019-09-302019-06-302019-03-312018-12-312018-09-30
Value2716000.0-1410000.00623000.082000.0203000.0400000.0
Percentage of MinorityInterestIncreaseDecreaseFromRedemptions100.0100.00.0100.0100.0100.0100.0

cli:MackCaliRealtyLp, cli:LimitedPartnersCommonUnitholders


Minority
Period End2021-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-30
Value-2716000.0-2141000.01410000.0-65000.0-623000.0-82000.0-203000.0-400000.0
Percentage of MinorityInterestIncreaseDecreaseFromRedemptions-100.00.0-100.00.0-100.0-100.0-100.0-100.0

cli:MackCaliRealtyLp, us-gaap:LimitedPartner


Minority
Period End2021-06-30
Value-175000.0
Percentage of MinorityInterestIncreaseDecreaseFromRedemptions-6.4

cli:MinorityInterestIncreaseDecreaseFromRedemptions us-gaap:PartnerTypeOfPartnersCapitalAccount

cli:GeneralPartnerCommonUnitholders


Minority
Period End2021-06-302019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value2716000.00623000.082000.0400000.051000.03690000.0
Percentage of MinorityInterestIncreaseDecreaseFromRedemptions100.00.0100.0100.0100.00.00.0

cli:MinorityInterestIncreaseDecreaseFromRedemptions us-gaap:StatementEquityComponents

us-gaap:AdditionalPaidInCapital


Minority
Period End2021-06-302019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value2714000.0-1408000.00622000.082000.0-8479000.0399000.051000.03688000.0-5060000.0
Percentage of MinorityInterestIncreaseDecreaseFromRedemptions99.999.90.099.8100.0-4176.899.80.00.00.0

us-gaap:CommonStock


Minority
Period End2021-06-302019-12-312019-09-302019-06-302018-12-312018-09-302018-06-302018-03-312017-12-31
Value2000.0-2000.001000.0-6000.01000.002000.0-2000.0
Percentage of MinorityInterestIncreaseDecreaseFromRedemptions0.10.10.00.2-3.00.20.00.00.0

us-gaap:NoncontrollingInterest


Minority
Period End2021-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-31
Value-2716000.0-2141000.01410000.0-65000.0-623000.0-82000.08485000.0-400000.0-51000.0-3690000.05062000.000-2531000.0782000.0
Percentage of MinorityInterestIncreaseDecreaseFromRedemptions-100.00.0-100.00.0-100.0-100.04179.8-100.00.00.00.00.00.00.00.0

cli:MonthlyCashInvestmentWithoutRestrictionMaximum us-gaap:ShareRepurchaseProgram

cli:MonthlyCashInvestmentWithoutRestrictionMaximum

cli:DividendReinvestmentAndStockPurchasePlan


Monthly
Period End2021-06-302021-03-31
Value05000.0
Percentage of MonthlyCashInvestmentWithoutRestrictionMaximum0.0100.0

cli:MonthlySalaryAndWageOfficer us-gaap:RelatedPartyTransactionsByRelatedParty

cli:MonthlySalaryAndWageOfficer

cli:MagPartners2.0Llc


Monthly
Period End2021-06-302021-03-312020-07-25
Value0150000.0150000.0
Percentage of MonthlySalaryAndWageOfficer0.0100.0100.0

cli:NoncontrollingInterestEstimatedRedemptionValue us-gaap:ConsolidatedEntities

cli:NoncontrollingInterestEstimatedRedemptionValue

cli:RockpointGroupL.l.c.


Noncontrolling
Period End2021-06-302021-03-31
Value-2.0476
Percentage of NoncontrollingInterestEstimatedRedemptionValue100.0100.0

cli:NoncontrollingInterestInDiscontinuedOperations

cli:NoncontrollingInterestInDiscontinuedOperations


Noncontrolling
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-06-302010-03-31
Value444000.03067000.04104000.03388000.0937000.0549000.0-11317000.0-154000.0213000.0-837000.0-187000.05948000.04630000.0230000.0-748000.031000.0-160000.0466000.0153000.0-13000.024000.019000.0635000.033000.0
Percentage of NoncontrollingInterestInDiscontinuedOperations100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:NoncontrollingInterestIncreaseDecreaseFromSubsidiaryEquityIssuance us-gaap:PartnerTypeOfPartnersCapitalAccount

cli:NoncontrollingInterestIncreaseDecreaseFromSubsidiaryEquityIssuance

cli:GeneralPartnerCommonUnitholders


Noncontrolling
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value-2000000.01556000.0-875000.01611000.0742000.01426000.01778000.0-1563000.0937000.0287000.0560000.0
Percentage of NoncontrollingInterestIncreaseDecreaseFromSubsidiaryEquityIssuance100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:NoncontrollingInterestIncreaseDecreaseFromSubsidiaryEquityIssuance us-gaap:StatementEquityComponents

us-gaap:AdditionalPaidInCapital


Noncontrolling
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-31
Value-2000000.01556000.01142000.0-875000.01611000.0742000.0117000.01426000.01778000.0-1563000.0367000.0937000.0287000.0560000.0866000.0869000.02445000.0443000.0495000.0
Percentage of NoncontrollingInterestIncreaseDecreaseFromSubsidiaryEquityIssuance100.0100.00.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.00.00.00.00.00.0

us-gaap:NoncontrollingInterest


Noncontrolling
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-31
Value2000000.0-1556000.0-1142000.0875000.0-1611000.0-742000.0-117000.0-1426000.0-1778000.01563000.0-367000.0-937000.0-287000.0-560000.0-866000.0-869000.0-2445000.0-443000.0-495000.0-351000.0-396000.0-118000.0150000.0
Percentage of NoncontrollingInterestIncreaseDecreaseFromSubsidiaryEquityIssuance-100.0-100.00.0-100.0-100.0-100.00.0-100.0-100.0-100.00.0-100.0-100.0-100.00.00.00.00.00.00.00.00.00.0

cli:NoncontrollingInterestIncreaseFromDistributionsToNoncontrollingInterestHolders

cli:NoncontrollingInterestIncreaseFromDistributionsToNoncontrollingInterestHolders


Noncontrolling
Period End2021-06-302021-03-312020-09-302020-06-30
Value639000.04000.0-2029000.0790000.0
Percentage of NoncontrollingInterestIncreaseFromDistributionsToNoncontrollingInterestHolders100.0100.0100.0100.0

cli:NoncontrollingInterestIncreaseFromDistributionsToNoncontrollingInterestHolders dei:LegalEntity

cli:MackCaliRealtyLp


Noncontrolling
Period End2021-06-302021-03-312020-09-302020-06-30
Value639000.04000.0-20171000.0790000.0
Percentage of NoncontrollingInterestIncreaseFromDistributionsToNoncontrollingInterestHolders100.0100.0994.1100.0

cli:NoncontrollingInterestIncreaseFromDistributionsToNoncontrollingInterestHolders dei:LegalEntity, us-gaap:PartnerTypeOfPartnersCapitalAccount

cli:MackCaliRealtyLp, cli:GeneralPartnerCommonUnitholders


Noncontrolling
Period End2020-09-30
Value-18142000.0
Percentage of NoncontrollingInterestIncreaseFromDistributionsToNoncontrollingInterestHolders894.1

cli:MackCaliRealtyLp, cli:LimitedPartnersCommonUnitholders


Noncontrolling
Period End2021-06-302021-03-312020-09-302020-06-30
Value639000.04000.0-2029000.0790000.0
Percentage of NoncontrollingInterestIncreaseFromDistributionsToNoncontrollingInterestHolders100.0100.0100.0100.0

cli:NoncontrollingInterestIncreaseFromDistributionsToNoncontrollingInterestHolders us-gaap:StatementEquityComponents

us-gaap:NoncontrollingInterest


Noncontrolling
Period End2021-06-302021-03-312020-09-302020-06-30
Value639000.04000.0-2029000.0790000.0
Percentage of NoncontrollingInterestIncreaseFromDistributionsToNoncontrollingInterestHolders100.0100.0100.0100.0

cli:NoncontrollingInterestRedemptionValueAdjustmentRedeemable

cli:NoncontrollingInterestRedemptionValueAdjustmentRedeemable


Noncontrolling
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value6.4716.4716.476.4716.4716.4716.4716.4715.0064.6674.4063.7852.9892.7992.6832.6832.6820.792
Percentage of NoncontrollingInterestRedemptionValueAdjustmentRedeemable100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:NoncontrollingInterestRedemptionValueAdjustmentRedeemable dei:LegalEntity

cli:MackCaliRealtyLp


Noncontrolling
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value6.4716.4716.476.4716.4716.4716.4716.4715.0064.6674.4063.7852.9892.7992.6832.6832.6820.792
Percentage of NoncontrollingInterestRedemptionValueAdjustmentRedeemable100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:NoncontrollingInterestRedemptionValueAdjustmentRedeemable us-gaap:PartnerTypeOfPartnersCapitalAccount

cli:GeneralPartnerCommonUnitholders


Noncontrolling
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value1.551.7912.1672.2362.8043.025163.1522.6663.3792.754
Percentage of NoncontrollingInterestRedemptionValueAdjustmentRedeemable24.027.733.534.643.346.7334.867.570.4113.098.4

cli:NoncontrollingInterestRedemptionValueAdjustmentRedeemable us-gaap:StatementEquityComponents

us-gaap:NoncontrollingInterest


Noncontrolling
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-31
Value6.6266.656.7016.7086.7676.8056.8565.0244.0873.3733.1122.9992.9761.93
Percentage of NoncontrollingInterestRedemptionValueAdjustmentRedeemable102.4102.8103.6103.7104.6105.2137.0107.6108.0112.8111.2111.8111.0243.7

cli:NoncontrollingInterestRedemptionValueAdjustmentRedeemableBeforeOperatingPartnership

cli:NoncontrollingInterestRedemptionValueAdjustmentRedeemableBeforeOperatingPartnership


Noncontrolling
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value1.551.7914.6072.1672.2362.8042.9493.025163.1522.6262.6663.3792.7542.8122.7282.5519.86
Percentage of NoncontrollingInterestRedemptionValueAdjustmentRedeemableBeforeOperatingPartnership100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:NoncontrollingInterestRedemptionValueAdjustmentRedeemableBeforeOperatingPartnership dei:LegalEntity

cli:MackCaliRealtyLp


Noncontrolling
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value1.7051.975.0982.3972.4733.13.2633.359183.5092.9232.9683.7633.0673.1383.0442.84510
Percentage of NoncontrollingInterestRedemptionValueAdjustmentRedeemableBeforeOperatingPartnership110.0110.0110.7110.6110.6110.6110.6111.0111.0111.3111.3111.3111.4111.4111.6111.6111.5111.5

cli:NoncontrollingInterestRedemptionValueAdjustmentRedeemableInOperatingPartnership

cli:NoncontrollingInterestRedemptionValueAdjustmentRedeemableInOperatingPartnership


Noncontrolling
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value155000.0179000.0491000.0230000.0237000.0296000.0314000.0334000.01850000.0357000.0297000.0302000.0384000.0313000.0326000.0316000.0294000.01138000.0
Percentage of NoncontrollingInterestRedemptionValueAdjustmentRedeemableInOperatingPartnership100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:NonoperatingIncomeExpenseIncludingEquityMethodInvestments

cli:NonoperatingIncomeExpenseIncludingEquityMethodInvestments


Nonoperating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value-59.213-19.04926-18.889-21.551-24.69694-58.255-21.97525956-15.815-17.430-17.98715-67.073-2.068-5.346-37.5362641-24.592-2.83112-30.333-26.966-27.44927-30.795
Percentage of NonoperatingIncomeExpenseIncludingEquityMethodInvestments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:NonoperatingIncomeExpenseIncludingEquityMethodInvestments dei:LegalEntity

cli:MackCaliRealtyLp


Nonoperating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value-59.213-19.04926-18.889-21.551-24.69694-58.255-21.97525956-15.815-17.430-17.98715-67.073-2.068-5.346-37.5362641-24.592-2.83112-30.333
Percentage of NonoperatingIncomeExpenseIncludingEquityMethodInvestments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:NumberOfPayments

cli:NumberOfPayments


Number
Period End2020-09-30
Value3.0
Percentage of NumberOfPayments100.0

cli:OperatingAndInterestExpenses

cli:OperatingAndInterestExpenses


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value74666885707116919494888984969310310197101104101108105101105112120110113141115113117122113111115110113105113117125134137
Percentage of OperatingAndInterestExpenses100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:OperatingAndInterestExpenses us-gaap:StatementBusinessSegments

cli:MultipleFamilyRealEstateAndServicesSegment


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value302223262222212322211819161615161614
Percentage of OperatingAndInterestExpenses41.233.434.931.231.531.9136.526.323.822.521.221.619.116.716.916.216.215.0

cli:RealEstateCommercialAndOtherSegment


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-30
Value161619161516-34.7013535414243435753616063666864656559647268697286747265707070
Percentage of OperatingAndInterestExpenses21.824.327.919.322.622.9-216.239.437.644.648.249.250.959.757.359.259.265.465.365.663.660.962.658.760.964.057.162.863.861.764.963.956.057.562.763.1

us-gaap:CorporateAndOther


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
Value272725423232283136302725252228232920252127382729412830474639414441363940
Percentage of OperatingAndInterestExpenses37.042.237.249.545.945.2179.734.238.532.930.729.229.923.630.523.029.321.124.920.424.532.225.026.129.225.127.240.237.734.737.538.337.332.337.935.5

cli:OperatingLeaseExpenseIncludingSubleaseRentals

cli:OperatingLeaseExpenseIncludingSubleaseRentals


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value0.380.568-0.20.4730.686830001.40.640.640.6296510.60.6080.550.550.80.6260.5990.590.7330.5380.128
Percentage of OperatingLeaseExpenseIncludingSubleaseRentals100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:PartnersCapitalAccountValueUnitsRedeemed us-gaap:DisposalGroupClassification, us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations

cli:PartnersCapitalAccountValueUnitsRedeemed

us-gaap:DisposalGroupNotDiscontinuedOperations, cli:OneHundredOverlookCenter


Partners
Period End2021-03-31
Value10
Percentage of PartnersCapitalAccountValueUnitsRedeemed100.0

cli:PaymentOfClosingCosts us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations

cli:PaymentOfClosingCosts

cli:ShortHillsPortfolio


Payment
Period End2021-06-30
Value22
Percentage of PaymentOfClosingCosts100.0

cli:PaymentsInLieuOfPropertyTaxAsPercentageBasedOnLandValue us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty

cli:PaymentsInLieuOfPropertyTaxAsPercentageBasedOnLandValue

cli:PortImperialSouthOneThirdGarageDevelopment


Payments
Period End2021-06-302021-03-312020-12-31
Value0100.00
Percentage of PaymentsInLieuOfPropertyTaxAsPercentageBasedOnLandValue0.0100.00.0

cli:PaymentsInLieuOfPropertyTaxAsPercentageOfGrossRevenues us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty

cli:PaymentsInLieuOfPropertyTaxAsPercentageOfGrossRevenues

cli:PortImperialSouthElevenDevelopment


Payments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value010.009.900.10000.10000.100
Percentage of PaymentsInLieuOfPropertyTaxAsPercentageOfGrossRevenues0.0100.00.0100.00.0100.00.00.00.0100.00.00.00.0100.00.00.0

cli:PortImperialSouthNine


Payments
Period End2020-09-30
Value9.9
Percentage of PaymentsInLieuOfPropertyTaxAsPercentageOfGrossRevenues100.0

cli:PortImperialSouthParkParcel


Payments
Period End2021-06-302021-03-31
Value010.0
Percentage of PaymentsInLieuOfPropertyTaxAsPercentageOfGrossRevenues0.0100.0

cli:PaymentsInLieuOfPropertyTaxAsPercentageOfGrossRevenues us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty, us-gaap:TaxPeriod

cli:PortImperialSouthNine, cli:YearsElevenToEighteen


Payments
Period End2021-06-302021-03-312020-09-30
Value012.512.375
Percentage of PaymentsInLieuOfPropertyTaxAsPercentageOfGrossRevenues0.0125.0125.0

cli:PortImperialSouthNine, cli:YearsNineteenToTwentyFive


Payments
Period End2021-06-302021-03-312020-09-30
Value014.013.86
Percentage of PaymentsInLieuOfPropertyTaxAsPercentageOfGrossRevenues0.0140.0140.0

cli:PaymentsInLieuOfPropertyTaxAsPercentageOfTotalProjectCost us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty

cli:PaymentsInLieuOfPropertyTaxAsPercentageOfTotalProjectCost

cli:MonacoTowers


Payments
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value010.09.900.1000.1
Percentage of PaymentsInLieuOfPropertyTaxAsPercentageOfTotalProjectCost0.0100.0100.00.0100.00.00.0100.0

cli:PaymentsInLieuOfPropertyTaxAsPercentageOfTotalProjectCost us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty, us-gaap:TaxPeriod

cli:MarbellaIi, cli:YearsFiveToEight


Payments
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value012.011.8800.12000.12
Percentage of PaymentsInLieuOfPropertyTaxAsPercentageOfTotalProjectCost0.0120.0120.00.0120.00.00.0120.0

cli:MarbellaIi, cli:YearsNineToTen


Payments
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value014.013.8600.14000.14
Percentage of PaymentsInLieuOfPropertyTaxAsPercentageOfTotalProjectCost0.0140.0140.00.0140.00.00.0140.0

cli:MarbellaIi, cli:YearsOneToFour


Payments
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value010.09.900.1000.1
Percentage of PaymentsInLieuOfPropertyTaxAsPercentageOfTotalProjectCost0.0100.0100.00.0100.00.00.0100.0

cli:PortImperialSouthNine, cli:YearsOneToTen


Payments
Period End2021-06-302021-03-312020-09-30
Value11.011.010.89
Percentage of PaymentsInLieuOfPropertyTaxAsPercentageOfTotalProjectCost0.0110.0110.0

cli:PaymentsInLieuOfPropertyTaxes us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty

cli:PaymentsInLieuOfPropertyTaxes

cli:HarborsideFinancialCenterPlazaFive


Payments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-30
Value1.11.11.21.11.11.11.21.01.11.11.11.11.11.10.11.21.31.31.01.10.9170.8540.80.8540.8540.8540.80.8540.8540.8540.80.8540.8540.8540.80.854
Percentage of PaymentsInLieuOfPropertyTaxes100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:HarborsideFinancialCenterPlazaFoura


Payments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-09-30
Value2640000.2640.3080.2640.2640.2640.3340.2260.270.270.290.270.270.270.10.3450.3490.3490.3020.2790.2710.2470.2480.2470.2470.2470.2480.2470.2470.2470.2480.2470.2470.2470.247
Percentage of PaymentsInLieuOfPropertyTaxes24000000.024.025.724.024.024.027.822.624.524.526.424.524.524.5100.028.826.826.830.225.429.628.931.028.928.928.931.028.928.928.931.028.928.928.928.9

cli:MarbellaIi


Payments
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value0.30.30.20.30.20.30.50.2
Percentage of PaymentsInLieuOfPropertyTaxes27.327.318.227.318.230.045.518.2

cli:MonacoTowers


Payments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value0.00.50.40.30.50.50.50.50.70.40.5350.6350.6160.6140.5375220.5580.548
Percentage of PaymentsInLieuOfPropertyTaxes0.045.533.327.345.545.541.750.063.636.448.657.756.055.8537.546.542.2

cli:OneOneOneRiverRealty


Payments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value0.40.40.30.40.43520000.40.3520.3520.3520.30.3520.3520.3520.3050.3810.3070.3070.58320.306927
Percentage of PaymentsInLieuOfPropertyTaxes36.436.425.036.436.432000000.033.335.232.032.027.332.032.032.0305.031.823.623.658.327.9

cli:PortImperialHotelDevelopment


Payments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value0.50.70.60.50.50.61.60.50.30.3
Percentage of PaymentsInLieuOfPropertyTaxes45.563.650.045.545.554.5133.350.027.327.3

cli:PortImperialSouthElevenDevelopment


Payments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value0.40.30.20.30.30.30.30.20.20.3
Percentage of PaymentsInLieuOfPropertyTaxes36.427.316.727.327.327.325.020.018.227.3

cli:PaymentsToDevelopPropertyAndOtherRelatedCosts

cli:PaymentsToDevelopPropertyAndOtherRelatedCosts


Payments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-30
Value625768807471166650384236
Percentage of PaymentsToDevelopPropertyAndOtherRelatedCosts100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:PaymentsToDevelopPropertyAndOtherRelatedCosts dei:LegalEntity

cli:MackCaliRealtyLp


Payments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-30
Value625768807471166650384236
Percentage of PaymentsToDevelopPropertyAndOtherRelatedCosts100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:PercentOfLineOfCreditOutstanding us-gaap:CreditFacility, us-gaap:DebtInstrument

cli:PercentOfLineOfCreditOutstanding

us-gaap:SecuredDebt, cli:PortImperialSouthEleven


Percent
Period End2021-06-302021-03-31
Value010.0
Percentage of PercentOfLineOfCreditOutstanding0.0100.0

cli:PercentOfLineOfCreditOutstanding us-gaap:CreditFacility, us-gaap:DebtInstrument, us-gaap:LongtermDebtType

us-gaap:SecuredDebt, cli:PortImperialSouthNine, us-gaap:ConstructionLoans


Percent
Period End2021-06-302021-03-312020-12-31
Value010.00
Percentage of PercentOfLineOfCreditOutstanding0.0100.00.0

us-gaap:SecuredDebt, cli:ShortHillsResidential, us-gaap:ConstructionLoans


Percent
Period End2021-06-302021-03-312020-12-31
Value015.00
Percentage of PercentOfLineOfCreditOutstanding0.0150.00.0

cli:PercentOfLineOfCreditOutstanding us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName, us-gaap:LongtermDebtType

cli:PiNorthRiverwalk, us-gaap:ConstructionLoans


Percent
Period End2021-06-302021-03-31
Value010.0
Percentage of PercentOfLineOfCreditOutstanding0.0100.0

cli:PercentageOfAward us-gaap:TitleOfIndividual, us-gaap:PlanName

cli:PercentageOfAward

cli:MessieurDebari, cli:TwoThousandNineteenLongTermIncentivePlan


Percentage
Period End2021-03-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-132019-03-31
Value100.099.001.0000100.01.0
Percentage of PercentageOfAward100.0100.00.0100.00.00.00.0100.0100.0

cli:PercentageOfSharesVested us-gaap:Range, us-gaap:AwardType, us-gaap:PlanName, us-gaap:Vesting

cli:PercentageOfSharesVested

srt:Maximum, us-gaap:PerformanceShares, cli:TwoThousandThirteenIncentiveStockPlan, cli:ShareBasedCompensationAwardThreeYearsPeriod


Percentage
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312015-06-05
Value148.501.5001.51.5
Percentage of PercentageOfSharesVested100.00.0100.00.00.0100.0100.0

cli:PerformanceBasedVestingConditionsPercentage us-gaap:TitleOfIndividual

cli:PerformanceBasedVestingConditionsPercentage

cli:AnnaMalhariEvpAndCoo


Performance
Period End2021-06-10
Value50.0
Percentage of PerformanceBasedVestingConditionsPercentage100.0

cli:PreferredUnitsContributionToObtainEquityUnits us-gaap:ConsolidatedEntities, us-gaap:Range, us-gaap:RelatedPartyTransaction

cli:PreferredUnitsContributionToObtainEquityUnits

cli:RockpointGroupL.l.c., srt:Maximum, cli:AddOnInvestmentAgreement


Preferred
Period End2021-06-302021-03-312020-09-302020-06-302020-03-31
Value0.01540.00.0154
Percentage of PreferredUnitsContributionToObtainEquityUnits0.0100.00.00.0100.0

cli:ProRataDistributionPercent us-gaap:ConsolidatedEntities, us-gaap:PreferredUnitsByName

cli:ProRataDistributionPercent

cli:RockpointGroupL.l.c., cli:PreferredUnits


Pro
Period End2021-06-302021-03-312020-09-302020-06-302020-03-31
Value010.94710.83800.10947
Percentage of ProRataDistributionPercent0.0100.0100.00.0100.0

cli:ProRataDistributionPercent us-gaap:ConsolidatedEntities, us-gaap:StatementScenario, us-gaap:PreferredUnitsByName

cli:RockpointGroupL.l.c., cli:CashFlowFromCapitalEventsDistributionFive, cli:PreferredUnits


Pro
Period End2021-06-302021-03-312020-09-302020-06-302020-03-31
Value021.8921.67100.2189
Percentage of ProRataDistributionPercent0.0200.0200.00.0200.0

cli:RockpointGroupL.l.c., cli:CashFlowFromOperations, cli:PreferredUnits


Pro
Period End2021-06-302021-03-312020-09-302020-06-302020-03-31
Value021.8921.67100.2189
Percentage of ProRataDistributionPercent0.0200.0200.00.0200.0

cli:RoselandResidentialTrust, cli:CashFlowFromCapitalEventsDistributionFive, cli:PreferredUnits


Pro
Period End2021-06-302021-03-312020-09-302020-06-302020-03-31
Value02.652.623500.0265
Percentage of ProRataDistributionPercent0.024.224.20.024.2

cli:RoselandResidentialTrust, cli:CashFlowFromCapitalEventsDistributionSix, cli:PreferredUnits


Pro
Period End2021-06-302021-03-312020-09-302020-06-302020-03-31
Value01.3251.311700.01325
Percentage of ProRataDistributionPercent0.012.112.10.012.1

cli:RoselandResidentialTrust, cli:CashFlowFromOperations, cli:PreferredUnits


Pro
Period End2021-06-302021-03-312020-09-302020-06-302020-03-31
Value02.652.623500.0265
Percentage of ProRataDistributionPercent0.024.224.20.024.2

cli:ProRataDistributionPercent us-gaap:ConsolidatedEntities, us-gaap:StatementScenario, us-gaap:StatementEquityComponents

cli:RoselandResidentialTrust, cli:CashFlowFromCapitalEventsDistributionFive, cli:CommonUnits


Pro
Period End2021-06-302021-03-312020-09-302020-06-302020-03-31
Value075.4674.70500.7546
Percentage of ProRataDistributionPercent0.0689.3689.30.0689.3

cli:RoselandResidentialTrust, cli:CashFlowFromCapitalEventsDistributionSix, cli:CommonUnits


Pro
Period End2021-06-302021-03-312020-09-302020-06-302020-03-31
Value087.72886.85100.87728
Percentage of ProRataDistributionPercent0.0801.4801.40.0801.4

cli:RoselandResidentialTrust, cli:CashFlowFromOperations, cli:CommonUnits


Pro
Period End2021-06-302021-03-312020-09-302020-06-302020-03-31
Value075.4674.70500.7546
Percentage of ProRataDistributionPercent0.0689.3689.30.0689.3

cli:ProRataDistributionPercentCashFlowFromCapitalEvents us-gaap:ConsolidatedEntities, us-gaap:StatementScenario, us-gaap:RelatedPartyTransactionsByRelatedParty

cli:ProRataDistributionPercentCashFlowFromCapitalEvents

cli:RockpointGroupL.l.c., cli:CashFlowFromCapitalEventsDistributionSix, cli:RoselandResidentialL.p.


Pro
Period End2021-06-302021-03-31
Value050.0
Percentage of ProRataDistributionPercentCashFlowFromCapitalEvents0.0100.0

cli:ProceedsFromEconomicTaxCreditAnnual us-gaap:MortgageLoansOnRealEstateDescriptionTypeOfProperty, us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName

cli:ProceedsFromEconomicTaxCreditAnnual

cli:UnconsolidatedJointVentureMultipleFamilyProperties, cli:UrbyAtHarborside


Proceeds
Period End2020-12-31
Value0
Percentage of ProceedsFromEconomicTaxCreditAnnual0.0

cli:ProceedsFromEconomicTaxCreditTotal us-gaap:MortgageLoansOnRealEstateDescriptionTypeOfProperty, us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName

cli:ProceedsFromEconomicTaxCreditTotal

cli:UnconsolidatedJointVentureMultipleFamilyProperties, cli:UrbyAtHarborside


Proceeds
Period End2020-12-31
Value0.0
Percentage of ProceedsFromEconomicTaxCreditTotal0.0

cli:ProceedsFromSaleOfBuildingsNet us-gaap:StatementGeographical, us-gaap:DisposalGroupClassification, us-gaap:SubsequentEventType

cli:ProceedsFromSaleOfBuildingsNet

cli:ShortHillsNewJersey, us-gaap:DisposalGroupHeldforsaleNotDiscontinuedOperations, us-gaap:SubsequentEvent


Proceeds
Period End2021-04-30
Value100
Percentage of ProceedsFromSaleOfBuildingsNet100.0

cli:PropertyImpairments

cli:PropertyImpairments


Property
Period End2021-06-30
Value6041000.0
Percentage of PropertyImpairments100.0

cli:PropertyImpairments dei:LegalEntity

cli:MackCaliRealtyLp


Property
Period End2021-06-30
Value6041000.0
Percentage of PropertyImpairments100.0

cli:PropertyNetBookValue

cli:PropertyNetBookValue


Property
Period End2021-06-302021-03-312020-09-302020-06-302020-03-31
Value-330.2415713-896.9898
Percentage of PropertyNetBookValue100.0100.0100.0100.0100.0

cli:PropertyNetBookValue us-gaap:PropertyPlantAndEquipmentByType

cli:PropertyLockUpsExpired


Property
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value-100.01200-100.0-100.0-100.018002000.00.00.013000.0-100.0-100.01500-100.00.0-100.01700
Percentage of PropertyNetBookValue30.3289.20.0-14.011.1200.40.00.00.00.00.00.00.00.00.00.00.00.00.0

cli:RealEstateDevelopmentCostsIncurred

cli:RealEstateDevelopmentCostsIncurred


Real
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312018-12-312018-09-302018-06-302018-03-312013-12-31
Value2.2897252919290.061123177940.06
Percentage of RealEstateDevelopmentCostsIncurred100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0

cli:RealEstateDevelopmentCostsIncurred us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty

cli:EmeryAtOverlookRidge


Real
Period End2020-12-312020-09-302020-06-302020-03-31
Value25291929
Percentage of RealEstateDevelopmentCostsIncurred100.0100.0100.0100.0

cli:ParsippanyNewJersey


Real
Period End2021-06-302021-03-31
Value0.05.1
Percentage of RealEstateDevelopmentCostsIncurred0.05.2

cli:Upton


Real
Period End2021-06-302021-03-31
Value2.2897
Percentage of RealEstateDevelopmentCostsIncurred100.0100.0

cli:RealEstateDevelopmentCostsIncurred us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty, us-gaap:LongtermDebtType

cli:Upton, us-gaap:ConstructionLoans


Real
Period End2021-03-31
Value1.7
Percentage of RealEstateDevelopmentCostsIncurred1.7

cli:RealEstateDevelopmentCostsIncurred us-gaap:RealEstateAndAccumulatedDepreciationDescriptionOfProperty, us-gaap:PropertyPlantAndEquipmentByType

cli:Upton, us-gaap:Land


Real
Period End2021-06-302021-03-31
Value0.02.9
Percentage of RealEstateDevelopmentCostsIncurred0.03.0

cli:RealEstatePropertyOwnedAndInvestmentInterestArea us-gaap:MortgageLoansOnRealEstateDescriptionTypeOfProperty

cli:RealEstatePropertyOwnedAndInvestmentInterestArea

cli:ParkingRetail


Real
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value0.00.1080.00.00.00.108-0.0070.00.00120.11380.00010.0-0.00010.13710.00.00.00.13710.0070.00840.00.12170.00.00.12150.00.00.00.1215
Percentage of RealEstatePropertyOwnedAndInvestmentInterestArea0.0100.00.00.00.0100.0100.00.0100.0100.0100.00.0100.0100.00.00.00.0100.0100.0100.00.0100.00.00.0100.00.00.00.0100.0

cli:UnconsolidatedJointVentureOfficeBuildings


Real
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-31
Value1059990.20.00.00.00.20.00.00.00.20.00.00.00.50.0-0.90.01.40.00.00.05.60.00.00.05.6-0.40.92.22.90.3
Percentage of RealEstatePropertyOwnedAndInvestmentInterestArea0.0185.20.00.00.0185.2-0.00.00.0175.70.00.0-0.0364.70.00.00.01021.20.00.00.04601.50.00.00.04609.10.00.00.02386.80.0

cli:UnconsolidatedJointVentureParkingRetailBuildings


Real
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value0.00.0510.00.00.00.0510.00.00.00.08170.00.00.00.08170.00.00.00.08170.00.00.00.08170.00020.00.00.08150.00.00.00.0815
Percentage of RealEstatePropertyOwnedAndInvestmentInterestArea0.047.20.00.00.047.2-0.00.00.071.80.00.0-0.059.60.00.00.059.60.00.00.067.10.00.00.067.10.00.00.067.1

srt:OfficeBuilding


Real
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value-1.67.1-0.6-1.80.010-0.90.0-0.3110.0
Percentage of RealEstatePropertyOwnedAndInvestmentInterestArea0.06574.10.00.00.09722.212857.10.0-25000.010456.90.0

cli:RealizedGainsLossOnDispositionOfAssetsNet

cli:RealizedGainsLossOnDispositionOfAssetsNet


Realized
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value130.00.0-7.915109-34.6660.255268
Percentage of RealizedGainsLossOnDispositionOfAssetsNet100.00.00.0100.0100.0100.0100.0100.0

cli:RealizedGainsLossOnDispositionOfAssetsNet dei:LegalEntity

cli:MackCaliRealtyLp


Realized
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value130.00.0-7.915109-34.6660.255268
Percentage of RealizedGainsLossOnDispositionOfAssetsNet100.00.00.0100.0100.0100.0100.0100.0

cli:RebalanceOfOwnershipPercentage

cli:RebalanceOfOwnershipPercentage


Rebalance
Period End2021-06-302021-03-312020-12-31
Value-1200000.01600000.01100000.0
Percentage of RebalanceOfOwnershipPercentage100.0100.0100.0

cli:RedeemableNoncontrollingInterestDecreaseFromDistribution us-gaap:ConsolidatedEntities, us-gaap:StatementEquityComponents

cli:RedeemableNoncontrollingInterestDecreaseFromDistribution

cli:RockpointGroupL.l.c., cli:RedeemableNoncontrollingInterests


Redeemable
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value6.0166.0166.0166.0166.0166.0164.5514.212
Percentage of RedeemableNoncontrollingInterestDecreaseFromDistribution100.0100.0100.0100.0100.0100.0100.0100.0

cli:RedeemableNoncontrollingInterestDecreaseFromDistribution us-gaap:PreferredUnitsByName, us-gaap:StatementEquityComponents

cli:SeriesUnitsSeriesOnePreferredLimitedPartnershipUnits, cli:RedeemableNoncontrollingInterests


Redeemable
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value0.4550.4550.4550.4550.4550.4550.4550.4550.4550.4550.4550.4550.4550.4550.4550.4560.4550.265
Percentage of RedeemableNoncontrollingInterestDecreaseFromDistribution7.67.60.07.67.67.60.07.610.010.80.00.00.00.00.00.00.00.0

cli:RedeemableNoncontrollingInterestDecreaseFromDistribution us-gaap:StatementEquityComponents

cli:RedeemableNoncontrollingInterests


Redeemable
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value6.4716.4716.476.4716.4716.4716.4716.4715.0064.6674.4063.7852.9892.7992.6832.6832.6820.792
Percentage of RedeemableNoncontrollingInterestDecreaseFromDistribution107.6107.60.0107.6107.6107.60.0107.6110.0110.80.00.00.00.00.00.00.00.0

cli:RedeemableNoncontrollingInterestRedemptionValueAdjustment

cli:RedeemableNoncontrollingInterestRedemptionValueAdjustment


Redeemable
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value-8.176-8.441-11.568-8.868-8.944-9.571-9.734-9.83-23.615-8.176-7.329-6.753-6.752-5.866-5.821-5.727-5.527-11.79
Percentage of RedeemableNoncontrollingInterestRedemptionValueAdjustment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:RedeemableNoncontrollingInterestRedemptionValueAdjustment dei:LegalEntity

cli:MackCaliRealtyLp


Redeemable
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value-8.176-8.441-11.568-8.868-8.944-9.571-9.734-9.83-23.615-8.176-7.329-6.753-6.752-5.866-5.821-5.727-5.527-11.79
Percentage of RedeemableNoncontrollingInterestRedemptionValueAdjustment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:RedeemableNoncontrollingInterestRedemptionValueAdjustment dei:LegalEntity, us-gaap:PartnerTypeOfPartnersCapitalAccount

cli:MackCaliRealtyLp, cli:GeneralPartnerCommonUnitholders


Redeemable
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value-1.55-1.791-4.607-2.167-2.236-2.804-2.949-3.025-16.759-3.152-2.626-2.666-3.379
Percentage of RedeemableNoncontrollingInterestRedemptionValueAdjustment19.021.239.824.425.029.330.330.871.038.635.839.550.0

cli:MackCaliRealtyLp, cli:LimitedPartnersCommonUnitholders


Redeemable
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value-0.155-0.179-0.491-0.23-0.237-0.296-0.314-0.334-1.85-0.357-0.297-0.302-0.384
Percentage of RedeemableNoncontrollingInterestRedemptionValueAdjustment1.92.14.22.62.63.13.23.47.84.44.14.55.7

cli:MackCaliRealtyLp, us-gaap:OtherOwnershipInterest


Redeemable
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value-6.471-6.471-6.47-6.471-6.471-6.471-6.471-6.471-5.006-4.667-4.406-3.785-2.989
Percentage of RedeemableNoncontrollingInterestRedemptionValueAdjustment79.176.755.973.072.467.666.565.821.257.160.156.044.3

cli:RedeemableNoncontrollingInterestRedemptionValueAdjustment us-gaap:ConsolidatedEntities, us-gaap:StatementEquityComponents

cli:RockpointGroupL.l.c., cli:RedeemableNoncontrollingInterests


Redeemable
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value1.7051.972.3972.4733.13.814183.736
Percentage of RedeemableNoncontrollingInterestRedemptionValueAdjustment-20.9-23.3-27.0-27.6-32.4-38.8-79.0-45.7

cli:RedeemableNoncontrollingInterestRedemptionValueAdjustment us-gaap:StatementEquityComponents

cli:RedeemableNoncontrollingInterests


Redeemable
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value1.7051.975.0982.3972.4733.13.2633.814183.7363.0443.23.8893.1183.1383.0443.2511
Percentage of RedeemableNoncontrollingInterestRedemptionValueAdjustment-20.9-23.3-44.1-27.0-27.6-32.4-33.5-38.8-79.0-45.7-41.5-47.4-57.6-53.2-53.9-53.2-58.8-100.0

us-gaap:AdditionalPaidInCapital


Redeemable
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value-1.55-1.791-4.607-2.167-2.236-2.804-2.949-3.025-16.759-3.152-2.626-2.666-3.379-2.754-2.812-2.728-2.551-9.86
Percentage of RedeemableNoncontrollingInterestRedemptionValueAdjustment19.021.239.824.425.029.330.330.871.038.635.839.550.046.948.347.646.283.6

us-gaap:NoncontrollingInterest


Redeemable
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value-6.626-6.65-6.961-6.701-6.708-6.767-6.785-6.805-6.856-5.024-4.703-4.087-3.373-3.112-3.009-2.999-2.976-1.93
Percentage of RedeemableNoncontrollingInterestRedemptionValueAdjustment81.078.860.275.675.070.769.769.229.061.464.260.550.053.151.752.453.816.4

cli:RedemptionOfCommonUnits

cli:RedemptionOfCommonUnits


Redemption
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value-410000.0-10459000.0-523000.0-29000.00-2141000.0-7769000.0-65000.00-6630000.0
Percentage of RedemptionOfCommonUnits100.0100.0100.0100.00.0100.0100.0100.00.0100.0

cli:RedemptionOfCommonUnits dei:LegalEntity

cli:MackCaliRealtyLp


Redemption
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value-410000.0-10459000.0-29000.00-2141000.0-7769000.0-65000.00-6630000.0
Percentage of RedemptionOfCommonUnits100.0100.0100.00.0100.0100.0100.00.0100.0

cli:RedemptionOfCommonUnits dei:LegalEntity, us-gaap:PartnerTypeOfPartnersCapitalAccount

cli:MackCaliRealtyLp, cli:LimitedPartnersCommonUnitholders


Redemption
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-06-30
Value-410000.0-10459000.0-29000.00-2141000.0-7769000.0-65000.00-4965000.0-51000.0
Percentage of RedemptionOfCommonUnits100.0100.0100.00.0100.0100.0100.00.074.90.0

cli:RedemptionOfCommonUnits us-gaap:StatementEquityComponents

us-gaap:NoncontrollingInterest


Redemption
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value-410000.0-10459000.0-523000.0-29000.00-2141000.0-7769000.0-65000.00-4965000.0
Percentage of RedemptionOfCommonUnits100.0100.0100.0100.00.0100.0100.0100.00.074.9

cli:RedemptionOfCommonUnitsShares dei:LegalEntity, us-gaap:PartnerTypeOfPartnersCapitalAccount

cli:RedemptionOfCommonUnitsShares

cli:MackCaliRealtyLp, us-gaap:LimitedPartner


Redemption
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value-25000.0-678000.0-2000.00-98000.0-361000.0-3000.00-301000.0
Percentage of RedemptionOfCommonUnitsShares100.0100.0100.00.0100.0100.0100.00.0100.0

cli:ReimbursementForRelocationCosts us-gaap:Range, us-gaap:TitleOfIndividual

cli:ReimbursementForRelocationCosts

srt:Maximum, cli:MahbodNiaChiefExecutiveOfficer


Reimbursement
Period End2021-03-10
Value50000.0
Percentage of ReimbursementForRelocationCosts100.0

cli:ReimbursementOfAttorneysFeesToNegotiateEmploymentAgreement us-gaap:Range, us-gaap:TitleOfIndividual

cli:ReimbursementOfAttorneysFeesToNegotiateEmploymentAgreement

srt:Maximum, cli:MahbodNiaChiefExecutiveOfficer


Reimbursement
Period End2021-03-10
Value100000.0
Percentage of ReimbursementOfAttorneysFeesToNegotiateEmploymentAgreement100.0

cli:ReimbursementOfExpenses

cli:ReimbursementOfExpenses


Reimbursement
Period End2020-09-30
Value6100000.0
Percentage of ReimbursementOfExpenses100.0

cli:ReimbursementOfExpenses dei:LegalEntity

cli:BowStreetLlc


Reimbursement
Period End2020-09-30
Value6100000.0
Percentage of ReimbursementOfExpenses100.0

cli:RestructuringCostsGeneralAndAdministrationExpense us-gaap:RestructuringCostAndReserve

cli:RestructuringCostsGeneralAndAdministrationExpense

us-gaap:EmployeeSeverance


Restructuring
Period End2020-09-30
Value8.2
Percentage of RestructuringCostsGeneralAndAdministrationExpense100.0

cli:RestructuringCostsOperatingServices us-gaap:RestructuringCostAndReserve

cli:RestructuringCostsOperatingServices

us-gaap:EmployeeSeverance


Restructuring
Period End2020-09-30
Value700000.0
Percentage of RestructuringCostsOperatingServices100.0

cli:RightOfFirstRefusalToInvestInPreferredUnitsAmount us-gaap:ConsolidatedEntities, us-gaap:RelatedPartyTransaction

cli:RightOfFirstRefusalToInvestInPreferredUnitsAmount

cli:RockpointGroupL.l.c., cli:AddOnInvestmentAgreement


Right
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-06-30
Value0.01000.00.0100100
Percentage of RightOfFirstRefusalToInvestInPreferredUnitsAmount0.0100.00.00.0100.0100.0

cli:SegmentReportingInformationNetOperatingIncomeLossForReportableSegment

cli:SegmentReportingInformationNetOperatingIncomeLossForReportableSegment


Segment
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value6.6498.3649.048-6.841.45310-62.1540363943424144485557525174474340474037304347274948605754536069
Percentage of SegmentReportingInformationNetOperatingIncomeLossForReportableSegment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:SegmentReportingInformationNetOperatingIncomeLossForReportableSegment dei:LegalEntity

cli:MackCaliRealtyLp


Segment
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-30
Value6.6498.3649.048-6.841.45310-62.154036394342414448555752517447434047
Percentage of SegmentReportingInformationNetOperatingIncomeLossForReportableSegment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:SegmentReportingInformationNetOperatingIncomeLossForReportableSegment us-gaap:StatementBusinessSegments

cli:MultipleFamilyRealEstateAndServicesSegment


Segment
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value9.73313121115192322211313107.6269.4757.5845.294.1242.297
Percentage of SegmentReportingInformationNetOperatingIncomeLossForReportableSegment146.4165.3142.2-172.01068.2193.5-38.154.259.934.831.424.218.221.515.69.67.24.4

cli:RealEstateCommercialAndOtherSegment


Segment
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-30
Value252221221823-57.474950565757595760757871749570696677716670738071828392858687
Percentage of SegmentReportingInformationNetOperatingIncomeLossForReportableSegment377.9273.0232.6-324.81274.5229.892.5120.8139.3143.8131.1135.5142.2130.3125.3136.4137.2136.1143.8127.1149.3160.3163.6163.0174.2177.3226.5167.8169.4261.6164.9170.3153.2148.3159.3163.4

us-gaap:CorporateAndOther


Segment
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value-28.21-28.29-24.86-40.825-32.587-32.555-28.383-30.485-35.917-31.08-27.288-25.311-25.307-22.848-16.27-26.454-28.898-19.905-15.718-23.626-28.539-39.166-29.338-33.887-41.884-30.507-32.556-41.06-42.206-30.149-33.829-43.558-40.905
Percentage of SegmentReportingInformationNetOperatingIncomeLossForReportableSegment-424.3-338.2-274.8596.9-2242.7-323.345.7-75.0-99.2-78.6-62.6-59.7-60.4-51.8-33.5-47.9-50.2-37.9-30.5-31.6-76.4-126.4-67.0-71.4-153.1-61.3-66.8-68.2-73.2-55.3-63.4-71.5-58.6

cli:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAnnualAggregateGrantDateFairValue us-gaap:TitleOfIndividual

cli:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAnnualAggregateGrantDateFairValue

cli:AnnaMalhariEvpAndCoo


Share
Period End2021-06-10
Value100000.0
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAnnualAggregateGrantDateFairValue100.0

cli:MahbodNiaChiefExecutiveOfficer


Share
Period End2021-03-10
Value4000000.0
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAnnualAggregateGrantDateFairValue0.0

cli:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsPercentOfEstimatedNetAssetValue us-gaap:TitleOfIndividual, us-gaap:AwardType

cli:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsPercentOfEstimatedNetAssetValue

cli:RicardoCardoso, cli:LongTermIncentivePlanAwards


Share
Period End2020-11-03
Value85.0
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsPercentOfEstimatedNetAssetValue100.0

cli:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsPercentOfEstimatedNetAssetValue us-gaap:TitleOfIndividual, us-gaap:PlanName

cli:RicardoCardoso, cli:JSeries2021Opp


Share
Period End2020-11-03
Value85.0
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsPercentOfEstimatedNetAssetValue100.0

cli:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsTargetGrantValue us-gaap:TitleOfIndividual, us-gaap:AwardType

cli:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsTargetGrantValue

cli:RicardoCardoso, cli:LongTermIncentivePlanAwards


Share
Period End2020-11-03
Value2000000.0
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsTargetGrantValue100.0

cli:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsThresholdEarningPercentage us-gaap:Range, us-gaap:TitleOfIndividual, us-gaap:AwardType

cli:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsThresholdEarningPercentage

srt:Maximum, cli:RicardoCardoso, cli:LongTermIncentivePlanAwards


Share
Period End2020-11-03
Value200.0
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsThresholdEarningPercentage100.0

srt:Minimum, cli:RicardoCardoso, cli:LongTermIncentivePlanAwards


Share
Period End2020-11-03
Value0
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsThresholdEarningPercentage0.0

cli:ShareBasedCompensationArrangementByShareBasedPaymentAwardThresholdSharePriceTrigger us-gaap:TitleOfIndividual, us-gaap:AwardType, us-gaap:Vesting

cli:ShareBasedCompensationArrangementByShareBasedPaymentAwardThresholdSharePriceTrigger

cli:MichaelJ.DemarcoChiefExecutiveOfficer, cli:AoLtipUnitsAward, us-gaap:ShareBasedCompensationAwardTrancheOne


Share
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value025.000025.000025.0
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardThresholdSharePriceTrigger0.0100.00.00.00.0100.00.00.00.0100.0

cli:MichaelJ.DemarcoChiefExecutiveOfficer, cli:AoLtipUnitsAward, us-gaap:ShareBasedCompensationAwardTrancheThree


Share
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value031.000031.000031.0
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardThresholdSharePriceTrigger0.0124.00.00.00.0124.00.00.00.0124.0

cli:MichaelJ.DemarcoChiefExecutiveOfficer, cli:AoLtipUnitsAward, us-gaap:ShareBasedCompensationAwardTrancheTwo


Share
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value028.000028.000028.0
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardThresholdSharePriceTrigger0.0112.00.00.00.0112.00.00.00.0112.0

cli:StayOnAwardAgreementCosts us-gaap:Range, us-gaap:AwardType

cli:StayOnAwardAgreementCosts

srt:Maximum, cli:StayOnAwardAgreement


Stay
Period End2020-09-30
Value5500000.0
Percentage of StayOnAwardAgreementCosts100.0

cli:StockBasedCompensationAttributableToNoncontrollingInterest us-gaap:PartnerTypeOfPartnersCapitalAccount

cli:StockBasedCompensationAttributableToNoncontrollingInterest

cli:GeneralPartnerCommonUnitholders


Stock
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value1239000.0646000.0394000.0334000.0430000.07000.0218000.0265000.0202000.0434000.0517000.0
Percentage of StockBasedCompensationAttributableToNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:StockBasedCompensationAttributableToNoncontrollingInterest us-gaap:StatementEquityComponents

us-gaap:NoncontrollingInterest


Stock
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-31
Value1304000.01883000.0329000.02105000.02100000.01973000.01973000.01615000.01568000.0223000.02015000.01329000.01329000.0644000.0669000.0669000.0173000.0
Percentage of StockBasedCompensationAttributableToNoncontrollingInterest105.2291.583.5630.2488.428185.7905.0609.4776.251.4389.70.00.00.00.00.00.0

cli:StockIssuedDuringPeriodSharesLongTermIncentivePlanVested dei:LegalEntity, us-gaap:PartnerTypeOfPartnersCapitalAccount

cli:StockIssuedDuringPeriodSharesLongTermIncentivePlanVested

cli:MackCaliRealtyLp, us-gaap:LimitedPartner


Stock
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-30
Value258000.09000.015000.088000.068000.04000.000-9000.077000.000
Percentage of StockIssuedDuringPeriodSharesLongTermIncentivePlanVested100.0100.0100.0100.0100.0100.00.00.0100.0100.00.00.0

cli:StockIssuedDuringPeriodValueLongTermIncentivePlanUnitsForfeited us-gaap:StatementEquityComponents

cli:StockIssuedDuringPeriodValueLongTermIncentivePlanUnitsForfeited

us-gaap:NoncontrollingInterest


Stock
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value00201000.0002889000.0
Percentage of StockIssuedDuringPeriodValueLongTermIncentivePlanUnitsForfeited0.00.0100.00.00.0100.0

cli:TargetPerformanceSalesVolume us-gaap:TitleOfIndividual, us-gaap:AwardType

cli:TargetPerformanceSalesVolume

cli:RicardoCardoso, cli:LongTermIncentivePlanAwards


Target
Period End2020-11-03
Value700
Percentage of TargetPerformanceSalesVolume100.0

cli:ThresholdPerformanceSalesValue us-gaap:TitleOfIndividual, us-gaap:AwardType

cli:ThresholdPerformanceSalesValue

cli:RicardoCardoso, cli:LongTermIncentivePlanAwards


Threshold
Period End2020-11-03
Value500
Percentage of ThresholdPerformanceSalesValue100.0

cli:TimeBasedVestingCondtionsPercentage us-gaap:TitleOfIndividual

cli:TimeBasedVestingCondtionsPercentage

cli:AnnaMalhariEvpAndCoo


Time
Period End2021-06-10
Value50.0
Percentage of TimeBasedVestingCondtionsPercentage100.0

cli:TotalStockholderReturnPercent us-gaap:AwardType, us-gaap:PlanName

cli:TotalStockholderReturnPercent

us-gaap:PerformanceShares, cli:TwentyTwentyOneRsuLtipAwards


Total
Period End2021-04-21
Value36.0
Percentage of TotalStockholderReturnPercent100.0

cli:TotalStockholderReturnPercent us-gaap:AwardType, us-gaap:PlanName, us-gaap:SubsequentEventType

us-gaap:PerformanceShares, cli:TwentyTwentyOneRsuLtipAwards, us-gaap:SubsequentEvent


Total
Period End2021-04-21
Value36.0
Percentage of TotalStockholderReturnPercent100.0

cli:TotalStockholderReturnPercent us-gaap:PlanName

cli:TwoThousandEighteenOutperformancePlan


Total
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value036.0035.6400.360000.360000.36
Percentage of TotalStockholderReturnPercent0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

cli:TwoThousandNineteenOutperformancePlan


Total
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value036.0035.6400.360000.36
Percentage of TotalStockholderReturnPercent0.00.00.00.00.00.00.00.00.00.0

cli:TwoThousandSeventeenOutperformancePlan


Total
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value035.6400.360000.360000.360000.36
Percentage of TotalStockholderReturnPercent0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

cli:TwoThousandTwentyOutperformancePlan


Total
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value036.0035.6400.36
Percentage of TotalStockholderReturnPercent0.00.00.00.00.00.0

cli:UnrealizedGainLossOnDispositionOfRentalProperty

cli:UnrealizedGainLossOnDispositionOfRentalProperty


Unrealized
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302012-06-30
Value-0.9511.021923-11.929-45.068-128.235-10.063-5.802-1.634
Percentage of UnrealizedGainLossOnDispositionOfRentalProperty100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cli:UnrealizedGainLossOnDispositionOfRentalProperty us-gaap:DisposalGroupClassification, us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations

us-gaap:DisposalGroupHeldforsaleNotDiscontinuedOperations, cli:DisposalGroupOne


Unrealized
Period End2021-06-302021-03-31
Value1.0-1.2
Percentage of UnrealizedGainLossOnDispositionOfRentalProperty-105.2-117.6

cli:UnrealizedGainLossOnDispositionOfRentalProperty us-gaap:IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperations

cli:DisposalGroupOne


Unrealized
Period End2020-09-302020-06-302020-03-31
Value-23.7000000000000031145
Percentage of UnrealizedGainLossOnDispositionOfRentalProperty-100.1-99.8-100.1

us-gaap:AdjustmentsToAdditionalPaidInCapitalDividendsInExcessOfRetainedEarnings us-gaap:PartnerTypeOfPartnersCapitalAccount

us-gaap:AdjustmentsToAdditionalPaidInCapitalDividendsInExcessOfRetainedEarnings

cli:GeneralPartnerCommonUnitholders


Adjustments
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value-11000.0-18000.0-9000.0-11000.0-19000.0-10000.0-11000.0-10000.0-13000.082000.0-28000.0
Percentage of AdjustmentsToAdditionalPaidInCapitalDividendsInExcessOfRetainedEarnings100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AmortizationOfFinancingCostsAndDiscounts

us-gaap:AmortizationOfFinancingCostsAndDiscounts


Amortization
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value1283000.0907000.01467000.01074000.01060000.01024000.01147000.01121000.01168000.01189000.01485000.01302000.01145000.01096000.01150000.01184000.01175000.01103000.0999000.01234000.01180000.01169000.0944000.0945000.0948000.0953000.0968000.0778000.0759000.0769000.0793000.0797000.0809000.0773000.0724000.0673000.0661000.0611000.0618000.0584000.0584000.0584000.0635000.0645000.0661000.0715000.0
Percentage of AmortizationOfFinancingCostsAndDiscounts100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AmortizationOfFinancingCostsAndDiscounts dei:LegalEntity

cli:MackCaliRealtyLp


Amortization
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-31
Value1283000.0907000.01467000.01074000.01060000.01024000.01147000.01121000.01168000.01189000.01485000.01302000.01145000.01096000.01150000.01184000.01175000.01103000.0999000.01234000.01180000.01169000.0944000.0
Percentage of AmortizationOfFinancingCostsAndDiscounts100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect


Cash
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value-226.74322814-3.06-0.688-0.041-13.237-24.12745-16.93218-20.843-8.352-7.835-61.2951-148.026140
Percentage of CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect dei:LegalEntity

cli:MackCaliRealtyLp


Cash
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value-226.74322814-3.06-0.688-0.041-13.237-24.12745-16.93218-20.843-8.352-7.835-61.2951-148.026140
Percentage of CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CashProvidedByUsedInInvestingActivitiesDiscontinuedOperations

us-gaap:CashProvidedByUsedInInvestingActivitiesDiscontinuedOperations


Cash
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value32926381205-4.4065618-9.427-14.571-60.451
Percentage of CashProvidedByUsedInInvestingActivitiesDiscontinuedOperations100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CashProvidedByUsedInInvestingActivitiesDiscontinuedOperations dei:LegalEntity

cli:MackCaliRealtyLp


Cash
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value32926381205-4.4065618-9.427-14.571-60.451
Percentage of CashProvidedByUsedInInvestingActivitiesDiscontinuedOperations100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CashProvidedByUsedInOperatingActivitiesDiscontinuedOperations

us-gaap:CashProvidedByUsedInOperatingActivitiesDiscontinuedOperations


Cash
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value-2.3148.7194.85622192722182219
Percentage of CashProvidedByUsedInOperatingActivitiesDiscontinuedOperations100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CashProvidedByUsedInOperatingActivitiesDiscontinuedOperations dei:LegalEntity

cli:MackCaliRealtyLp


Cash
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value-2.3148.7194.85622192722182219
Percentage of CashProvidedByUsedInOperatingActivitiesDiscontinuedOperations100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DeferredCompensationArrangementWithIndividualExercisePrice us-gaap:Range, us-gaap:PlanName

us-gaap:DeferredCompensationArrangementWithIndividualExercisePrice

srt:Maximum, cli:TwoThousandThirteenIncentiveStockPlan


Deferred
Period End2020-12-312020-09-30
Value017.31
Percentage of DeferredCompensationArrangementWithIndividualExercisePrice0.0100.0

srt:Minimum, cli:TwoThousandThirteenIncentiveStockPlan


Deferred
Period End2020-12-312020-09-30
Value014.39
Percentage of DeferredCompensationArrangementWithIndividualExercisePrice0.083.1

us-gaap:DepreciationAndAmortization

us-gaap:DepreciationAndAmortization


Depreciation
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value282829312733-14.92494948464541414752574752484343434442404041444447464846474747474848484847474748
Percentage of DepreciationAndAmortization100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DepreciationAndAmortization dei:LegalEntity

cli:MackCaliRealtyLp


Depreciation
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value282829312733-14.9249494846454141475257475248434343444240
Percentage of DepreciationAndAmortization100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet us-gaap:DerivativeInstrumentRisk, us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship, us-gaap:HedgingDesignation, us-gaap:IncomeStatementLocation

us-gaap:DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet

us-gaap:InterestRateSwap, us-gaap:CashFlowHedging, us-gaap:DesignatedAsHedgingInstrument, us-gaap:InterestExpense


Derivative
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value0016000.0551000.01297000.01571000.0929000.0640000.080000.0
Percentage of DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet0.00.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax

us-gaap:DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax


Discontinued
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302013-12-312013-09-302013-06-30
Value2.08223515-11.929-27.746-120.309-10.063-5.802-1.5594713
Percentage of DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax dei:LegalEntity

cli:MackCaliRealtyLp


Discontinued
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-30
Value2.08223515-11.929-27.746-120.309-10.063-5.802
Percentage of DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DiscontinuedOperationIncomeLossFromDiscontinuedOperationDuringPhaseOutPeriodNetOfTax

us-gaap:DiscontinuedOperationIncomeLossFromDiscontinuedOperationDuringPhaseOutPeriodNetOfTax


Discontinued
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-06-302010-03-31
Value2.796107.5111921212.778.5067.9528.228-0.0092.1641.3641.8971.0440.2430.318-0.1931.207-0.1040.1890.140.0110.231
Percentage of DiscontinuedOperationIncomeLossFromDiscontinuedOperationDuringPhaseOutPeriodNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DiscontinuedOperationIncomeLossFromDiscontinuedOperationDuringPhaseOutPeriodNetOfTax dei:LegalEntity

cli:MackCaliRealtyLp


Discontinued
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value2.796107.5111921212.778.5067.9528.228
Percentage of DiscontinuedOperationIncomeLossFromDiscontinuedOperationDuringPhaseOutPeriodNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DisposalGroupIncludingDiscontinuedOperationDepreciationAndAmortization

us-gaap:DisposalGroupIncludingDiscontinuedOperationDepreciationAndAmortization


Disposal
Peri