Comerica Incorporated
10-K on 02/11/2020   Download
SEC Document
SEC Filing
300000000031000000000.0450.0450.0450.045P90DP90DP90DP90DP5YP30DP90DP90D0.0002P90DP90DP90D100000000800000005000000P90D0false--12-31FY2019false0000028412falsefalsefalse200000095.2595.2595.2567.53P3Y4M24D540000000055000000000.080.080.080.080.1053250000003250000002281648242281648240.0380.021250.040.078750.02500.0370.0400.0380.021250.040.078750.02502026-07-222019-05-232025-07-272026-09-152020-06-022023-07-312029-02-012026-07-222019-05-232026-05-202026-03-042028-01-262025-07-272026-09-152020-06-022024-07-2300.550.452100000021000000P3Y10M24DP3Y0M0DP4Y7M6D0P2Y3M7D163000000850000000000P120DP180D0P9Y0M0D330000000000.0170.01885200000020182017201420062028-12-312019-12-31P33YP8YP10YP3YP3YP5YP4YP5YP5Y0M0DP1YP3YP3Y0M0DP6Y10M24DP7Y4M24DP7Y7M6DP4Y2M12DP5Y3M18D0.040.040.040.04400000000041000000000.060.060.060.060.06680811768606923400 0000028412 2019-01-01 2019-12-31 0000028412 2019-12-31 0000028412 2020-02-07 0000028412 2019-06-28 0000028412 2018-12-31 0000028412 2018-01-01 2018-12-31 0000028412 2017-01-01 2017-12-31 0000028412 us-gaap:AdditionalPaidInCapitalMember 2018-01-01 2018-12-31 0000028412 us-gaap:AdditionalPaidInCapitalMember 2019-12-31 0000028412 us-gaap:AdditionalPaidInCapitalMember 2017-12-31 0000028412 us-gaap:RetainedEarningsMember 2017-01-01 2017-12-31 0000028412 us-gaap:AccumulatedOtherComprehensiveIncomeMember 2018-12-31 0000028412 us-gaap:CommonStockMember 2019-12-31 0000028412 us-gaap:CommonStockMember 2018-12-31 0000028412 2016-12-31 0000028412 us-gaap:AccumulatedOtherComprehensiveIncomeMember 2017-01-01 2017-12-31 0000028412 us-gaap:TreasuryStockMember 2018-01-01 2018-12-31 0000028412 us-gaap:AdditionalPaidInCapitalMember 2016-12-31 0000028412 us-gaap:AccumulatedOtherComprehensiveIncomeMember 2017-12-31 0000028412 us-gaap:RetainedEarningsMember 2018-01-01 2018-12-31 0000028412 us-gaap:AccumulatedOtherComprehensiveIncomeMember 2019-12-31 0000028412 us-gaap:CommonStockMember 2017-01-01 2017-12-31 0000028412 us-gaap:RetainedEarningsMember 2019-01-01 2019-12-31 0000028412 us-gaap:AdditionalPaidInCapitalMember 2017-01-01 2017-12-31 0000028412 us-gaap:CommonStockMember 2019-01-01 2019-12-31 0000028412 us-gaap:CommonStockMember 2018-01-01 2018-12-31 0000028412 us-gaap:AdditionalPaidInCapitalMember 2019-01-01 2019-12-31 0000028412 us-gaap:TreasuryStockMember 2017-01-01 2017-12-31 0000028412 us-gaap:AccumulatedOtherComprehensiveIncomeMember 2018-01-01 2018-12-31 0000028412 2017-12-31 0000028412 us-gaap:AccumulatedOtherComprehensiveIncomeMember 2016-12-31 0000028412 us-gaap:RetainedEarningsMember 2017-12-31 0000028412 us-gaap:RetainedEarningsMember 2019-12-31 0000028412 us-gaap:RetainedEarningsMember 2016-12-31 0000028412 us-gaap:CommonStockMember 2016-12-31 0000028412 us-gaap:CommonStockMember 2017-12-31 0000028412 us-gaap:TreasuryStockMember 2016-12-31 0000028412 us-gaap:RetainedEarningsMember 2018-12-31 0000028412 us-gaap:TreasuryStockMember 2017-12-31 0000028412 us-gaap:AccumulatedOtherComprehensiveIncomeMember 2019-01-01 2019-12-31 0000028412 us-gaap:TreasuryStockMember 2018-12-31 0000028412 us-gaap:TreasuryStockMember 2019-01-01 2019-12-31 0000028412 us-gaap:AdditionalPaidInCapitalMember 2018-12-31 0000028412 us-gaap:TreasuryStockMember 2019-12-31 0000028412 us-gaap:AccountingStandardsUpdate201613Member 2020-01-01 0000028412 us-gaap:CarryingReportedAmountFairValueDisclosureMember 2019-12-31 0000028412 us-gaap:AccountingStandardsUpdate201613Member us-gaap:RetainedEarningsMember 2020-01-01 0000028412 us-gaap:AccountingStandardsUpdate201602Member us-gaap:RetainedEarningsMember 2019-01-01 0000028412 cma:ShortCutMethodMember us-gaap:InterestRateSwapMember us-gaap:FairValueHedgingMember us-gaap:DesignatedAsHedgingInstrumentMember 2019-12-31 0000028412 us-gaap:AccountingStandardsUpdate201602Member 2019-01-01 0000028412 us-gaap:ComputerSoftwareIntangibleAssetMember 2019-01-01 2019-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember cma:ConsumerFinancingReceivableMember 2019-12-31 0000028412 srt:MinimumMember us-gaap:BuildingAndBuildingImprovementsMember 2019-01-01 2019-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember cma:ConsumerFinancingReceivableMember 2019-01-01 2019-12-31 0000028412 srt:MinimumMember us-gaap:FurnitureAndFixturesMember 2019-01-01 2019-12-31 0000028412 srt:MaximumMember us-gaap:FurnitureAndFixturesMember 2019-01-01 2019-12-31 0000028412 us-gaap:ConsumerPortfolioSegmentMember us-gaap:RealEstateLoanMember 2019-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember us-gaap:HomeEquityLoanMember 2019-01-01 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember 2019-01-01 2019-12-31 0000028412 us-gaap:ConsumerPortfolioSegmentMember us-gaap:RealEstateLoanMember 2019-01-01 2019-12-31 0000028412 srt:MaximumMember us-gaap:LeaseholdImprovementsMember 2019-01-01 2019-12-31 0000028412 srt:MaximumMember us-gaap:BuildingAndBuildingImprovementsMember 2019-01-01 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsNonrecurringMember us-gaap:GeographicDistributionDomesticMember 2019-12-31 0000028412 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsNonrecurringMember 2018-12-31 0000028412 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsNonrecurringMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsNonrecurringMember us-gaap:GeographicDistributionDomesticMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsNonrecurringMember us-gaap:RealEstateLoanMember us-gaap:GeographicDistributionDomesticMember 2018-12-31 0000028412 us-gaap:ResidentialMortgageMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsNonrecurringMember us-gaap:GeographicDistributionDomesticMember 2018-12-31 0000028412 us-gaap:FairValueMeasurementsNonrecurringMember 2019-12-31 0000028412 us-gaap:FairValueMeasurementsRecurringMember 2019-01-01 2019-12-31 0000028412 us-gaap:FairValueMeasurementsNonrecurringMember 2018-12-31 0000028412 us-gaap:FairValueMeasurementsRecurringMember 2018-12-31 0000028412 us-gaap:ForeignExchangeContractMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2018-12-31 0000028412 us-gaap:InterestRateContractMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2018-12-31 0000028412 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2018-12-31 0000028412 us-gaap:InterestRateContractMember us-gaap:FairValueMeasurementsRecurringMember 2018-12-31 0000028412 us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:MortgageBackedSecuritiesMember 2018-12-31 0000028412 us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2018-12-31 0000028412 us-gaap:ForeignExchangeContractMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2018-12-31 0000028412 us-gaap:CommodityContractMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2018-12-31 0000028412 us-gaap:ForeignExchangeContractMember us-gaap:FairValueMeasurementsRecurringMember 2018-12-31 0000028412 us-gaap:CommodityContractMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2018-12-31 0000028412 us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember cma:DeferredCompensationPlanAssetsMember 2018-12-31 0000028412 us-gaap:CommodityContractMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2018-12-31 0000028412 us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:MortgageBackedSecuritiesMember 2018-12-31 0000028412 us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:USTreasuryAndGovernmentMember 2018-12-31 0000028412 us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:USTreasuryAndGovernmentMember 2018-12-31 0000028412 us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember cma:DeferredCompensationPlanAssetsMember 2018-12-31 0000028412 us-gaap:FairValueMeasurementsRecurringMember cma:DeferredCompensationPlanAssetsMember 2018-12-31 0000028412 us-gaap:InterestRateContractMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2018-12-31 0000028412 us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2018-12-31 0000028412 us-gaap:CommodityContractMember us-gaap:FairValueMeasurementsRecurringMember 2018-12-31 0000028412 us-gaap:ForeignExchangeContractMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2018-12-31 0000028412 us-gaap:InterestRateContractMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2018-12-31 0000028412 us-gaap:FairValueMeasurementsRecurringMember us-gaap:USTreasuryAndGovernmentMember 2018-12-31 0000028412 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:MortgageBackedSecuritiesMember 2018-12-31 0000028412 us-gaap:FairValueMeasurementsRecurringMember us-gaap:MortgageBackedSecuritiesMember 2018-12-31 0000028412 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember cma:DeferredCompensationPlanAssetsMember 2018-12-31 0000028412 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:USTreasuryAndGovernmentMember 2018-12-31 0000028412 us-gaap:InterestRateContractMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2019-12-31 0000028412 us-gaap:FairValueMeasurementsRecurringMember cma:DeferredCompensationPlanAssetsMember 2019-12-31 0000028412 us-gaap:FairValueMeasurementsRecurringMember 2019-12-31 0000028412 us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2019-12-31 0000028412 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2019-12-31 0000028412 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember cma:DeferredCompensationPlanAssetsMember 2019-12-31 0000028412 us-gaap:FairValueMeasurementsRecurringMember us-gaap:MortgageBackedSecuritiesMember 2019-12-31 0000028412 us-gaap:ForeignExchangeContractMember us-gaap:FairValueMeasurementsRecurringMember 2019-12-31 0000028412 us-gaap:ForeignExchangeContractMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2019-12-31 0000028412 us-gaap:ForeignExchangeContractMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2019-12-31 0000028412 us-gaap:CommodityContractMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2019-12-31 0000028412 us-gaap:InterestRateContractMember us-gaap:FairValueMeasurementsRecurringMember 2019-12-31 0000028412 us-gaap:ForeignExchangeContractMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2019-12-31 0000028412 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:USTreasuryAndGovernmentMember 2019-12-31 0000028412 us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember cma:DeferredCompensationPlanAssetsMember 2019-12-31 0000028412 us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2019-12-31 0000028412 us-gaap:CommodityContractMember us-gaap:FairValueMeasurementsRecurringMember 2019-12-31 0000028412 us-gaap:InterestRateContractMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2019-12-31 0000028412 us-gaap:CommodityContractMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2019-12-31 0000028412 us-gaap:CommodityContractMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2019-12-31 0000028412 us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:USTreasuryAndGovernmentMember 2019-12-31 0000028412 us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember cma:DeferredCompensationPlanAssetsMember 2019-12-31 0000028412 us-gaap:InterestRateContractMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2019-12-31 0000028412 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:MortgageBackedSecuritiesMember 2019-12-31 0000028412 us-gaap:FairValueMeasurementsRecurringMember us-gaap:EquitySecuritiesMember 2019-12-31 0000028412 us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:USTreasuryAndGovernmentMember 2019-12-31 0000028412 us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:MortgageBackedSecuritiesMember 2019-12-31 0000028412 us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:EquitySecuritiesMember 2019-12-31 0000028412 us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:EquitySecuritiesMember 2019-12-31 0000028412 us-gaap:FairValueMeasurementsRecurringMember us-gaap:USTreasuryAndGovernmentMember 2019-12-31 0000028412 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:EquitySecuritiesMember 2019-12-31 0000028412 us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:MortgageBackedSecuritiesMember 2019-12-31 0000028412 us-gaap:InterestRateContractMember 2018-01-01 2018-12-31 0000028412 us-gaap:MunicipalBondsMember us-gaap:AvailableforsaleSecuritiesMember 2018-12-31 0000028412 us-gaap:EquitySecuritiesMember us-gaap:AvailableforsaleSecuritiesMember 2018-01-01 2018-12-31 0000028412 us-gaap:MunicipalBondsMember us-gaap:AvailableforsaleSecuritiesMember 2018-01-01 2018-12-31 0000028412 us-gaap:EquitySecuritiesMember us-gaap:EquitySecuritiesMember 2018-01-01 2018-12-31 0000028412 us-gaap:InterestRateContractMember 2019-01-01 2019-12-31 0000028412 us-gaap:InterestRateContractMember 2018-12-31 0000028412 us-gaap:EquitySecuritiesMember us-gaap:EquitySecuritiesMember 2018-01-01 0000028412 us-gaap:EquitySecuritiesMember us-gaap:AvailableforsaleSecuritiesMember 2018-12-31 0000028412 us-gaap:InterestRateContractMember 2017-12-31 0000028412 us-gaap:EquitySecuritiesMember us-gaap:AvailableforsaleSecuritiesMember 2018-01-01 0000028412 us-gaap:AvailableforsaleSecuritiesMember 2018-01-01 2018-12-31 0000028412 us-gaap:AvailableforsaleSecuritiesMember 2017-12-31 0000028412 us-gaap:InterestRateContractMember 2019-12-31 0000028412 us-gaap:EquitySecuritiesMember us-gaap:AvailableforsaleSecuritiesMember 2017-12-31 0000028412 us-gaap:MunicipalBondsMember us-gaap:AvailableforsaleSecuritiesMember 2017-12-31 0000028412 us-gaap:AvailableforsaleSecuritiesMember 2018-12-31 0000028412 us-gaap:AvailableforsaleSecuritiesMember 2018-01-01 0000028412 us-gaap:EstimateOfFairValueFairValueDisclosureMember 2018-12-31 0000028412 us-gaap:FairValueInputsLevel1Member us-gaap:EstimateOfFairValueFairValueDisclosureMember 2018-12-31 0000028412 us-gaap:CarryingReportedAmountFairValueDisclosureMember 2018-12-31 0000028412 us-gaap:FairValueInputsLevel2Member us-gaap:EstimateOfFairValueFairValueDisclosureMember 2019-12-31 0000028412 us-gaap:FairValueInputsLevel1Member us-gaap:EstimateOfFairValueFairValueDisclosureMember 2019-12-31 0000028412 us-gaap:FairValueInputsLevel3Member us-gaap:EstimateOfFairValueFairValueDisclosureMember 2019-12-31 0000028412 us-gaap:FairValueInputsLevel2Member us-gaap:EstimateOfFairValueFairValueDisclosureMember 2018-12-31 0000028412 us-gaap:FairValueInputsLevel3Member us-gaap:EstimateOfFairValueFairValueDisclosureMember 2018-12-31 0000028412 us-gaap:EstimateOfFairValueFairValueDisclosureMember 2019-12-31 0000028412 us-gaap:FairValueMeasurementsRecurringMember 2018-01-01 2018-12-31 0000028412 us-gaap:MortgageBackedSecuritiesMember us-gaap:PrepaymentRiskMember 2019-12-31 0000028412 us-gaap:USTreasuryAndGovernmentMember 2019-12-31 0000028412 us-gaap:MortgageBackedSecuritiesMember 2019-12-31 0000028412 us-gaap:MortgageBackedSecuritiesMember 2018-12-31 0000028412 us-gaap:USTreasuryAndGovernmentMember 2018-12-31 0000028412 us-gaap:DebtSecuritiesMember 2019-12-31 0000028412 us-gaap:ResidentialMortgageBackedSecuritiesMember 2019-12-31 0000028412 us-gaap:ResidentialMortgageBackedSecuritiesMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialAndIndustrialSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:GeographicDistributionDomesticMember us-gaap:PaymentDeferralMember 2018-01-01 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:GeographicDistributionDomesticMember us-gaap:ContractualInterestRateReductionMember 2019-01-01 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ContractualInterestRateReductionMember 2018-01-01 2018-12-31 0000028412 us-gaap:ContractualInterestRateReductionMember 2019-01-01 2019-12-31 0000028412 us-gaap:PaymentDeferralMember 2019-01-01 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialAndIndustrialSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:GeographicDistributionDomesticMember us-gaap:ContractualInterestRateReductionMember 2019-01-01 2019-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember us-gaap:HomeEquityLoanMember 2018-01-01 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:GeographicDistributionForeignMember us-gaap:PaymentDeferralMember 2019-01-01 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialAndIndustrialSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:GeographicDistributionDomesticMember 2019-01-01 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialAndIndustrialSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:GeographicDistributionDomesticMember us-gaap:PaymentDeferralMember 2019-01-01 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:GeographicDistributionDomesticMember 2019-01-01 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialAndIndustrialSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:GeographicDistributionDomesticMember 2018-01-01 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:GeographicDistributionDomesticMember us-gaap:PaymentDeferralMember 2018-01-01 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialAndIndustrialSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:GeographicDistributionForeignMember us-gaap:ContractualInterestRateReductionMember 2019-01-01 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ContractualInterestRateReductionMember 2019-01-01 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:PaymentDeferralMember 2018-01-01 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:GeographicDistributionForeignMember us-gaap:PaymentDeferralMember 2018-01-01 2018-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember us-gaap:HomeEquityLoanMember us-gaap:PaymentDeferralMember 2019-01-01 2019-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember us-gaap:HomeEquityLoanMember us-gaap:PaymentDeferralMember 2018-01-01 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember 2018-01-01 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialAndIndustrialSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:GeographicDistributionForeignMember 2018-01-01 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialAndIndustrialSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:GeographicDistributionForeignMember 2019-01-01 2019-12-31 0000028412 us-gaap:ContractualInterestRateReductionMember 2018-01-01 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:GeographicDistributionDomesticMember us-gaap:PaymentDeferralMember 2019-01-01 2019-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember us-gaap:HomeEquityLoanMember us-gaap:ContractualInterestRateReductionMember 2018-01-01 2018-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember us-gaap:HomeEquityLoanMember us-gaap:ContractualInterestRateReductionMember 2019-01-01 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialAndIndustrialSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:GeographicDistributionForeignMember us-gaap:ContractualInterestRateReductionMember 2018-01-01 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:GeographicDistributionDomesticMember us-gaap:ContractualInterestRateReductionMember 2018-01-01 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:PaymentDeferralMember 2019-01-01 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:GeographicDistributionDomesticMember 2018-01-01 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialAndIndustrialSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:GeographicDistributionDomesticMember us-gaap:ContractualInterestRateReductionMember 2018-01-01 2018-12-31 0000028412 us-gaap:PaymentDeferralMember 2018-01-01 2018-12-31 0000028412 us-gaap:ConsumerPortfolioSegmentMember us-gaap:ResidentialMortgageMember 2018-01-01 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:RealEstateSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:GeographicDistributionDomesticMember 2018-01-01 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:GeographicDistributionForeignMember 2017-01-01 2017-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember us-gaap:HomeEquityLoanMember 2017-01-01 2017-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:GeographicDistributionDomesticMember 2019-01-01 2019-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember 2019-01-01 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:RealEstateSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:GeographicDistributionDomesticMember 2019-01-01 2019-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember 2018-01-01 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:RealEstateSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:GeographicDistributionDomesticMember 2017-01-01 2017-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:GeographicDistributionForeignMember 2018-01-01 2018-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember cma:ConsumerFinancingReceivableMember 2018-01-01 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:GeographicDistributionDomesticMember 2017-01-01 2017-12-31 0000028412 us-gaap:ConsumerPortfolioSegmentMember 2017-01-01 2017-12-31 0000028412 us-gaap:ConsumerPortfolioSegmentMember 2018-01-01 2018-12-31 0000028412 us-gaap:ConsumerPortfolioSegmentMember us-gaap:ResidentialMortgageMember 2017-01-01 2017-12-31 0000028412 cma:BusinessLoansMember us-gaap:CommercialBorrowerMember us-gaap:FinanceLeasesPortfolioSegmentMember us-gaap:GeographicDistributionDomesticMember 2018-01-01 2018-12-31 0000028412 cma:BusinessLoansMember us-gaap:CommercialBorrowerMember us-gaap:FinanceLeasesPortfolioSegmentMember us-gaap:GeographicDistributionDomesticMember 2017-01-01 2017-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:GeographicDistributionDomesticMember 2018-01-01 2018-12-31 0000028412 us-gaap:ConsumerPortfolioSegmentMember us-gaap:ResidentialMortgageMember 2019-01-01 2019-12-31 0000028412 cma:BusinessLoansMember us-gaap:CommercialBorrowerMember us-gaap:FinanceLeasesPortfolioSegmentMember us-gaap:GeographicDistributionDomesticMember 2019-01-01 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember 2017-01-01 2017-12-31 0000028412 us-gaap:ConsumerPortfolioSegmentMember 2019-01-01 2019-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember cma:ConsumerFinancingReceivableMember 2017-01-01 2017-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember 2017-01-01 2017-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialAndIndustrialSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:GeographicDistributionDomesticMember 2017-01-01 2017-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:GeographicDistributionDomesticMember 2017-01-01 2017-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:GeographicDistributionForeignMember 2019-01-01 2019-12-31 0000028412 us-gaap:LoanOriginationCommitmentsMember 2019-01-01 2019-12-31 0000028412 us-gaap:LoanOriginationCommitmentsMember 2018-12-31 0000028412 us-gaap:LoanOriginationCommitmentsMember 2018-01-01 2018-12-31 0000028412 us-gaap:LoanOriginationCommitmentsMember 2016-12-31 0000028412 us-gaap:LoanOriginationCommitmentsMember 2017-12-31 0000028412 us-gaap:LoanOriginationCommitmentsMember 2019-12-31 0000028412 us-gaap:LoanOriginationCommitmentsMember 2017-01-01 2017-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:FinancingReceivablesEqualToGreaterThan90DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2019-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember us-gaap:HomeEquityLoanMember us-gaap:FinancingReceivables60To89DaysPastDueMember 2018-12-31 0000028412 us-gaap:ConsumerPortfolioSegmentMember us-gaap:ResidentialMortgageMember us-gaap:FinancingReceivablesEqualToGreaterThan90DaysPastDueMember 2018-12-31 0000028412 us-gaap:ConsumerPortfolioSegmentMember us-gaap:ResidentialMortgageMember us-gaap:FinancingReceivables60To89DaysPastDueMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:FinancingReceivables60To89DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:RealEstateSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:GeographicDistributionDomesticMember 2019-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember 2018-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember us-gaap:HomeEquityLoanMember us-gaap:FinancingReceivables30To59DaysPastDueMember 2019-12-31 0000028412 us-gaap:ConsumerPortfolioSegmentMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:RealEstateSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:FinancingReceivables60To89DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2018-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember us-gaap:HomeEquityLoanMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:RealEstateSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:GeographicDistributionDomesticMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:RealEstateSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:GeographicDistributionDomesticMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember cma:LeaseFinancingMember us-gaap:FinancingReceivables30To59DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:FinancingReceivablesEqualToGreaterThan90DaysPastDueMember us-gaap:GeographicDistributionForeignMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialAndIndustrialSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:GeographicDistributionDomesticMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember cma:LeaseFinancingMember us-gaap:GeographicDistributionDomesticMember 2019-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember cma:ConsumerFinancingReceivableMember us-gaap:FinancingReceivables60To89DaysPastDueMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:RealEstateSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:GeographicDistributionDomesticMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:FinancingReceivables60To89DaysPastDueMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:FinancingReceivablesEqualToGreaterThan90DaysPastDueMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:GeographicDistributionDomesticMember 2018-12-31 0000028412 us-gaap:ConsumerPortfolioSegmentMember us-gaap:FinancingReceivablesEqualToGreaterThan90DaysPastDueMember 2019-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember cma:ConsumerFinancingReceivableMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialAndIndustrialSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:FinancingReceivablesEqualToGreaterThan90DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:RealEstateSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:FinancingReceivablesEqualToGreaterThan90DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:FinancingReceivables30To59DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:RealEstateSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:FinancingReceivablesEqualToGreaterThan90DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:GeographicDistributionDomesticMember 2018-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember cma:ConsumerFinancingReceivableMember us-gaap:FinancingReceivables60To89DaysPastDueMember 2018-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember us-gaap:FinancingReceivables30To59DaysPastDueMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:RealEstateSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:FinancingReceivables60To89DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:GeographicDistributionForeignMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:FinancingReceivablesEqualToGreaterThan90DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:FinancingReceivables60To89DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2019-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember cma:ConsumerFinancingReceivableMember us-gaap:FinancingReceivablesEqualToGreaterThan90DaysPastDueMember 2019-12-31 0000028412 us-gaap:ConsumerPortfolioSegmentMember us-gaap:ResidentialMortgageMember 2018-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember us-gaap:FinancingReceivablesEqualToGreaterThan90DaysPastDueMember 2019-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember 2019-12-31 0000028412 us-gaap:ConsumerPortfolioSegmentMember us-gaap:ResidentialMortgageMember us-gaap:FinancingReceivables30To59DaysPastDueMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialAndIndustrialSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:FinancingReceivablesEqualToGreaterThan90DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:FinancingReceivables30To59DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialAndIndustrialSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:GeographicDistributionDomesticMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:GeographicDistributionForeignMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember cma:LeaseFinancingMember us-gaap:FinancingReceivables60To89DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2019-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember cma:ConsumerFinancingReceivableMember us-gaap:FinancingReceivables30To59DaysPastDueMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:FinancingReceivablesEqualToGreaterThan90DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialAndIndustrialSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:FinancingReceivablesEqualToGreaterThan90DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2018-12-31 0000028412 us-gaap:ConsumerPortfolioSegmentMember us-gaap:ResidentialMortgageMember us-gaap:FinancingReceivables60To89DaysPastDueMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialAndIndustrialSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:FinancingReceivables60To89DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:GeographicDistributionDomesticMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialAndIndustrialSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:FinancingReceivables60To89DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialAndIndustrialSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:GeographicDistributionDomesticMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:GeographicDistributionDomesticMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:FinancingReceivablesEqualToGreaterThan90DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:FinancingReceivablesEqualToGreaterThan90DaysPastDueMember us-gaap:GeographicDistributionForeignMember 2019-12-31 0000028412 us-gaap:ConsumerPortfolioSegmentMember us-gaap:ResidentialMortgageMember 2019-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember us-gaap:FinancingReceivablesEqualToGreaterThan90DaysPastDueMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:FinancingReceivables30To59DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:FinancingReceivables30To59DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2018-12-31 0000028412 us-gaap:ConsumerPortfolioSegmentMember us-gaap:FinancingReceivables30To59DaysPastDueMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember cma:LeaseFinancingMember us-gaap:FinancingReceivablesEqualToGreaterThan90DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:RealEstateSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:FinancingReceivablesEqualToGreaterThan90DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember cma:LeaseFinancingMember us-gaap:GeographicDistributionDomesticMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:FinancingReceivables30To59DaysPastDueMember us-gaap:GeographicDistributionForeignMember 2018-12-31 0000028412 us-gaap:FinancingReceivablesEqualToGreaterThan90DaysPastDueMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:RealEstateSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:FinancingReceivablesEqualToGreaterThan90DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:FinancingReceivables30To59DaysPastDueMember 2018-12-31 0000028412 us-gaap:ConsumerPortfolioSegmentMember us-gaap:ResidentialMortgageMember us-gaap:FinancingReceivablesEqualToGreaterThan90DaysPastDueMember 2019-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember us-gaap:FinancingReceivables60To89DaysPastDueMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialAndIndustrialSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:FinancingReceivables30To59DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:FinancingReceivables30To59DaysPastDueMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember cma:LeaseFinancingMember us-gaap:FinancingReceivables30To59DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialAndIndustrialSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:FinancingReceivables30To59DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:GeographicDistributionDomesticMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:RealEstateSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:FinancingReceivables30To59DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2019-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember us-gaap:HomeEquityLoanMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:FinancingReceivables60To89DaysPastDueMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialAndIndustrialSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:FinancingReceivablesEqualToGreaterThan90DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:FinancingReceivablesEqualToGreaterThan90DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2018-12-31 0000028412 us-gaap:ConsumerPortfolioSegmentMember us-gaap:ResidentialMortgageMember us-gaap:FinancingReceivables30To59DaysPastDueMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialAndIndustrialSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:FinancingReceivables30To59DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember cma:LeaseFinancingMember us-gaap:FinancingReceivables60To89DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:FinancingReceivablesEqualToGreaterThan90DaysPastDueMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:RealEstateSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:FinancingReceivables60To89DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2019-12-31 0000028412 us-gaap:ConsumerPortfolioSegmentMember 2018-12-31 0000028412 us-gaap:ConsumerPortfolioSegmentMember us-gaap:FinancingReceivables30To59DaysPastDueMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialAndIndustrialSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:FinancingReceivables60To89DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2018-12-31 0000028412 us-gaap:ConsumerPortfolioSegmentMember us-gaap:FinancingReceivablesEqualToGreaterThan90DaysPastDueMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember cma:LeaseFinancingMember us-gaap:FinancingReceivablesEqualToGreaterThan90DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:RealEstateSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:FinancingReceivables30To59DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:RealEstateSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:FinancingReceivables30To59DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:FinancingReceivables60To89DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:FinancingReceivables30To59DaysPastDueMember us-gaap:GeographicDistributionForeignMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:FinancingReceivables60To89DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:FinancingReceivables30To59DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:FinancingReceivables60To89DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialAndIndustrialSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:FinancingReceivables60To89DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2018-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember us-gaap:HomeEquityLoanMember us-gaap:FinancingReceivablesEqualToGreaterThan90DaysPastDueMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:FinancingReceivablesEqualToGreaterThan90DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:FinancingReceivables60To89DaysPastDueMember us-gaap:GeographicDistributionForeignMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialAndIndustrialSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:GeographicDistributionDomesticMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialAndIndustrialSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:FinancingReceivables30To59DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:GeographicDistributionDomesticMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:RealEstateSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:FinancingReceivables30To59DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2018-12-31 0000028412 us-gaap:FinancingReceivablesEqualToGreaterThan90DaysPastDueMember 2018-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember us-gaap:HomeEquityLoanMember us-gaap:FinancingReceivables30To59DaysPastDueMember 2018-12-31 0000028412 us-gaap:ConsumerPortfolioSegmentMember us-gaap:FinancingReceivables60To89DaysPastDueMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:RealEstateSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:FinancingReceivables60To89DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:FinancingReceivables30To59DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2018-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember cma:ConsumerFinancingReceivableMember us-gaap:FinancingReceivables30To59DaysPastDueMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:FinancingReceivables60To89DaysPastDueMember us-gaap:GeographicDistributionDomesticMember 2019-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember us-gaap:FinancingReceivables30To59DaysPastDueMember 2019-12-31 0000028412 us-gaap:FinancingReceivables60To89DaysPastDueMember 2018-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember us-gaap:HomeEquityLoanMember us-gaap:FinancingReceivables60To89DaysPastDueMember 2019-12-31 0000028412 us-gaap:FinancingReceivables30To59DaysPastDueMember 2019-12-31 0000028412 us-gaap:ConsumerPortfolioSegmentMember us-gaap:FinancingReceivables60To89DaysPastDueMember 2019-12-31 0000028412 us-gaap:FinancingReceivables60To89DaysPastDueMember 2019-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember us-gaap:FinancingReceivables60To89DaysPastDueMember 2019-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember us-gaap:HomeEquityLoanMember us-gaap:FinancingReceivablesEqualToGreaterThan90DaysPastDueMember 2019-12-31 0000028412 us-gaap:FinancingReceivables30To59DaysPastDueMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:FinancingReceivables60To89DaysPastDueMember us-gaap:GeographicDistributionForeignMember 2019-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember cma:ConsumerFinancingReceivableMember us-gaap:FinancingReceivablesEqualToGreaterThan90DaysPastDueMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember cma:LeaseFinancingMember us-gaap:GeographicDistributionDomesticMember us-gaap:DoubtfulMember 2019-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember us-gaap:HomeEquityLoanMember us-gaap:PassMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialAndIndustrialSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:GeographicDistributionDomesticMember us-gaap:SpecialMentionMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:RealEstateSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:GeographicDistributionDomesticMember us-gaap:DoubtfulMember 2019-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember us-gaap:PassMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:GeographicDistributionDomesticMember us-gaap:PassMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:RealEstateSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:GeographicDistributionDomesticMember us-gaap:SpecialMentionMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:GeographicDistributionDomesticMember us-gaap:SpecialMentionMember 2019-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember us-gaap:SpecialMentionMember 2019-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember cma:ConsumerFinancingReceivableMember us-gaap:SpecialMentionMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:GeographicDistributionForeignMember us-gaap:SubstandardMember 2019-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember us-gaap:PassMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:RealEstateSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:GeographicDistributionDomesticMember us-gaap:PassMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialAndIndustrialSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:GeographicDistributionDomesticMember us-gaap:PassMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialAndIndustrialSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:GeographicDistributionDomesticMember us-gaap:SubstandardMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:GeographicDistributionDomesticMember us-gaap:SubstandardMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:RealEstateSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:GeographicDistributionDomesticMember us-gaap:PassMember 2018-12-31 0000028412 us-gaap:ConsumerPortfolioSegmentMember us-gaap:PassMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:RealEstateSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:GeographicDistributionDomesticMember us-gaap:SpecialMentionMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:GeographicDistributionForeignMember us-gaap:PassMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:RealEstateSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:GeographicDistributionDomesticMember us-gaap:SubstandardMember 2019-12-31 0000028412 us-gaap:ConsumerPortfolioSegmentMember us-gaap:ResidentialMortgageMember us-gaap:PassMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:GeographicDistributionDomesticMember us-gaap:SubstandardMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:GeographicDistributionDomesticMember us-gaap:SubstandardMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialAndIndustrialSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:GeographicDistributionDomesticMember us-gaap:PassMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:RealEstateSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:GeographicDistributionDomesticMember us-gaap:DoubtfulMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialAndIndustrialSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:GeographicDistributionDomesticMember us-gaap:DoubtfulMember 2018-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember us-gaap:SpecialMentionMember 2018-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember us-gaap:HomeEquityLoanMember us-gaap:SubstandardMember 2018-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember us-gaap:HomeEquityLoanMember us-gaap:SpecialMentionMember 2019-12-31 0000028412 us-gaap:SubstandardMember 2019-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember us-gaap:DoubtfulMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialAndIndustrialSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:GeographicDistributionDomesticMember us-gaap:DoubtfulMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialAndIndustrialSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:GeographicDistributionDomesticMember us-gaap:SubstandardMember 2019-12-31 0000028412 us-gaap:SpecialMentionMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:GeographicDistributionDomesticMember us-gaap:DoubtfulMember 2018-12-31 0000028412 us-gaap:DoubtfulMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:RealEstateSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:GeographicDistributionDomesticMember us-gaap:DoubtfulMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:GeographicDistributionDomesticMember us-gaap:PassMember 2019-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember cma:ConsumerFinancingReceivableMember us-gaap:SpecialMentionMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:RealEstateSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:GeographicDistributionDomesticMember us-gaap:DoubtfulMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:GeographicDistributionDomesticMember us-gaap:DoubtfulMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember cma:LeaseFinancingMember us-gaap:GeographicDistributionDomesticMember us-gaap:SpecialMentionMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialAndIndustrialSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:GeographicDistributionDomesticMember us-gaap:DoubtfulMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:DoubtfulMember 2019-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember cma:ConsumerFinancingReceivableMember us-gaap:DoubtfulMember 2018-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember us-gaap:HomeEquityLoanMember us-gaap:DoubtfulMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:GeographicDistributionDomesticMember us-gaap:DoubtfulMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:SubstandardMember 2019-12-31 0000028412 us-gaap:ConsumerPortfolioSegmentMember us-gaap:ResidentialMortgageMember us-gaap:SpecialMentionMember 2018-12-31 0000028412 us-gaap:ConsumerPortfolioSegmentMember us-gaap:SubstandardMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialAndIndustrialSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:GeographicDistributionDomesticMember us-gaap:SpecialMentionMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:GeographicDistributionDomesticMember us-gaap:DoubtfulMember 2018-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember us-gaap:HomeEquityLoanMember us-gaap:PassMember 2019-12-31 0000028412 us-gaap:ConsumerPortfolioSegmentMember us-gaap:DoubtfulMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember cma:LeaseFinancingMember us-gaap:GeographicDistributionDomesticMember us-gaap:SubstandardMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember cma:LeaseFinancingMember us-gaap:GeographicDistributionDomesticMember us-gaap:SubstandardMember 2018-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember us-gaap:SubstandardMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:GeographicDistributionDomesticMember us-gaap:SpecialMentionMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:GeographicDistributionForeignMember us-gaap:DoubtfulMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:GeographicDistributionForeignMember us-gaap:PassMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:RealEstateSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:GeographicDistributionDomesticMember us-gaap:PassMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:GeographicDistributionForeignMember us-gaap:SpecialMentionMember 2019-12-31 0000028412 us-gaap:PassMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:RealEstateSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:GeographicDistributionDomesticMember us-gaap:SubstandardMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:SpecialMentionMember 2019-12-31 0000028412 us-gaap:ConsumerPortfolioSegmentMember us-gaap:SubstandardMember 2019-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember cma:ConsumerFinancingReceivableMember us-gaap:SubstandardMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialAndIndustrialSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:GeographicDistributionDomesticMember us-gaap:SubstandardMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:RealEstateSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:GeographicDistributionDomesticMember us-gaap:SpecialMentionMember 2018-12-31 0000028412 us-gaap:DoubtfulMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:GeographicDistributionDomesticMember us-gaap:SpecialMentionMember 2019-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember us-gaap:HomeEquityLoanMember us-gaap:SubstandardMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialAndIndustrialSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:GeographicDistributionDomesticMember us-gaap:SpecialMentionMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember cma:LeaseFinancingMember us-gaap:GeographicDistributionDomesticMember us-gaap:SpecialMentionMember 2018-12-31 0000028412 us-gaap:PassMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:SpecialMentionMember 2018-12-31 0000028412 us-gaap:ConsumerPortfolioSegmentMember us-gaap:ResidentialMortgageMember us-gaap:SubstandardMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:RealEstateSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:GeographicDistributionDomesticMember us-gaap:SubstandardMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:GeographicDistributionDomesticMember us-gaap:PassMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:GeographicDistributionForeignMember us-gaap:SpecialMentionMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:PassMember 2019-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember us-gaap:SubstandardMember 2018-12-31 0000028412 us-gaap:ConsumerPortfolioSegmentMember us-gaap:DoubtfulMember 2019-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember cma:ConsumerFinancingReceivableMember us-gaap:PassMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:GeographicDistributionDomesticMember us-gaap:DoubtfulMember 2018-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember cma:ConsumerFinancingReceivableMember us-gaap:DoubtfulMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:GeographicDistributionForeignMember us-gaap:DoubtfulMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:GeographicDistributionDomesticMember us-gaap:SpecialMentionMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:GeographicDistributionDomesticMember us-gaap:SubstandardMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:RealEstateSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:GeographicDistributionDomesticMember us-gaap:SubstandardMember 2019-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember us-gaap:HomeEquityLoanMember us-gaap:DoubtfulMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:PassMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialAndIndustrialSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:GeographicDistributionDomesticMember us-gaap:SubstandardMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:GeographicDistributionForeignMember us-gaap:SubstandardMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialAndIndustrialSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:GeographicDistributionDomesticMember us-gaap:PassMember 2019-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember cma:ConsumerFinancingReceivableMember us-gaap:PassMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:GeographicDistributionDomesticMember us-gaap:PassMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:GeographicDistributionDomesticMember us-gaap:DoubtfulMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialAndIndustrialSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:GeographicDistributionDomesticMember us-gaap:DoubtfulMember 2019-12-31 0000028412 us-gaap:SubstandardMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:DoubtfulMember 2018-12-31 0000028412 us-gaap:ConsumerPortfolioSegmentMember us-gaap:ResidentialMortgageMember us-gaap:PassMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:GeographicDistributionDomesticMember us-gaap:PassMember 2019-12-31 0000028412 us-gaap:SpecialMentionMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:GeographicDistributionDomesticMember us-gaap:SubstandardMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:RealEstateSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:GeographicDistributionDomesticMember us-gaap:PassMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember cma:LeaseFinancingMember us-gaap:GeographicDistributionDomesticMember us-gaap:DoubtfulMember 2018-12-31 0000028412 us-gaap:ConsumerPortfolioSegmentMember us-gaap:SpecialMentionMember 2019-12-31 0000028412 us-gaap:ConsumerPortfolioSegmentMember us-gaap:ResidentialMortgageMember us-gaap:DoubtfulMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:GeographicDistributionDomesticMember us-gaap:SpecialMentionMember 2018-12-31 0000028412 us-gaap:ConsumerPortfolioSegmentMember us-gaap:ResidentialMortgageMember us-gaap:SubstandardMember 2019-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember us-gaap:DoubtfulMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember cma:LeaseFinancingMember us-gaap:GeographicDistributionDomesticMember us-gaap:PassMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:RealEstateSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:GeographicDistributionDomesticMember us-gaap:SpecialMentionMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialAndIndustrialSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:GeographicDistributionDomesticMember us-gaap:PassMember 2018-12-31 0000028412 us-gaap:ConsumerPortfolioSegmentMember us-gaap:ResidentialMortgageMember us-gaap:SpecialMentionMember 2019-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember cma:ConsumerFinancingReceivableMember us-gaap:SubstandardMember 2019-12-31 0000028412 us-gaap:ConsumerPortfolioSegmentMember us-gaap:ResidentialMortgageMember us-gaap:DoubtfulMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:GeographicDistributionDomesticMember us-gaap:PassMember 2019-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialAndIndustrialSectorMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:GeographicDistributionDomesticMember us-gaap:SpecialMentionMember 2018-12-31 0000028412 us-gaap:ConsumerPortfolioSegmentMember us-gaap:PassMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:ConstructionLoansMember us-gaap:GeographicDistributionDomesticMember us-gaap:SpecialMentionMember 2019-12-31 0000028412 us-gaap:ConsumerBorrowerMember us-gaap:ConsumerPortfolioSegmentMember us-gaap:HomeEquityLoanMember us-gaap:SpecialMentionMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember cma:LeaseFinancingMember us-gaap:GeographicDistributionDomesticMember us-gaap:PassMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:SubstandardMember 2018-12-31 0000028412 us-gaap:ConsumerPortfolioSegmentMember us-gaap:SpecialMentionMember 2018-12-31 0000028412 us-gaap:CommercialBorrowerMember us-gaap:CommercialPortfolioSegmentMember us-gaap:RealEstateLoanMember us-gaap:GeographicDistributionDomesticMember us-gaap:SubstandardMember 2019-12-31 0000028412 us-gaap:FinanceReceivablesMember us-gaap:CommercialPortfolioSegmentMember 2017-12-31 0000028412 us-gaap:FinanceReceivablesMember us-gaap:ConsumerPortfolioSegmentMember 2019-12-31 0000028412 us-gaap:FinanceReceivablesMember us-gaap:CommercialPortfolioSegmentMember 2018-01-01 2018-12-31 0000028412 us-gaap:FinanceReceivablesMember us-gaap:CommercialPortfolioSegmentMember 2019-12-31 0000028412 us-gaap:FinanceReceivablesMember 2019-12-31 0000028412 us-gaap:FinanceReceivablesMember us-gaap:CommercialPortfolioSegmentMember 2018-12-31 0000028412 us-gaap:FinanceReceivablesMember us-gaap:ConsumerPortfolioSegmentMember 2018-01-01 2018-12-31 0000028412 us-gaap:FinanceReceivablesMember 2017-12-31 0000028412 us-gaap:FinanceReceivablesMember 2018-01-01 2018-12-31 0000028412 us-gaap:FinanceReceivablesMember us-gaap:ConsumerPortfolioSegmentMember 2017-12-31 0000028412 us-gaap:FinanceReceivablesMember 2016-12-31 0000028412 us-gaap:FinanceReceivablesMember 2019-01-01 2019-12-31 0000028412 us-gaap:FinanceReceivablesMember 2018-12-31 0000028412 us-gaap:FinanceReceivablesMember 2017-01-01 2017-12-31 0000028412 us-gaap:FinanceReceivablesMember us-gaap:CommercialPortfolioSegmentMember 2017-01-01 2017-12-31 0000028412 us-gaap:FinanceReceivablesMember us-gaap:ConsumerPortfolioSegmentMember 2018-12-31 0000028412 us-gaap:FinanceReceivablesMember us-gaap:CommercialPortfolioSegmentMember 2019-01-01 2019-12-31 0000028412 us-gaap:FinanceReceivablesMember us-gaap:ConsumerPortfolioSegmentMember 2017-01-01 2017-12-31 0000028412 us-gaap:FinanceReceivablesMember us-gaap:ConsumerPortfolioSegmentMember 2019-01-01 2019-12-31 0000028412 us-gaap:FinanceReceivablesMember us-gaap:CommercialPortfolioSegmentMember 2016-12-31 0000028412 us-gaap:FinanceReceivablesMember us-gaap:ConsumerPortfolioSegmentMember 2016-12-31 0000028412 cma:AbNoteRestructuresMember 2018-01-01 2018-12-31 0000028412 cma:AbNoteRestructuresMember 2019-01-01 2019-12-31 0000028412 us-gaap:CommercialPortfolioSegmentMember 2019-12-31 0000028412 cma:AutomotiveProductionMember 2019-12-31 0000028412 cma:AutomotiveProductionMember 2018-12-31 0000028412 cma:AutomotiveDealerMember 2018-12-31 0000028412 cma:AutomotiveDealerMember 2019-12-31 0000028412 us-gaap:RealEstateLoanMember 2018-12-31 0000028412 us-gaap:CommercialRealEstateMember 2018-12-31 0000028412 cma:CommercialRealEstateBusinessLineMember us-gaap:ConstructionLoansMember 2018-12-31 0000028412 cma:CommercialRealEstateBusinessLineMember us-gaap:RealEstateLoanMember 2018-12-31 0000028412 us-gaap:CommercialRealEstateMember 2019-12-31 0000028412 us-gaap:ConstructionLoansMember 2019-12-31 0000028412 us-gaap:ConstructionLoansMember 2018-12-31 0000028412 cma:OtherBusinessLinesMember us-gaap:RealEstateLoanMember 2019-12-31 0000028412 cma:CommercialRealEstateBusinessLineMember us-gaap:RealEstateLoanMember 2019-12-31 0000028412 cma:OtherBusinessLinesMember us-gaap:RealEstateLoanMember 2018-12-31 0000028412 cma:CommercialRealEstateBusinessLineMember us-gaap:ConstructionLoansMember 2019-12-31 0000028412 us-gaap:RealEstateLoanMember 2019-12-31 0000028412 cma:OtherBusinessLinesMember us-gaap:ConstructionLoansMember 2019-12-31 0000028412 cma:OtherBusinessLinesMember us-gaap:ConstructionLoansMember 2018-12-31 0000028412 us-gaap:CoreDepositsMember 2019-12-31 0000028412 cma:WealthManagementMember 2018-12-31 0000028412 cma:RetailBankMember 2018-12-31 0000028412 cma:BusinessBankMember 2019-12-31 0000028412 cma:WealthManagementMember 2019-12-31 0000028412 cma:BusinessBankMember 2018-12-31 0000028412 cma:RetailBankMember 2019-12-31 0000028412 us-gaap:CoreDepositsMember 2019-01-01 2019-12-31 0000028412 us-gaap:CoreDepositsMember 2018-12-31 0000028412 us-gaap:CoreDepositsMember 2018-01-01 2018-12-31 0000028412 cma:CommercialAndOtherMember srt:MaximumMember us-gaap:CommitmentsToExtendCreditMember 2018-12-31 0000028412 srt:MaximumMember us-gaap:CommitmentsToExtendCreditMember 2018-12-31 0000028412 cma:BankcardHomeEquityAndOtherMember srt:MaximumMember us-gaap:CommitmentsToExtendCreditMember 2019-12-31 0000028412 srt:MaximumMember us-gaap:CommitmentsToExtendCreditMember 2019-12-31 0000028412 us-gaap:LetterOfCreditMember srt:MaximumMember 2018-12-31 0000028412 us-gaap:StandbyLettersOfCreditMember srt:MaximumMember 2018-12-31 0000028412 cma:BankcardHomeEquityAndOtherMember srt:MaximumMember us-gaap:CommitmentsToExtendCreditMember 2018-12-31 0000028412 us-gaap:StandbyLettersOfCreditMember srt:MaximumMember 2019-12-31 0000028412 us-gaap:LetterOfCreditMember srt:MaximumMember 2019-12-31 0000028412 cma:CommercialAndOtherMember srt:MaximumMember us-gaap:CommitmentsToExtendCreditMember 2019-12-31 0000028412 cma:RiskManagementDerivativesMember 2018-12-31 0000028412 cma:CustomerInitiatedAndOtherActivitiesDerivativesMember cma:InterestRateCapsAndFloorsPurchasedMember 2018-12-31 0000028412 cma:CustomerInitiatedAndOtherActivitiesDerivativesMember us-gaap:InterestRateContractMember 2018-12-31 0000028412 cma:RiskManagementDerivativesMember us-gaap:InterestRateSwapMember us-gaap:CashFlowHedgingMember us-gaap:DesignatedAsHedgingInstrumentMember 2018-12-31 0000028412 cma:RiskManagementDerivativesMember cma:ForeignExchangeSpotForwardAndSwapsMember us-gaap:NondesignatedMember 2018-12-31 0000028412 cma:RiskManagementDerivativesMember us-gaap:InterestRateSwapMember us-gaap:FairValueHedgingMember us-gaap:DesignatedAsHedgingInstrumentMember 2019-12-31 0000028412 cma:CustomerInitiatedAndOtherActivitiesDerivativesMember cma:EnergyCapsAndFloorsPurchasedMember 2019-12-31 0000028412 cma:CustomerInitiatedAndOtherActivitiesDerivativesMember cma:EnergyCapsAndFloorsPurchasedMember 2018-12-31 0000028412 cma:CustomerInitiatedAndOtherActivitiesDerivativesMember us-gaap:InterestRateContractMember 2019-12-31 0000028412 cma:CustomerInitiatedAndOtherActivitiesDerivativesMember 2019-12-31 0000028412 cma:CustomerInitiatedAndOtherActivitiesDerivativesMember us-gaap:CommodityContractMember 2018-12-31 0000028412 cma:CustomerInitiatedAndOtherActivitiesDerivativesMember cma:EnergyCapsAndFloorsWrittenMember 2019-12-31 0000028412 cma:CustomerInitiatedAndOtherActivitiesDerivativesMember us-gaap:InterestRateSwapMember 2019-12-31 0000028412 cma:CustomerInitiatedAndOtherActivitiesDerivativesMember cma:InterestRateCapsAndFloorsPurchasedMember 2019-12-31 0000028412 cma:RiskManagementDerivativesMember cma:ForeignExchangeSpotForwardAndSwapsMember us-gaap:NondesignatedMember 2019-12-31 0000028412 cma:CustomerInitiatedAndOtherActivitiesDerivativesMember us-gaap:CommodityContractMember 2019-12-31 0000028412 cma:CustomerInitiatedAndOtherActivitiesDerivativesMember cma:InterestRateCapsAndFloorsWrittenMember 2019-12-31 0000028412 cma:CustomerInitiatedAndOtherActivitiesDerivativesMember cma:ForeignExchangeSpotForwardsOptionsAndSwapsMember 2019-12-31 0000028412 cma:CustomerInitiatedAndOtherActivitiesDerivativesMember cma:InterestRateCapsAndFloorsWrittenMember 2018-12-31 0000028412 cma:RiskManagementDerivativesMember us-gaap:InterestRateSwapMember us-gaap:CashFlowHedgingMember us-gaap:DesignatedAsHedgingInstrumentMember 2019-12-31 0000028412 cma:CustomerInitiatedAndOtherActivitiesDerivativesMember cma:ForeignExchangeSpotForwardsOptionsAndSwapsMember 2018-12-31 0000028412 cma:CustomerInitiatedAndOtherActivitiesDerivativesMember cma:EnergySwapsMember 2018-12-31 0000028412 cma:CustomerInitiatedAndOtherActivitiesDerivativesMember cma:EnergyCapsAndFloorsWrittenMember 2018-12-31 0000028412 cma:RiskManagementDerivativesMember us-gaap:InterestRateSwapMember us-gaap:FairValueHedgingMember us-gaap:DesignatedAsHedgingInstrumentMember 2018-12-31 0000028412 cma:CustomerInitiatedAndOtherActivitiesDerivativesMember cma:EnergySwapsMember 2019-12-31 0000028412 cma:CustomerInitiatedAndOtherActivitiesDerivativesMember us-gaap:InterestRateSwapMember 2018-12-31 0000028412 cma:RiskManagementDerivativesMember 2019-12-31 0000028412 cma:CustomerInitiatedAndOtherActivitiesDerivativesMember 2018-12-31 0000028412 cma:RiskManagementDerivativesMember us-gaap:InterestRateSwapMember us-gaap:FairValueHedgingMember 2019-01-01 2019-12-31 0000028412 cma:RiskManagementDerivativesMember us-gaap:InterestRateSwapMember us-gaap:FairValueHedgingMember 2018-01-01 2018-12-31 0000028412 cma:RiskManagementDerivativesMember us-gaap:LongTermDebtMember us-gaap:InterestRateSwapMember us-gaap:FairValueHedgingMember 2019-12-31 0000028412 cma:RiskManagementDerivativesMember us-gaap:LongTermDebtMember us-gaap:InterestRateSwapMember us-gaap:FairValueHedgingMember 2018-12-31 0000028412 cma:RiskManagementDerivativesMember us-gaap:LoansMember us-gaap:SwapMember us-gaap:CashFlowHedgingMember 2019-12-31 0000028412 cma:CustomerInitiatedAndOtherActivitiesDerivativesMember us-gaap:ForeignExchangeContractMember us-gaap:ForeignCurrencyGainLossMember 2019-01-01 2019-12-31 0000028412 cma:CustomerInitiatedAndOtherActivitiesDerivativesMember us-gaap:ForeignExchangeContractMember us-gaap:ForeignCurrencyGainLossMember 2018-01-01 2018-12-31 0000028412 cma:CustomerInitiatedAndOtherActivitiesDerivativesMember 2019-01-01 2019-12-31 0000028412 cma:CustomerInitiatedAndOtherActivitiesDerivativesMember 2018-01-01 2018-12-31 0000028412 cma:CustomerInitiatedAndOtherActivitiesDerivativesMember us-gaap:CommodityContractMember us-gaap:OtherIncomeMember 2018-01-01 2018-12-31 0000028412 cma:CustomerInitiatedAndOtherActivitiesDerivativesMember us-gaap:InterestRateContractMember us-gaap:OtherIncomeMember 2018-01-01 2018-12-31 0000028412 cma:CustomerInitiatedAndOtherActivitiesDerivativesMember us-gaap:InterestRateContractMember us-gaap:OtherIncomeMember 2019-01-01 2019-12-31 0000028412 cma:CustomerInitiatedAndOtherActivitiesDerivativesMember us-gaap:CommodityContractMember us-gaap:OtherIncomeMember 2019-01-01 2019-12-31 0000028412 cma:RiskManagementDerivativesMember us-gaap:LongTermDebtMember us-gaap:InterestRateSwapMember us-gaap:FairValueHedgingMember 2018-01-01 2018-12-31 0000028412 cma:RiskManagementDerivativesMember us-gaap:LongTermDebtMember us-gaap:InterestRateSwapMember us-gaap:FairValueHedgingMember 2019-01-01 2019-12-31 0000028412 cma:RiskManagementDerivativesMember us-gaap:LoansMember us-gaap:SwapMember us-gaap:CashFlowHedgingMember 2019-01-01 2019-12-31 0000028412 us-gaap:VariableInterestEntityNotPrimaryBeneficiaryMember 2017-01-01 2017-12-31 0000028412 cma:LowIncomeHousingTaxCreditsMember us-gaap:VariableInterestEntityNotPrimaryBeneficiaryMember 2019-01-01 2019-12-31 0000028412 cma:OtherTaxBenefitsRelatedToTaxCreditEntitiesMember us-gaap:VariableInterestEntityNotPrimaryBeneficiaryMember 2019-01-01 2019-12-31 0000028412 cma:OtherTaxBenefitsRelatedToTaxCreditEntitiesMember us-gaap:VariableInterestEntityNotPrimaryBeneficiaryMember 2018-01-01 2018-12-31 0000028412 us-gaap:VariableInterestEntityNotPrimaryBeneficiaryMember 2019-01-01 2019-12-31 0000028412 us-gaap:VariableInterestEntityNotPrimaryBeneficiaryMember 2018-01-01 2018-12-31 0000028412 cma:LowIncomeHousingTaxCreditsMember us-gaap:VariableInterestEntityNotPrimaryBeneficiaryMember 2018-01-01 2018-12-31 0000028412 cma:LowIncomeHousingTaxCreditsMember us-gaap:VariableInterestEntityNotPrimaryBeneficiaryMember 2017-01-01 2017-12-31 0000028412 cma:OtherTaxBenefitsRelatedToTaxCreditEntitiesMember us-gaap:VariableInterestEntityNotPrimaryBeneficiaryMember 2017-01-01 2017-12-31 0000028412 cma:LowIncomeHousingTaxCreditEntitiesMember 2019-12-31 0000028412 cma:OtherTaxCreditEntitiesMember 2019-12-31 0000028412 cma:DomesticCertificatesOfDepositAndOtherDepositsMember 2018-12-31 0000028412 cma:DomesticCertificatesOfDepositAndOtherDepositsMember 2019-12-31 0000028412 us-gaap:FederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchaseMember 2017-01-01 2017-12-31 0000028412 us-gaap:BorrowingsMember 2018-01-01 2018-12-31 0000028412 us-gaap:FederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchaseMember 2017-12-31 0000028412 us-gaap:BorrowingsMember 2017-12-31 0000028412 us-gaap:FederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchaseMember 2019-12-31 0000028412 us-gaap:BorrowingsMember 2017-01-01 2017-12-31 0000028412 us-gaap:FederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchaseMember 2018-12-31 0000028412 us-gaap:FederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchaseMember 2019-01-01 2019-12-31 0000028412 us-gaap:BorrowingsMember 2019-01-01 2019-12-31 0000028412 us-gaap:BorrowingsMember 2019-12-31 0000028412 us-gaap:BorrowingsMember 2018-12-31 0000028412 us-gaap:FederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchaseMember 2018-01-01 2018-12-31 0000028412 srt:ParentCompanyMember cma:A4.00NotesDue2029Member 2019-08-01 0000028412 srt:SubsidiariesMember cma:TwoPointFivePercentageNotesDue2024MemberDomain 2019-07-23 0000028412 srt:ParentCompanyMember cma:A4.00NotesDue2029Member 2019-02-01 0000028412 srt:SubsidiariesMember 2019-12-31 0000028412 srt:SubsidiariesMember 2018-12-31 0000028412 srt:ParentCompanyMember cma:ThreePointEightZeroPercentSubNotesDue2026Member 2019-12-31 0000028412 srt:ParentCompanyMember cma:TwoPointOneTwoFivePercentageNotesDue2019MemberDomain 2019-12-31 0000028412 srt:ParentCompanyMember 2019-12-31 0000028412 srt:SubsidiariesMember cma:FloatingRateBasedonFHLBAuctionDue2026Member 2019-12-31 0000028412 srt:SubsidiariesMember cma:FloatingratebasedonFHLBauctionratedue2028Member 2019-12-31 0000028412 srt:ParentCompanyMember cma:TwoPointOneTwoFivePercentageNotesDue2019MemberDomain 2018-12-31 0000028412 srt:SubsidiariesMember cma:TwoPointFivePercentageNotesDue2020MemberDomainDomain 2019-12-31 0000028412 srt:SubsidiariesMember cma:FourPercentSubordinatedNotesDue2025Member 2018-12-31 0000028412 srt:SubsidiariesMember cma:TwoPointFivePercentageNotesDue2024MemberDomain 2019-12-31 0000028412 srt:SubsidiariesMember cma:FloatingRateBasedonFHLBAuctionDue2026Member 2018-12-31 0000028412 srt:ParentCompanyMember cma:A4.00NotesDue2029Member 2019-12-31 0000028412 srt:ParentCompanyMember cma:A4.00NotesDue2029Member 2018-12-31 0000028412 srt:ParentCompanyMember 2018-12-31 0000028412 srt:SubsidiariesMember cma:SevenPointEightSevenFivePercentageSubordinatedNoteDue2026Member 2019-12-31 0000028412 srt:SubsidiariesMember cma:TwoPointFivePercentageNotesDue2020MemberDomainDomain 2018-12-31 0000028412 srt:SubsidiariesMember cma:FourPercentSubordinatedNotesDue2025Member 2019-12-31 0000028412 srt:ParentCompanyMember cma:A3.70NotesDue2023Member 2018-12-31 0000028412 srt:ParentCompanyMember cma:A3.70NotesDue2023Member 2019-12-31 0000028412 srt:ParentCompanyMember cma:ThreePointEightZeroPercentSubNotesDue2026Member 2018-12-31 0000028412 srt:SubsidiariesMember cma:FloatingratebasedonFHLBauctionratedue2028Member 2018-12-31 0000028412 srt:SubsidiariesMember cma:SevenPointEightSevenFivePercentageSubordinatedNoteDue2026Member 2018-12-31 0000028412 srt:SubsidiariesMember cma:TwoPointFivePercentageNotesDue2024MemberDomain 2018-12-31 0000028412 srt:SubsidiariesMember srt:MaximumMember cma:FloatingRateBasedonFHLBAuctionDue2026Member 2019-01-01 2019-12-31 0000028412 srt:ParentCompanyMember cma:ThreePointEightZeroPercentSubNotesDue2026Member 2018-01-01 2018-12-31 0000028412 srt:SubsidiariesMember cma:FourPercentSubordinatedNotesDue2025Member 2019-01-01 2019-12-31 0000028412 srt:SubsidiariesMember cma:TwoPointFivePercentageNotesDue2020MemberDomainDomain 2018-01-01 2018-12-31 0000028412 srt:SubsidiariesMember cma:FourPercentSubordinatedNotesDue2025Member 2018-01-01 2018-12-31 0000028412 srt:ParentCompanyMember cma:A4.00NotesDue2029Member 2019-01-01 2019-12-31 0000028412 srt:ParentCompanyMember cma:TwoPointOneTwoFivePercentageNotesDue2019MemberDomain 2019-01-01 2019-12-31 0000028412 srt:SubsidiariesMember cma:TwoPointFivePercentageNotesDue2020MemberDomainDomain 2019-01-01 2019-12-31 0000028412 srt:SubsidiariesMember cma:SevenPointEightSevenFivePercentageSubordinatedNoteDue2026Member 2019-01-01 2019-12-31 0000028412 srt:ParentCompanyMember cma:TwoPointOneTwoFivePercentageNotesDue2019MemberDomain 2018-01-01 2018-12-31 0000028412 srt:SubsidiariesMember cma:TwoPointFivePercentageNotesDue2024MemberDomain 2019-01-01 2019-12-31 0000028412 srt:SubsidiariesMember cma:SevenPointEightSevenFivePercentageSubordinatedNoteDue2026Member 2018-01-01 2018-12-31 0000028412 srt:ParentCompanyMember cma:A3.70NotesDue2023Member 2019-01-01 2019-12-31 0000028412 srt:ParentCompanyMember cma:ThreePointEightZeroPercentSubNotesDue2026Member 2019-01-01 2019-12-31 0000028412 srt:SubsidiariesMember srt:MinimumMember cma:FloatingRateBasedonFHLBAuctionDue2026Member 2019-01-01 2019-12-31 0000028412 srt:SubsidiariesMember cma:FloatingratebasedonFHLBauctionratedue2028Member 2019-01-01 2019-12-31 0000028412 us-gaap:RestrictedStockMember 2019-12-31 0000028412 us-gaap:WarrantMember 2018-01-01 2018-12-31 0000028412 us-gaap:WarrantMember 2019-01-01 2019-12-31 0000028412 cma:ShareRepurchaseProgramMember us-gaap:CommonStockMember 2019-01-01 2019-12-31 0000028412 cma:ShareRepurchaseProgramMember us-gaap:CommonStockMember 2017-01-01 2017-12-31 0000028412 us-gaap:WarrantMember 2017-01-01 2017-12-31 0000028412 us-gaap:StockOptionMember 2019-12-31 0000028412 cma:ShareRepurchaseProgramMember us-gaap:CommonStockMember 2018-01-01 2018-12-31 0000028412 us-gaap:EmployeeStockOptionMember 2018-01-01 2018-12-31 0000028412 us-gaap:EmployeeStockOptionMember 2019-01-01 2019-12-31 0000028412 us-gaap:EmployeeStockOptionMember 2017-01-01 2017-12-31 0000028412 srt:MinimumMember us-gaap:EmployeeStockOptionMember 2019-01-01 2019-12-31 0000028412 srt:MaximumMember us-gaap:EmployeeStockOptionMember 2018-01-01 2018-12-31 0000028412 srt:MinimumMember us-gaap:EmployeeStockOptionMember 2018-01-01 2018-12-31 0000028412 srt:MaximumMember us-gaap:EmployeeStockOptionMember 2019-01-01 2019-12-31 0000028412 us-gaap:RestrictedStockUnitsRSUMember 2019-01-01 2019-12-31 0000028412 us-gaap:RestrictedStockMember 2019-01-01 2019-12-31 0000028412 us-gaap:RestrictedStockMember 2017-01-01 2017-12-31 0000028412 us-gaap:RestrictedStockUnitsRSUMember 2017-01-01 2017-12-31 0000028412 us-gaap:RestrictedStockUnitsRSUMember 2018-01-01 2018-12-31 0000028412 us-gaap:RestrictedStockMember 2018-01-01 2018-12-31 0000028412 us-gaap:RestrictedStockMember 2018-12-31 0000028412 us-gaap:EmployeeStockOptionMember 2019-01-01 2019-12-31 0000028412 us-gaap:EmployeeStockOptionMember 2019-12-31 0000028412 us-gaap:EmployeeStockOptionMember 2018-12-31 0000028412 us-gaap:RestrictedStockUnitsRSUMember cma:PerformanceConditionsMember 2019-12-31 0000028412 us-gaap:RestrictedStockUnitsRSUMember cma:ServiceConditionsMember 2018-12-31 0000028412 us-gaap:RestrictedStockUnitsRSUMember cma:ServiceConditionsMember 2019-01-01 2019-12-31 0000028412 us-gaap:RestrictedStockUnitsRSUMember cma:PerformanceConditionsMember 2018-12-31 0000028412 us-gaap:RestrictedStockUnitsRSUMember cma:PerformanceConditionsMember 2019-01-01 2019-12-31 0000028412 us-gaap:RestrictedStockUnitsRSUMember cma:ServiceConditionsMember 2019-12-31 0000028412 srt:MaximumMember us-gaap:RestrictedStockMember 2019-01-01 2019-12-31 0000028412 srt:MinimumMember us-gaap:RestrictedStockMember 2019-01-01 2019-12-31 0000028412 srt:MaximumMember us-gaap:EmployeeStockOptionMember 2019-01-01 2019-12-31 0000028412 srt:MinimumMember us-gaap:RestrictedStockUnitsRSUMember 2019-01-01 2019-12-31 0000028412 srt:MaximumMember us-gaap:RestrictedStockUnitsRSUMember 2019-01-01 2019-12-31 0000028412 srt:MinimumMember us-gaap:EmployeeStockOptionMember 2019-01-01 2019-12-31 0000028412 us-gaap:CommercialPaperMember us-gaap:CashAndCashEquivalentsMember us-gaap:FairValueInputsLevel3Member 2018-12-31 0000028412 us-gaap:DebtSecuritiesMember us-gaap:CollateralizedMortgageObligationsMember 2019-12-31 0000028412 us-gaap:EquitySecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:CommonStockMember 2018-12-31 0000028412 us-gaap:PrivatePlacementMember us-gaap:FairValueInputsLevel3Member 2019-12-31 0000028412 us-gaap:DebtSecuritiesMember cma:CorporateAndMunicipalBondsAndNotesMember 2019-12-31 0000028412 us-gaap:DebtSecuritiesMember us-gaap:FairValueInputsLevel2Member us-gaap:USTreasuryAndGovernmentMember 2019-12-31 0000028412 us-gaap:PrivatePlacementMember us-gaap:FairValueInputsLevel1Member 2019-12-31 0000028412 us-gaap:DebtSecuritiesMember us-gaap:FairValueInputsLevel2Member cma:CorporateAndMunicipalBondsAndNotesMember 2018-12-31 0000028412 us-gaap:DebtSecuritiesMember us-gaap:USTreasuryAndGovernmentMember 2019-12-31 0000028412 us-gaap:CommercialPaperMember us-gaap:CashAndCashEquivalentsMember us-gaap:FairValueInputsLevel1Member 2018-12-31 0000028412 us-gaap:DebtSecuritiesMember us-gaap:FairValueInputsLevel1Member us-gaap:USTreasuryAndGovernmentMember 2018-12-31 0000028412 us-gaap:FairValueInputsLevel2Member 2018-12-31 0000028412 us-gaap:DebtSecuritiesMember us-gaap:FairValueInputsLevel2Member us-gaap:USTreasuryAndGovernmentMember 2018-12-31 0000028412 us-gaap:EquitySecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:CommonStockMember 2019-12-31 0000028412 us-gaap:DebtSecuritiesMember us-gaap:FairValueInputsLevel2Member us-gaap:CollateralizedMortgageObligationsMember 2018-12-31 0000028412 us-gaap:DebtSecuritiesMember us-gaap:FairValueInputsLevel3Member cma:CorporateAndMunicipalBondsAndNotesMember 2019-12-31 0000028412 us-gaap:PrivatePlacementMember us-gaap:FairValueInputsLevel3Member 2018-12-31 0000028412 us-gaap:FairValueInputsLevel1Member 2018-12-31 0000028412 us-gaap:PrivatePlacementMember us-gaap:FairValueInputsLevel1Member 2018-12-31 0000028412 us-gaap:DebtSecuritiesMember us-gaap:FairValueInputsLevel1Member us-gaap:CollateralizedMortgageObligationsMember 2018-12-31 0000028412 us-gaap:EquitySecuritiesMember us-gaap:FairValueInputsLevel1Member us-gaap:CommonStockMember 2018-12-31 0000028412 us-gaap:DebtSecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:USTreasuryAndGovernmentMember 2019-12-31 0000028412 us-gaap:DebtSecuritiesMember us-gaap:FairValueInputsLevel1Member us-gaap:USTreasuryAndGovernmentMember 2019-12-31 0000028412 us-gaap:DebtSecuritiesMember us-gaap:USTreasuryAndGovernmentMember 2018-12-31 0000028412 us-gaap:PrivatePlacementMember 2018-12-31 0000028412 us-gaap:FairValueInputsLevel1Member 2019-12-31 0000028412 us-gaap:EquitySecuritiesMember us-gaap:FairValueInputsLevel2Member us-gaap:CommonStockMember 2018-12-31 0000028412 us-gaap:PrivatePlacementMember 2019-12-31 0000028412 us-gaap:CommercialPaperMember us-gaap:CashAndCashEquivalentsMember 2018-12-31 0000028412 us-gaap:EquitySecuritiesMember us-gaap:FairValueInputsLevel2Member us-gaap:CommonStockMember 2019-12-31 0000028412 us-gaap:DebtSecuritiesMember cma:CorporateAndMunicipalBondsAndNotesMember 2018-12-31 0000028412 us-gaap:FairValueInputsLevel3Member 2018-12-31 0000028412 us-gaap:PrivatePlacementMember us-gaap:FairValueInputsLevel2Member 2018-12-31 0000028412 us-gaap:DebtSecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:CollateralizedMortgageObligationsMember 2018-12-31 0000028412 us-gaap:EquitySecuritiesMember us-gaap:FairValueInputsLevel1Member us-gaap:CommonStockMember 2019-12-31 0000028412 us-gaap:DebtSecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:USTreasuryAndGovernmentMember 2018-12-31 0000028412 us-gaap:DebtSecuritiesMember us-gaap:FairValueInputsLevel3Member cma:CorporateAndMunicipalBondsAndNotesMember 2018-12-31 0000028412 us-gaap:EquitySecuritiesMember us-gaap:FairValueInputsLevel1Member us-gaap:EquityFundsMember 2019-12-31 0000028412 us-gaap:EquitySecuritiesMember us-gaap:CommonStockMember 2019-12-31 0000028412 us-gaap:FairValueInputsLevel2Member 2019-12-31 0000028412 us-gaap:EquitySecuritiesMember us-gaap:EquityFundsMember 2019-12-31 0000028412 us-gaap:CommercialPaperMember us-gaap:CashAndCashEquivalentsMember us-gaap:FairValueInputsLevel2Member 2018-12-31 0000028412 us-gaap:DebtSecuritiesMember us-gaap:FairValueInputsLevel1Member cma:CorporateAndMunicipalBondsAndNotesMember 2019-12-31 0000028412 us-gaap:DebtSecuritiesMember us-gaap:FairValueInputsLevel1Member cma:CorporateAndMunicipalBondsAndNotesMember 2018-12-31 0000028412 us-gaap:DebtSecuritiesMember cma:CollectiveInvestmentFundsMember 2018-12-31 0000028412 us-gaap:DebtSecuritiesMember us-gaap:FairValueInputsLevel2Member cma:CorporateAndMunicipalBondsAndNotesMember 2019-12-31 0000028412 us-gaap:PrivatePlacementMember us-gaap:FairValueInputsLevel2Member 2019-12-31 0000028412 us-gaap:DebtSecuritiesMember us-gaap:FairValueInputsLevel2Member us-gaap:CollateralizedMortgageObligationsMember 2019-12-31 0000028412 us-gaap:DebtSecuritiesMember us-gaap:CollateralizedMortgageObligationsMember 2018-12-31 0000028412 us-gaap:EquitySecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:EquityFundsMember 2019-12-31 0000028412 us-gaap:EquitySecuritiesMember us-gaap:FairValueInputsLevel2Member us-gaap:EquityFundsMember 2019-12-31 0000028412 us-gaap:FairValueInputsLevel3Member 2019-12-31 0000028412 us-gaap:DebtSecuritiesMember cma:CollectiveInvestmentFundsMember 2019-12-31 0000028412 us-gaap:DebtSecuritiesMember us-gaap:FairValueInputsLevel3Member us-gaap:CollateralizedMortgageObligationsMember 2019-12-31 0000028412 us-gaap:EquitySecuritiesMember us-gaap:CommonStockMember 2018-12-31 0000028412 us-gaap:DebtSecuritiesMember us-gaap:FairValueInputsLevel1Member us-gaap:CollateralizedMortgageObligationsMember 2019-12-31 0000028412 us-gaap:OtherPensionPlansDefinedBenefitMember 2019-12-31 0000028412 us-gaap:PensionPlansDefinedBenefitMember 2019-12-31 0000028412 us-gaap:OtherPostretirementBenefitPlansDefinedBenefitMember 2019-12-31 0000028412 us-gaap:PrivatePlacementMember 2019-01-01 2019-12-31 0000028412 us-gaap:PrivatePlacementMember 2018-01-01 2018-12-31 0000028412 us-gaap:PrivatePlacementMember 2017-12-31 0000028412 us-gaap:OtherPostretirementBenefitPlansDefinedBenefitMember 2018-12-31 0000028412 us-gaap:OtherPensionPlansDefinedBenefitMember 2017-12-31 0000028412 us-gaap:PensionPlansDefinedBenefitMember 2018-01-01 2018-12-31 0000028412 us-gaap:OtherPensionPlansDefinedBenefitMember 2018-01-01 2018-12-31 0000028412 us-gaap:OtherPostretirementBenefitPlansDefinedBenefitMember 2017-12-31 0000028412 us-gaap:OtherPostretirementBenefitPlansDefinedBenefitMember 2019-01-01 2019-12-31 0000028412 us-gaap:OtherPostretirementBenefitPlansDefinedBenefitMember 2018-01-01 2018-12-31 0000028412 us-gaap:PensionPlansDefinedBenefitMember 2019-01-01 2019-12-31 0000028412 us-gaap:OtherPensionPlansDefinedBenefitMember 2018-12-31 0000028412 us-gaap:PensionPlansDefinedBenefitMember 2018-12-31 0000028412 us-gaap:OtherPensionPlansDefinedBenefitMember 2019-01-01 2019-12-31 0000028412 us-gaap:PensionPlansDefinedBenefitMember 2017-12-31 0000028412 us-gaap:PensionPlansDefinedBenefitMember 2017-01-01 2017-12-31 0000028412 us-gaap:OtherPensionPlansDefinedBenefitMember 2017-01-01 2017-12-31 0000028412 us-gaap:OtherPostretirementBenefitPlansDefinedBenefitMember 2017-01-01 2017-12-31 0000028412 srt:MaximumMember us-gaap:DebtSecuritiesMember us-gaap:PensionPlansDefinedBenefitMember 2019-01-01 2019-12-31 0000028412 srt:MinimumMember us-gaap:DebtSecuritiesMember us-gaap:PensionPlansDefinedBenefitMember 2019-01-01 2019-12-31 0000028412 srt:MaximumMember us-gaap:InternalRevenueServiceIRSMember 2019-01-01 2019-12-31 0000028412 srt:MaximumMember us-gaap:StateAndLocalJurisdictionMember 2019-01-01 2019-12-31 0000028412 srt:MinimumMember 2019-01-01 2019-12-31 0000028412 srt:MinimumMember us-gaap:StateAndLocalJurisdictionMember 2019-01-01 2019-12-31 0000028412 srt:MaximumMember 2019-01-01 2019-12-31 0000028412 srt:MinimumMember us-gaap:InternalRevenueServiceIRSMember 2019-01-01 2019-12-31 0000028412 cma:ComericaIncorporatedMember 2018-12-31 0000028412 cma:ComericaBankMember 2019-12-31 0000028412 cma:ComericaIncorporatedMember 2019-12-31 0000028412 cma:ComericaBankMember 2018-12-31 0000028412 cma:ComericaIncorporatedMember 2019-10-01 2019-12-31 0000028412 cma:ComericaBankMember 2019-10-01 2019-12-31 0000028412 cma:ComericaBankMember 2018-10-01 2018-12-31 0000028412 cma:ComericaIncorporatedMember 2018-10-01 2018-12-31 0000028412 srt:MaximumMember us-gaap:PendingLitigationMember 2019-12-31 0000028412 cma:ButteLocalDevelopmentv.MastersGroupv.ComericaBankMember 2014-01-16 2014-01-17 0000028412 srt:MinimumMember us-gaap:PendingLitigationMember 2019-12-31 0000028412 cma:Other1Member 2017-01-01 2017-12-31 0000028412 cma:WealthManagementMember 2017-01-01 2017-12-31 0000028412 cma:RetailBankMember 2017-01-01 2017-12-31 0000028412 cma:BusinessBankMember 2017-01-01 2017-12-31 0000028412 cma:FinanceMember 2017-01-01 2017-12-31 0000028412 cma:FinanceOtherMember 2019-01-01 2019-12-31 0000028412 cma:OtherMarketsMember 2019-01-01 2019-12-31 0000028412 stpr:CA 2019-01-01 2019-12-31 0000028412 stpr:MI 2019-01-01 2019-12-31 0000028412 stpr:TX 2019-01-01 2019-12-31 0000028412 cma:FinanceMember 2019-01-01 2019-12-31 0000028412 cma:WealthManagementMember 2018-01-01 2018-12-31 0000028412 cma:RetailBankMember 2018-01-01 2018-12-31 0000028412 cma:FinanceMember 2018-01-01 2018-12-31 0000028412 cma:BusinessBankMember 2019-01-01 2019-12-31 0000028412 cma:BusinessBankMember 2018-01-01 2018-12-31 0000028412 cma:WealthManagementMember 2019-01-01 2019-12-31 0000028412 cma:Other1Member 2018-01-01 2018-12-31 0000028412 cma:Other1Member 2019-01-01 2019-12-31 0000028412 cma:RetailBankMember 2019-01-01 2019-12-31 0000028412 cma:FinanceOtherMember 2018-01-01 2018-12-31 0000028412 cma:OtherMarketsMember 2017-01-01 2017-12-31 0000028412 cma:FinanceOtherMember 2017-01-01 2017-12-31 0000028412 stpr:CA 2018-01-01 2018-12-31 0000028412 stpr:TX 2017-01-01 2017-12-31 0000028412 stpr:TX 2018-01-01 2018-12-31 0000028412 stpr:CA 2017-01-01 2017-12-31 0000028412 stpr:MI 2018-01-01 2018-12-31 0000028412 stpr:MI 2017-01-01 2017-12-31 0000028412 cma:OtherMarketsMember 2018-01-01 2018-12-31 0000028412 srt:ParentCompanyMember 2019-01-01 2019-12-31 0000028412 srt:ParentCompanyMember 2018-01-01 2018-12-31 0000028412 srt:ParentCompanyMember 2017-01-01 2017-12-31 0000028412 srt:ParentCompanyMember 2016-12-31 0000028412 srt:ParentCompanyMember 2017-12-31 0000028412 2019-07-01 2019-09-30 0000028412 2019-01-01 2019-03-31 0000028412 2019-04-01 2019-06-30 0000028412 2019-10-01 2019-12-31 0000028412 2018-01-01 2018-03-31 0000028412 2017-10-01 2017-12-31 0000028412 2018-07-01 2018-09-30 0000028412 2018-10-01 2018-12-31 0000028412 us-gaap:DepositAccountMember cma:WealthManagementMember 2018-01-01 2018-12-31 0000028412 cma:NoninterestDomain 2019-01-01 2019-12-31 0000028412 us-gaap:CommercialLoanMember 2019-01-01 2019-12-31 0000028412 cma:FinanceOther1MemberDomain 2017-01-01 2017-12-31 0000028412 us-gaap:DepositAccountMember cma:BusinessBankMember 2019-01-01 2019-12-31 0000028412 us-gaap:CreditAndDebitCardMember cma:RetailBankMember 2019-01-01 2019-12-31 0000028412 us-gaap:CommercialLoanMember cma:WealthManagementMember 2019-01-01 2019-12-31 0000028412 cma:BrokerageCommissionsRevenueMember cma:FinanceOther1MemberDomain 2018-01-01 2018-12-31 0000028412 cma:BrokerageCommissionsRevenueMember cma:FinanceOther1MemberDomain 2019-01-01 2019-12-31 0000028412 cma:BrokerageCommissionsRevenueMember 2019-01-01 2019-12-31 0000028412 us-gaap:CreditAndDebitCardMember 2018-01-01 2018-12-31 0000028412 us-gaap:FiduciaryAndTrustMember 2018-01-01 2018-12-31 0000028412 cma:NoninterestDomain cma:BusinessBankMember 2019-01-01 2019-12-31 0000028412 us-gaap:DepositAccountMember 2018-01-01 2018-12-31 0000028412 us-gaap:DepositAccountMember cma:BusinessBankMember 2018-01-01 2018-12-31 0000028412 us-gaap:FiduciaryAndTrustMember cma:FinanceOther1MemberDomain 2019-01-01 2019-12-31 0000028412 cma:BrokerageCommissionsRevenueMember cma:WealthManagementMember 2018-01-01 2018-12-31 0000028412 us-gaap:DepositAccountMember 2019-01-01 2019-12-31 0000028412 us-gaap:CommercialLoanMember cma:WealthManagementMember 2018-01-01 2018-12-31 0000028412 us-gaap:FiduciaryAndTrustMember cma:WealthManagementMember 2018-01-01 2018-12-31 0000028412 us-gaap:FiduciaryAndTrustMember cma:FinanceOther1MemberDomain 2018-01-01 2018-12-31 0000028412 us-gaap:DepositAccountMember cma:FinanceOther1MemberDomain 2019-01-01 2019-12-31 0000028412 us-gaap:FiduciaryAndTrustMember cma:RetailBankMember 2019-01-01 2019-12-31 0000028412 us-gaap:CommercialLoanMember cma:FinanceOther1MemberDomain 2019-01-01 2019-12-31 0000028412 cma:BrokerageCommissionsRevenueMember cma:BusinessBankMember 2018-01-01 2018-12-31 0000028412 cma:BrokerageCommissionsRevenueMember cma:WealthManagementMember 2019-01-01 2019-12-31 0000028412 cma:NoninterestDomain cma:RetailBankMember 2019-01-01 2019-12-31 0000028412 us-gaap:DepositAccountMember cma:RetailBankMember 2018-01-01 2018-12-31 0000028412 cma:FinanceOther1MemberDomain 2019-01-01 2019-12-31 0000028412 us-gaap:FiduciaryAndTrustMember 2019-01-01 2019-12-31 0000028412 cma:BrokerageCommissionsRevenueMember cma:RetailBankMember 2019-01-01 2019-12-31 0000028412 us-gaap:CommercialLoanMember cma:FinanceOther1MemberDomain 2018-01-01 2018-12-31 0000028412 us-gaap:CreditAndDebitCardMember 2019-01-01 2019-12-31 0000028412 us-gaap:FiduciaryAndTrustMember cma:WealthManagementMember 2019-01-01 2019-12-31 0000028412 cma:BrokerageCommissionsRevenueMember 2018-01-01 2018-12-31 0000028412 us-gaap:FiduciaryAndTrustMember cma:RetailBankMember 2018-01-01 2018-12-31 0000028412 us-gaap:FiduciaryAndTrustMember cma:BusinessBankMember 2018-01-01 2018-12-31 0000028412 us-gaap:CreditAndDebitCardMember cma:WealthManagementMember 2019-01-01 2019-12-31 0000028412 us-gaap:CommercialLoanMember cma:BusinessBankMember 2019-01-01 2019-12-31 0000028412 cma:NoninterestDomain cma:WealthManagementMember 2018-01-01 2018-12-31 0000028412 cma:FinanceOther1MemberDomain 2018-01-01 2018-12-31 0000028412 cma:BrokerageCommissionsRevenueMember cma:BusinessBankMember 2019-01-01 2019-12-31 0000028412 us-gaap:CommercialLoanMember cma:RetailBankMember 2018-01-01 2018-12-31 0000028412 us-gaap:DepositAccountMember cma:WealthManagementMember 2019-01-01 2019-12-31 0000028412 us-gaap:CommercialLoanMember 2018-01-01 2018-12-31 0000028412 us-gaap:FiduciaryAndTrustMember cma:BusinessBankMember 2019-01-01 2019-12-31 0000028412 cma:BrokerageCommissionsRevenueMember cma:RetailBankMember 2018-01-01 2018-12-31 0000028412 cma:NoninterestDomain cma:RetailBankMember 2018-01-01 2018-12-31 0000028412 cma:NoninterestDomain cma:FinanceOther1MemberDomain 2019-01-01 2019-12-31 0000028412 us-gaap:CreditAndDebitCardMember cma:FinanceOther1MemberDomain 2018-01-01 2018-12-31 0000028412 us-gaap:CommercialLoanMember cma:RetailBankMember 2019-01-01 2019-12-31 0000028412 us-gaap:CreditAndDebitCardMember cma:FinanceOther1MemberDomain 2019-01-01 2019-12-31 0000028412 cma:NoninterestDomain cma:BusinessBankMember 2018-01-01 2018-12-31 0000028412 cma:NoninterestDomain cma:WealthManagementMember 2019-01-01 2019-12-31 0000028412 cma:NoninterestDomain cma:FinanceOther1MemberDomain 2018-01-01 2018-12-31 0000028412 us-gaap:CreditAndDebitCardMember cma:RetailBankMember 2018-01-01 2018-12-31 0000028412 us-gaap:CreditAndDebitCardMember cma:BusinessBankMember 2018-01-01 2018-12-31 0000028412 cma:NoninterestDomain 2018-01-01 2018-12-31 0000028412 us-gaap:CommercialLoanMember cma:BusinessBankMember 2018-01-01 2018-12-31 0000028412 us-gaap:DepositAccountMember cma:RetailBankMember 2019-01-01 2019-12-31 0000028412 us-gaap:CreditAndDebitCardMember cma:WealthManagementMember 2018-01-01 2018-12-31 0000028412 us-gaap:DepositAccountMember cma:FinanceOther1MemberDomain 2018-01-01 2018-12-31 0000028412 us-gaap:CreditAndDebitCardMember cma:BusinessBankMember 2019-01-01 2019-12-31 0000028412 us-gaap:DifferenceBetweenRevenueGuidanceInEffectBeforeAndAfterTopic606Member 2018-01-01 2018-12-31 iso4217:USD xbrli:shares xbrli:shares iso4217:USD xbrli:pure cma:markets cma:segments
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM 10-K
Annual Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

For the fiscal year ended December 31, 2019
Or
Transition Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934
For the transition period from __________________________ to __________________________
Commission file number 1-10706
Comerica Incorporated
(Exact Name of Registrant as Specified in Its Charter)
Delaware
 
38-1998421
(State or Other Jurisdiction of Incorporation)
 
(IRS Employer Identification Number)
Comerica Bank Tower
1717 Main Street, MC 6404
Dallas, Texas 75201
(Address of Principal Executive Offices) (Zip Code)
(214) 462-6831
(Registrant’s Telephone Number, Including Area Code)
Securities registered pursuant to Section 12(b) of
the Exchange Act:
Title of each class
Trading symbol
Name of each exchange on which registered
Common Stock, $5 par value
CMA
New York Stock Exchange
Securities registered pursuant to Section 12(g) of the
Exchange Act:
None
Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes ý No o
Indicate by check mark if registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act. Yes o No ý
Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes ý No o
Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§ 232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes ý No o
Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.
Large accelerated filer

Accelerated filer


Non-accelerated filer

Smaller reporting company
 
 
Emerging growth company
If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.     o
Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes  No ý
At June 28, 2019 (the last business day of the registrant’s most recently completed second fiscal quarter), the registrant’s common stock, $5 par value, held by non-affiliates had an aggregate market value of approximately $10.7 billion based on the closing price on the New York Stock Exchange on that date of $72.64 per share. For purposes of this Form 10-K only, it has been assumed that all common shares Comerica’s Trust Department holds for Comerica’s employee plans, and all common shares the registrant’s directors and executive officers hold, are shares held by affiliates.
At February 7, 2020, the registrant had outstanding 141,346,049 shares of its common stock, $5 par value.
Documents Incorporated by Reference:
Part III: Items 10-14—Proxy Statement for the Annual Meeting of Shareholders to be held April 28, 2020.


Table of Contents

TABLE OF CONTENTS