10-Q 1 cbu-20240331x10q.htm 10-Q
0000723188--12-312024Q1COMMUNITY BANK SYSTEM, INC.P3YP2YP5Yhttp://fasb.org/us-gaap/2023#InterestReceivable000http://communitybankna.com/20240331#ValuationTechniqueFairValueOfCollateralMemberhttp://communitybankna.com/20240331#MeasurementInputEstimatedCostOfDisposalOrMarketAdjustmentMemberhttp://communitybankna.com/20240331#ValuationTechniqueFairValueOfCollateralMemberhttp://communitybankna.com/20240331#MeasurementInputEstimatedCostOfDisposalOrMarketAdjustmentMemberhttp://fasb.org/us-gaap/2023#ValuationTechniqueDiscountedCashFlowMemberhttp://communitybankna.com/20240331#MeasurementInputEmbeddedServicingValueMemberhttp://fasb.org/us-gaap/2023#ValuationTechniqueDiscountedCashFlowMemberhttp://fasb.org/us-gaap/2023#MeasurementInputConstantPrepaymentRateMemberhttp://fasb.org/us-gaap/2023#MeasurementInputDiscountRateMemberhttp://communitybankna.com/20240331#MeasurementInputAdequateCompensationMemberhttp://fasb.org/us-gaap/2023#ValuationTechniqueDiscountedCashFlowMemberhttp://fasb.org/us-gaap/2023#MeasurementInputDiscountRateMemberhttp://communitybankna.com/20240331#ProbabilityOfAchievementOfRetainedRevenueLevelMemberhttp://communitybankna.com/20240331#ValuationTechniqueFairValueOfCollateralMemberhttp://communitybankna.com/20240331#MeasurementInputEstimatedCostOfDisposalOrMarketAdjustmentMemberhttp://communitybankna.com/20240331#ValuationTechniqueFairValueOfCollateralMemberhttp://communitybankna.com/20240331#MeasurementInputEstimatedCostOfDisposalOrMarketAdjustmentMemberhttp://fasb.org/us-gaap/2023#ValuationTechniqueDiscountedCashFlowMemberhttp://communitybankna.com/20240331#MeasurementInputEmbeddedServicingValueMemberhttp://fasb.org/us-gaap/2023#ValuationTechniqueDiscountedCashFlowMemberhttp://fasb.org/us-gaap/2023#MeasurementInputConstantPrepaymentRateMemberhttp://fasb.org/us-gaap/2023#MeasurementInputDiscountRateMemberhttp://communitybankna.com/20240331#MeasurementInputAdequateCompensationMemberhttp://fasb.org/us-gaap/2023#ValuationTechniqueDiscountedCashFlowMemberhttp://fasb.org/us-gaap/2023#MeasurementInputDiscountRateMemberhttp://communitybankna.com/20240331#ProbabilityOfAchievementOfRetainedRevenueLevelMemberfalse0000723188us-gaap:TreasuryStockCommonMember2024-03-310000723188us-gaap:RetainedEarningsMember2024-03-310000723188us-gaap:DeferredCompensationShareBasedPaymentsMember2024-03-310000723188us-gaap:AdditionalPaidInCapitalMember2024-03-310000723188us-gaap:AccumulatedOtherComprehensiveIncomeMember2024-03-310000723188us-gaap:TreasuryStockCommonMember2023-12-310000723188us-gaap:RetainedEarningsMember2023-12-310000723188us-gaap:DeferredCompensationShareBasedPaymentsMember2023-12-310000723188us-gaap:AdditionalPaidInCapitalMember2023-12-310000723188us-gaap:AccumulatedOtherComprehensiveIncomeMember2023-12-310000723188us-gaap:TreasuryStockCommonMember2023-03-310000723188us-gaap:RetainedEarningsMember2023-03-310000723188us-gaap:DeferredCompensationShareBasedPaymentsMember2023-03-310000723188us-gaap:AdditionalPaidInCapitalMember2023-03-310000723188us-gaap:AccumulatedOtherComprehensiveIncomeMember2023-03-310000723188us-gaap:TreasuryStockCommonMember2022-12-310000723188us-gaap:RetainedEarningsMember2022-12-310000723188us-gaap:DeferredCompensationShareBasedPaymentsMember2022-12-310000723188us-gaap:AdditionalPaidInCapitalMember2022-12-310000723188us-gaap:AccumulatedOtherComprehensiveIncomeMember2022-12-310000723188us-gaap:FairValueInputsLevel3Memberus-gaap:MeasurementInputConstantPrepaymentRateMember2024-03-310000723188us-gaap:FairValueInputsLevel3Memberus-gaap:MeasurementInputConstantPrepaymentRateMember2023-12-310000723188srt:WeightedAverageMemberus-gaap:FairValueInputsLevel3Memberus-gaap:MeasurementInputConstantPrepaymentRateMemberus-gaap:ValuationTechniqueDiscountedCashFlowMember2024-03-310000723188srt:MinimumMemberus-gaap:FairValueInputsLevel3Memberus-gaap:MeasurementInputConstantPrepaymentRateMemberus-gaap:ValuationTechniqueDiscountedCashFlowMember2024-03-310000723188srt:MaximumMemberus-gaap:FairValueInputsLevel3Memberus-gaap:MeasurementInputConstantPrepaymentRateMemberus-gaap:ValuationTechniqueDiscountedCashFlowMember2024-03-310000723188srt:WeightedAverageMemberus-gaap:FairValueInputsLevel3Memberus-gaap:MeasurementInputConstantPrepaymentRateMemberus-gaap:ValuationTechniqueDiscountedCashFlowMember2023-12-310000723188srt:MinimumMemberus-gaap:FairValueInputsLevel3Memberus-gaap:MeasurementInputConstantPrepaymentRateMemberus-gaap:ValuationTechniqueDiscountedCashFlowMember2023-12-310000723188srt:MaximumMemberus-gaap:FairValueInputsLevel3Memberus-gaap:MeasurementInputConstantPrepaymentRateMemberus-gaap:ValuationTechniqueDiscountedCashFlowMember2023-12-310000723188us-gaap:FairValueInputsLevel3Memberus-gaap:MeasurementInputConstantPrepaymentRateMemberus-gaap:ValuationTechniqueDiscountedCashFlowMember2024-03-310000723188us-gaap:FairValueInputsLevel3Memberus-gaap:MeasurementInputConstantPrepaymentRateMemberus-gaap:ValuationTechniqueDiscountedCashFlowMember2023-12-310000723188cbu:AxiomMember2023-03-012023-03-010000723188cbu:ThomasGregoryAssociatesMember2023-07-012023-09-300000723188srt:WeightedAverageMemberus-gaap:FairValueInputsLevel3Membercbu:MeasurementInputEstimatedCostOfDisposalOrMarketAdjustmentMembercbu:ValuationTechniqueFairValueOfCollateralMember2024-03-310000723188srt:MinimumMemberus-gaap:FairValueInputsLevel3Membercbu:MeasurementInputEstimatedCostOfDisposalOrMarketAdjustmentMembercbu:ValuationTechniqueFairValueOfCollateralMember2024-03-310000723188srt:MaximumMemberus-gaap:FairValueInputsLevel3Membercbu:MeasurementInputEstimatedCostOfDisposalOrMarketAdjustmentMembercbu:ValuationTechniqueFairValueOfCollateralMember2024-03-310000723188srt:MinimumMembercbu:MeasurementInputEstimatedCostOfDisposalOrMarketAdjustmentMembercbu:ValuationTechniqueFairValueOfCollateralMember2024-03-310000723188srt:MaximumMembercbu:MeasurementInputEstimatedCostOfDisposalOrMarketAdjustmentMembercbu:ValuationTechniqueFairValueOfCollateralMember2024-03-310000723188srt:WeightedAverageMemberus-gaap:FairValueInputsLevel3Membercbu:MeasurementInputEstimatedCostOfDisposalOrMarketAdjustmentMembercbu:ValuationTechniqueFairValueOfCollateralMember2023-12-310000723188srt:MinimumMemberus-gaap:FairValueInputsLevel3Membercbu:MeasurementInputEstimatedCostOfDisposalOrMarketAdjustmentMembercbu:ValuationTechniqueFairValueOfCollateralMember2023-12-310000723188srt:MaximumMemberus-gaap:FairValueInputsLevel3Membercbu:MeasurementInputEstimatedCostOfDisposalOrMarketAdjustmentMembercbu:ValuationTechniqueFairValueOfCollateralMember2023-12-310000723188us-gaap:AccumulatedOtherComprehensiveIncomeMember2024-01-012024-03-310000723188us-gaap:AccumulatedOtherComprehensiveIncomeMember2023-01-012023-03-310000723188cbu:AxiomMember2024-01-012024-03-310000723188cbu:AxiomMember2023-01-012023-03-310000723188us-gaap:IntersegmentEliminationMember2024-01-012024-03-310000723188us-gaap:IntersegmentEliminationMember2023-01-012023-03-310000723188us-gaap:FairValueInputsLevel3Membercbu:MeasurementInputEstimatedCostOfDisposalOrMarketAdjustmentMember2024-03-310000723188us-gaap:FairValueInputsLevel3Membercbu:MeasurementInputEstimatedCostOfDisposalOrMarketAdjustmentMember2023-12-310000723188us-gaap:OperatingSegmentsMember2024-01-012024-03-310000723188us-gaap:OperatingSegmentsMember2023-01-012023-03-310000723188us-gaap:OtherIntangibleAssetsMember2024-03-310000723188us-gaap:CoreDepositsMember2024-03-310000723188us-gaap:OtherIntangibleAssetsMember2023-12-310000723188us-gaap:CoreDepositsMember2023-12-310000723188us-gaap:ConsumerPortfolioSegmentMembercbu:CommercialRealEstateNonOwnerOccupiedMemberus-gaap:ExtendedMaturityMember2024-01-012024-03-310000723188us-gaap:ResidentialPortfolioSegmentMembercbu:HomeEquityReceivablesMemberus-gaap:FinancialAssetNotPastDueMember2024-01-012024-03-310000723188us-gaap:ResidentialPortfolioSegmentMembercbu:HomeEquityReceivablesMembercbu:FinancingReceivablesNonAccrualMember2024-01-012024-03-310000723188us-gaap:ResidentialPortfolioSegmentMembercbu:HomeEquityReceivablesMembercbu:FinancingReceivables90PlusDaysPastDueAndStillAccruingMember2024-01-012024-03-310000723188us-gaap:ResidentialPortfolioSegmentMembercbu:HomeEquityReceivablesMembercbu:FinancingReceivables30To89DaysPastDueMember2024-01-012024-03-310000723188us-gaap:ConsumerPortfolioSegmentMemberus-gaap:ResidentialMortgageMemberus-gaap:FinancialAssetNotPastDueMember2024-01-012024-03-310000723188us-gaap:ConsumerPortfolioSegmentMemberus-gaap:ResidentialMortgageMembercbu:FinancingReceivablesNonAccrualMember2024-01-012024-03-310000723188us-gaap:ConsumerPortfolioSegmentMemberus-gaap:ResidentialMortgageMembercbu:FinancingReceivables90PlusDaysPastDueAndStillAccruingMember2024-01-012024-03-310000723188us-gaap:ConsumerPortfolioSegmentMemberus-gaap:ResidentialMortgageMembercbu:FinancingReceivables30To89DaysPastDueMember2024-01-012024-03-310000723188us-gaap:CommercialPortfolioSegmentMembercbu:CommercialRealEstateOwnerOccupiedMemberus-gaap:FinancialAssetNotPastDueMember2024-01-012024-03-310000723188us-gaap:CommercialPortfolioSegmentMembercbu:CommercialRealEstateOwnerOccupiedMemberus-gaap:ExtendedMaturityMember2024-01-012024-03-310000723188us-gaap:CommercialPortfolioSegmentMembercbu:CommercialRealEstateOwnerOccupiedMembercbu:FinancingReceivablesNonAccrualMember2024-01-012024-03-310000723188us-gaap:CommercialPortfolioSegmentMembercbu:CommercialRealEstateOwnerOccupiedMembercbu:FinancingReceivables90PlusDaysPastDueAndStillAccruingMember2024-01-012024-03-310000723188us-gaap:CommercialPortfolioSegmentMembercbu:CommercialRealEstateOwnerOccupiedMembercbu:FinancingReceivables30To89DaysPastDueMember2024-01-012024-03-310000723188us-gaap:CommercialPortfolioSegmentMembercbu:CommercialRealEstateNonOwnerOccupiedMemberus-gaap:FinancialAssetNotPastDueMember2024-01-012024-03-310000723188us-gaap:CommercialPortfolioSegmentMembercbu:CommercialRealEstateNonOwnerOccupiedMemberus-gaap:ExtendedMaturityMember2024-01-012024-03-310000723188us-gaap:CommercialPortfolioSegmentMembercbu:CommercialRealEstateNonOwnerOccupiedMembercbu:FinancingReceivablesNonAccrualMember2024-01-012024-03-310000723188us-gaap:CommercialPortfolioSegmentMembercbu:CommercialRealEstateNonOwnerOccupiedMembercbu:FinancingReceivables90PlusDaysPastDueAndStillAccruingMember2024-01-012024-03-310000723188us-gaap:CommercialPortfolioSegmentMembercbu:CommercialRealEstateNonOwnerOccupiedMembercbu:FinancingReceivables30To89DaysPastDueMember2024-01-012024-03-310000723188us-gaap:CommercialPortfolioSegmentMembercbu:CommercialIndustrialAndOtherBusinessLoansMemberus-gaap:FinancialAssetNotPastDueMember2024-01-012024-03-310000723188us-gaap:CommercialPortfolioSegmentMembercbu:CommercialIndustrialAndOtherBusinessLoansMemberus-gaap:ExtendedMaturityMember2024-01-012024-03-310000723188us-gaap:CommercialPortfolioSegmentMembercbu:CommercialIndustrialAndOtherBusinessLoansMembercbu:FinancingReceivablesNonAccrualMember2024-01-012024-03-310000723188us-gaap:CommercialPortfolioSegmentMembercbu:CommercialIndustrialAndOtherBusinessLoansMembercbu:FinancingReceivables90PlusDaysPastDueAndStillAccruingMember2024-01-012024-03-310000723188us-gaap:CommercialPortfolioSegmentMembercbu:CommercialIndustrialAndOtherBusinessLoansMembercbu:FinancingReceivables30To89DaysPastDueMember2024-01-012024-03-310000723188us-gaap:ConsumerPortfolioSegmentMemberus-gaap:ResidentialMortgageMember2024-01-012024-03-310000723188us-gaap:CommercialPortfolioSegmentMembercbu:CommercialRealEstateOwnerOccupiedMember2024-01-012024-03-310000723188us-gaap:CommercialPortfolioSegmentMembercbu:CommercialRealEstateNonOwnerOccupiedMember2024-01-012024-03-310000723188us-gaap:CommercialPortfolioSegmentMembercbu:CommercialIndustrialAndOtherBusinessLoansMember2024-01-012024-03-310000723188us-gaap:FinancialAssetNotPastDueMember2024-01-012024-03-310000723188us-gaap:ExtendedMaturityMember2024-01-012024-03-310000723188cbu:FinancingReceivablesNonAccrualMember2024-01-012024-03-310000723188cbu:FinancingReceivables90PlusDaysPastDueAndStillAccruingMember2024-01-012024-03-310000723188cbu:FinancingReceivables30To89DaysPastDueMember2024-01-012024-03-310000723188cbu:LegacyLoanMemberus-gaap:ResidentialPortfolioSegmentMembercbu:HomeEquityReceivablesMemberus-gaap:FinancialAssetPastDueMember2024-03-310000723188cbu:LegacyLoanMemberus-gaap:ResidentialPortfolioSegmentMembercbu:HomeEquityReceivablesMemberus-gaap:FinancialAssetNotPastDueMember2024-03-310000723188cbu:LegacyLoanMemberus-gaap:ResidentialPortfolioSegmentMembercbu:HomeEquityReceivablesMembercbu:FinancingReceivables90PlusDaysPastDueAndStillAccruingMember2024-03-310000723188cbu:LegacyLoanMemberus-gaap:ResidentialPortfolioSegmentMembercbu:HomeEquityReceivablesMembercbu:FinancingReceivables30To89DaysPastDueMember2024-03-310000723188cbu:LegacyLoanMemberus-gaap:ResidentialPortfolioSegmentMembercbu:CommercialRealEstateOwnerOccupiedMemberus-gaap:FinancialAssetPastDueMember2024-03-310000723188cbu:LegacyLoanMemberus-gaap:ResidentialPortfolioSegmentMembercbu:CommercialRealEstateOwnerOccupiedMemberus-gaap:FinancialAssetNotPastDueMember2024-03-310000723188cbu:LegacyLoanMemberus-gaap:ResidentialPortfolioSegmentMembercbu:CommercialRealEstateOwnerOccupiedMembercbu:FinancingReceivables90PlusDaysPastDueAndStillAccruingMember2024-03-310000723188cbu:LegacyLoanMemberus-gaap:ResidentialPortfolioSegmentMembercbu:CommercialRealEstateOwnerOccupiedMembercbu:FinancingReceivables30To89DaysPastDueMember2024-03-310000723188cbu:LegacyLoanMemberus-gaap:ConsumerPortfolioSegmentMembercbu:ConsumerInstallmentIndirectMemberus-gaap:FinancialAssetPastDueMember2024-03-310000723188cbu:LegacyLoanMemberus-gaap:ConsumerPortfolioSegmentMembercbu:ConsumerInstallmentIndirectMemberus-gaap:FinancialAssetNotPastDueMember2024-03-310000723188cbu:LegacyLoanMemberus-gaap:ConsumerPortfolioSegmentMembercbu:ConsumerInstallmentIndirectMembercbu:FinancingReceivables90PlusDaysPastDueAndStillAccruingMember2024-03-310000723188cbu:LegacyLoanMemberus-gaap:ConsumerPortfolioSegmentMembercbu:ConsumerInstallmentIndirectMembercbu:FinancingReceivables30To89DaysPastDueMember2024-03-310000723188cbu:LegacyLoanMemberus-gaap:ConsumerPortfolioSegmentMembercbu:ConsumerInstallmentDirectMemberus-gaap:FinancialAssetPastDueMember2024-03-310000723188cbu:LegacyLoanMemberus-gaap:ConsumerPortfolioSegmentMembercbu:ConsumerInstallmentDirectMemberus-gaap:FinancialAssetNotPastDueMember2024-03-310000723188cbu:LegacyLoanMemberus-gaap:ConsumerPortfolioSegmentMembercbu:ConsumerInstallmentDirectMembercbu:FinancingReceivables90PlusDaysPastDueAndStillAccruingMember2024-03-310000723188cbu:LegacyLoanMemberus-gaap:ConsumerPortfolioSegmentMembercbu:ConsumerInstallmentDirectMembercbu:FinancingReceivables30To89DaysPastDueMember2024-03-310000723188cbu:LegacyLoanMemberus-gaap:CommercialPortfolioSegmentMembercbu:CommercialRealEstateMultifamilyMemberus-gaap:FinancialAssetPastDueMember2024-03-310000723188cbu:LegacyLoanMemberus-gaap:CommercialPortfolioSegmentMembercbu:CommercialRealEstateMultifamilyMemberus-gaap:FinancialAssetNotPastDueMember2024-03-310000723188cbu:LegacyLoanMemberus-gaap:CommercialPortfolioSegmentMembercbu:CommercialRealEstateMultifamilyMembercbu:FinancingReceivables90PlusDaysPastDueAndStillAccruingMember2024-03-310000723188cbu:LegacyLoanMemberus-gaap:CommercialPortfolioSegmentMembercbu:CommercialRealEstateMultifamilyMembercbu:FinancingReceivables30To89DaysPastDueMember2024-03-310000723188cbu:LegacyLoanMemberus-gaap:ResidentialPortfolioSegmentMembercbu:HomeEquityReceivablesMember2024-03-310000723188cbu:LegacyLoanMemberus-gaap:ResidentialPortfolioSegmentMembercbu:CommercialRealEstateOwnerOccupiedMember2024-03-310000723188cbu:LegacyLoanMemberus-gaap:ConsumerPortfolioSegmentMembercbu:ConsumerInstallmentIndirectMember2024-03-310000723188cbu:LegacyLoanMemberus-gaap:ConsumerPortfolioSegmentMembercbu:ConsumerInstallmentDirectMember2024-03-310000723188cbu:LegacyLoanMemberus-gaap:CommercialPortfolioSegmentMembercbu:CommercialRealEstateMultifamilyMember2024-03-310000723188cbu:FICOScoreLessThan720Memberus-gaap:PerformingFinancingReceivableMemberus-gaap:ResidentialMortgageMember2024-03-310000723188cbu:FICOScoreLessThan720Memberus-gaap:NonperformingFinancingReceivableMemberus-gaap:ResidentialMortgageMember2024-03-310000723188cbu:FICOScoreGreaterThanOrEqualTo720Memberus-gaap:PerformingFinancingReceivableMemberus-gaap:ResidentialMortgageMember2024-03-310000723188cbu:FICOScoreGreaterThanOrEqualTo720Memberus-gaap:NonperformingFinancingReceivableMemberus-gaap:ResidentialMortgageMember2024-03-310000723188us-gaap:ResidentialMortgageMemberus-gaap:FinancialAssetPastDueMember2024-03-310000723188us-gaap:ResidentialMortgageMemberus-gaap:FinancialAssetNotPastDueMember2024-03-310000723188us-gaap:ResidentialMortgageMembercbu:FinancingReceivables90PlusDaysPastDueAndStillAccruingMember2024-03-310000723188us-gaap:ResidentialMortgageMembercbu:FinancingReceivables30To89DaysPastDueMember2024-03-310000723188us-gaap:PerformingFinancingReceivableMembercbu:HomeEquityReceivablesMember2024-03-310000723188us-gaap:PerformingFinancingReceivableMembercbu:ConsumerInstallmentIndirectMember2024-03-310000723188us-gaap:PerformingFinancingReceivableMembercbu:ConsumerInstallmentDirectMember2024-03-310000723188us-gaap:NonperformingFinancingReceivableMembercbu:HomeEquityReceivablesMember2024-03-310000723188us-gaap:NonperformingFinancingReceivableMembercbu:ConsumerInstallmentIndirectMember2024-03-310000723188us-gaap:NonperformingFinancingReceivableMembercbu:ConsumerInstallmentDirectMember2024-03-310000723188us-gaap:ConsumerPortfolioSegmentMembercbu:HomeEquityReceivablesMember2024-03-310000723188us-gaap:CommercialPortfolioSegmentMembercbu:CommercialRealEstateOwnerOccupiedMember2024-03-310000723188us-gaap:CommercialPortfolioSegmentMembercbu:CommercialRealEstateNonOwnerOccupiedMember2024-03-310000723188us-gaap:CommercialPortfolioSegmentMembercbu:CommercialRealEstateMultifamilyMember2024-03-310000723188us-gaap:CommercialPortfolioSegmentMembercbu:CommercialIndustrialAndOtherBusinessLoansMember2024-03-310000723188us-gaap:CommercialLoanMemberus-gaap:SubstandardMember2024-03-310000723188us-gaap:CommercialLoanMemberus-gaap:SpecialMentionMember2024-03-310000723188us-gaap:CommercialLoanMemberus-gaap:PassMember2024-03-310000723188us-gaap:CommercialLoanMemberus-gaap:DoubtfulMember2024-03-310000723188cbu:LegacyLoanMemberus-gaap:FinancialAssetPastDueMember2024-03-310000723188cbu:LegacyLoanMemberus-gaap:FinancialAssetNotPastDueMember2024-03-310000723188cbu:LegacyLoanMembercbu:FinancingReceivables90PlusDaysPastDueAndStillAccruingMember2024-03-310000723188cbu:LegacyLoanMembercbu:FinancingReceivables30To89DaysPastDueMember2024-03-310000723188cbu:FICOScoreLessThan720Memberus-gaap:ResidentialMortgageMember2024-03-310000723188cbu:FICOScoreGreaterThanOrEqualTo720Memberus-gaap:ResidentialMortgageMember2024-03-310000723188cbu:CommercialRealEstateOwnerOccupiedMemberus-gaap:SubstandardMember2024-03-310000723188cbu:CommercialRealEstateOwnerOccupiedMemberus-gaap:SpecialMentionMember2024-03-310000723188cbu:CommercialRealEstateOwnerOccupiedMemberus-gaap:PassMember2024-03-310000723188cbu:CommercialRealEstateOwnerOccupiedMemberus-gaap:DoubtfulMember2024-03-310000723188cbu:CommercialRealEstateNonOwnerOccupiedMemberus-gaap:SubstandardMember2024-03-310000723188cbu:CommercialRealEstateNonOwnerOccupiedMemberus-gaap:SpecialMentionMember2024-03-310000723188cbu:CommercialRealEstateNonOwnerOccupiedMemberus-gaap:PassMember2024-03-310000723188cbu:CommercialRealEstateNonOwnerOccupiedMemberus-gaap:FinancialAssetPastDueMember2024-03-310000723188cbu:CommercialRealEstateNonOwnerOccupiedMemberus-gaap:FinancialAssetNotPastDueMember2024-03-310000723188cbu:CommercialRealEstateNonOwnerOccupiedMemberus-gaap:DoubtfulMember2024-03-310000723188cbu:CommercialRealEstateNonOwnerOccupiedMembercbu:FinancingReceivables90PlusDaysPastDueAndStillAccruingMember2024-03-310000723188cbu:CommercialRealEstateNonOwnerOccupiedMembercbu:FinancingReceivables30To89DaysPastDueMember2024-03-310000723188cbu:CommercialRealEstateMultifamilyMemberus-gaap:SubstandardMember2024-03-310000723188cbu:CommercialRealEstateMultifamilyMemberus-gaap:SpecialMentionMember2024-03-310000723188cbu:CommercialRealEstateMultifamilyMemberus-gaap:PassMember2024-03-310000723188cbu:CommercialRealEstateMultifamilyMemberus-gaap:DoubtfulMember2024-03-310000723188cbu:CommercialIndustrialAndOtherBusinessLoansMemberus-gaap:SubstandardMember2024-03-310000723188cbu:CommercialIndustrialAndOtherBusinessLoansMemberus-gaap:SpecialMentionMember2024-03-310000723188cbu:CommercialIndustrialAndOtherBusinessLoansMemberus-gaap:PassMember2024-03-310000723188cbu:CommercialIndustrialAndOtherBusinessLoansMemberus-gaap:FinancialAssetPastDueMember2024-03-310000723188cbu:CommercialIndustrialAndOtherBusinessLoansMemberus-gaap:FinancialAssetNotPastDueMember2024-03-310000723188cbu:CommercialIndustrialAndOtherBusinessLoansMemberus-gaap:DoubtfulMember2024-03-310000723188cbu:CommercialIndustrialAndOtherBusinessLoansMembercbu:FinancingReceivables90PlusDaysPastDueAndStillAccruingMember2024-03-310000723188cbu:CommercialIndustrialAndOtherBusinessLoansMembercbu:FinancingReceivables30To89DaysPastDueMember2024-03-310000723188us-gaap:ResidentialMortgageMember2024-03-310000723188us-gaap:CommercialLoanMember2024-03-310000723188cbu:LegacyLoanMember2024-03-310000723188cbu:HomeEquityReceivablesMember2024-03-310000723188cbu:ConsumerInstallmentIndirectMember2024-03-310000723188cbu:ConsumerInstallmentDirectMember2024-03-310000723188cbu:CommercialRealEstateOwnerOccupiedMember2024-03-310000723188cbu:CommercialRealEstateNonOwnerOccupiedMember2024-03-310000723188cbu:CommercialRealEstateMultifamilyMember2024-03-310000723188cbu:CommercialIndustrialAndOtherBusinessLoansMember2024-03-310000723188cbu:LegacyLoanMemberus-gaap:ResidentialPortfolioSegmentMemberus-gaap:ResidentialMortgageMemberus-gaap:FinancialAssetPastDueMember2023-12-310000723188cbu:LegacyLoanMemberus-gaap:ResidentialPortfolioSegmentMemberus-gaap:ResidentialMortgageMemberus-gaap:FinancialAssetNotPastDueMember2023-12-310000723188cbu:LegacyLoanMemberus-gaap:ResidentialPortfolioSegmentMemberus-gaap:ResidentialMortgageMembercbu:FinancingReceivables90PlusDaysPastDueAndStillAccruingMember2023-12-310000723188cbu:LegacyLoanMemberus-gaap:ResidentialPortfolioSegmentMemberus-gaap:ResidentialMortgageMembercbu:FinancingReceivables30To89DaysPastDueMember2023-12-310000723188cbu:LegacyLoanMemberus-gaap:ResidentialPortfolioSegmentMembercbu:HomeEquityReceivablesMemberus-gaap:FinancialAssetPastDueMember2023-12-310000723188cbu:LegacyLoanMemberus-gaap:ResidentialPortfolioSegmentMembercbu:HomeEquityReceivablesMemberus-gaap:FinancialAssetNotPastDueMember2023-12-310000723188cbu:LegacyLoanMemberus-gaap:ResidentialPortfolioSegmentMembercbu:HomeEquityReceivablesMembercbu:FinancingReceivables90PlusDaysPastDueAndStillAccruingMember2023-12-310000723188cbu:LegacyLoanMemberus-gaap:ResidentialPortfolioSegmentMembercbu:HomeEquityReceivablesMembercbu:FinancingReceivables30To89DaysPastDueMember2023-12-310000723188cbu:LegacyLoanMemberus-gaap:ResidentialPortfolioSegmentMembercbu:CommercialRealEstateOwnerOccupiedMemberus-gaap:FinancialAssetPastDueMember2023-12-310000723188cbu:LegacyLoanMemberus-gaap:ResidentialPortfolioSegmentMembercbu:CommercialRealEstateOwnerOccupiedMemberus-gaap:FinancialAssetNotPastDueMember2023-12-310000723188cbu:LegacyLoanMemberus-gaap:ResidentialPortfolioSegmentMembercbu:CommercialRealEstateOwnerOccupiedMembercbu:FinancingReceivables90PlusDaysPastDueAndStillAccruingMember2023-12-310000723188cbu:LegacyLoanMemberus-gaap:ResidentialPortfolioSegmentMembercbu:CommercialRealEstateOwnerOccupiedMembercbu:FinancingReceivables30To89DaysPastDueMember2023-12-310000723188cbu:LegacyLoanMemberus-gaap:ConsumerPortfolioSegmentMembercbu:ConsumerInstallmentIndirectMemberus-gaap:FinancialAssetPastDueMember2023-12-310000723188cbu:LegacyLoanMemberus-gaap:ConsumerPortfolioSegmentMembercbu:ConsumerInstallmentIndirectMemberus-gaap:FinancialAssetNotPastDueMember2023-12-310000723188cbu:LegacyLoanMemberus-gaap:ConsumerPortfolioSegmentMembercbu:ConsumerInstallmentIndirectMembercbu:FinancingReceivables90PlusDaysPastDueAndStillAccruingMember2023-12-310000723188cbu:LegacyLoanMemberus-gaap:ConsumerPortfolioSegmentMembercbu:ConsumerInstallmentIndirectMembercbu:FinancingReceivables30To89DaysPastDueMember2023-12-310000723188cbu:LegacyLoanMemberus-gaap:ConsumerPortfolioSegmentMembercbu:ConsumerInstallmentDirectMemberus-gaap:FinancialAssetPastDueMember2023-12-310000723188cbu:LegacyLoanMemberus-gaap:ConsumerPortfolioSegmentMembercbu:ConsumerInstallmentDirectMemberus-gaap:FinancialAssetNotPastDueMember2023-12-310000723188cbu:LegacyLoanMemberus-gaap:ConsumerPortfolioSegmentMembercbu:ConsumerInstallmentDirectMembercbu:FinancingReceivables90PlusDaysPastDueAndStillAccruingMember2023-12-310000723188cbu:LegacyLoanMemberus-gaap:ConsumerPortfolioSegmentMembercbu:ConsumerInstallmentDirectMembercbu:FinancingReceivables30To89DaysPastDueMember2023-12-310000723188cbu:LegacyLoanMemberus-gaap:ConsumerPortfolioSegmentMembercbu:CommercialRealEstateNonOwnerOccupiedMemberus-gaap:FinancialAssetPastDueMember2023-12-310000723188cbu:LegacyLoanMemberus-gaap:ConsumerPortfolioSegmentMembercbu:CommercialRealEstateNonOwnerOccupiedMemberus-gaap:FinancialAssetNotPastDueMember2023-12-310000723188cbu:LegacyLoanMemberus-gaap:ConsumerPortfolioSegmentMembercbu:CommercialRealEstateNonOwnerOccupiedMembercbu:FinancingReceivables90PlusDaysPastDueAndStillAccruingMember2023-12-310000723188cbu:LegacyLoanMemberus-gaap:ConsumerPortfolioSegmentMembercbu:CommercialRealEstateNonOwnerOccupiedMembercbu:FinancingReceivables30To89DaysPastDueMember2023-12-310000723188cbu:LegacyLoanMemberus-gaap:ConsumerPortfolioSegmentMembercbu:CommercialIndustrialAndOtherBusinessLoansMemberus-gaap:FinancialAssetPastDueMember2023-12-310000723188cbu:LegacyLoanMemberus-gaap:ConsumerPortfolioSegmentMembercbu:CommercialIndustrialAndOtherBusinessLoansMemberus-gaap:FinancialAssetNotPastDueMember2023-12-310000723188cbu:LegacyLoanMemberus-gaap:ConsumerPortfolioSegmentMembercbu:CommercialIndustrialAndOtherBusinessLoansMembercbu:FinancingReceivables90PlusDaysPastDueAndStillAccruingMember2023-12-310000723188cbu:LegacyLoanMemberus-gaap:ConsumerPortfolioSegmentMembercbu:CommercialIndustrialAndOtherBusinessLoansMembercbu:FinancingReceivables30To89DaysPastDueMember2023-12-310000723188cbu:LegacyLoanMemberus-gaap:CommercialPortfolioSegmentMemberus-gaap:CommercialLoanMemberus-gaap:FinancialAssetPastDueMember2023-12-310000723188cbu:LegacyLoanMemberus-gaap:CommercialPortfolioSegmentMemberus-gaap:CommercialLoanMemberus-gaap:FinancialAssetNotPastDueMember2023-12-310000723188cbu:LegacyLoanMemberus-gaap:CommercialPortfolioSegmentMemberus-gaap:CommercialLoanMembercbu:FinancingReceivables90PlusDaysPastDueAndStillAccruingMember2023-12-310000723188cbu:LegacyLoanMemberus-gaap:CommercialPortfolioSegmentMemberus-gaap:CommercialLoanMembercbu:FinancingReceivables30To89DaysPastDueMember2023-12-310000723188cbu:LegacyLoanMemberus-gaap:ResidentialPortfolioSegmentMemberus-gaap:ResidentialMortgageMember2023-12-310000723188cbu:LegacyLoanMemberus-gaap:ResidentialPortfolioSegmentMembercbu:HomeEquityReceivablesMember2023-12-310000723188cbu:LegacyLoanMemberus-gaap:ResidentialPortfolioSegmentMembercbu:CommercialRealEstateOwnerOccupiedMember2023-12-310000723188cbu:LegacyLoanMemberus-gaap:ConsumerPortfolioSegmentMembercbu:ConsumerInstallmentIndirectMember2023-12-310000723188cbu:LegacyLoanMemberus-gaap:ConsumerPortfolioSegmentMembercbu:ConsumerInstallmentDirectMember2023-12-310000723188cbu:LegacyLoanMemberus-gaap:ConsumerPortfolioSegmentMembercbu:CommercialRealEstateNonOwnerOccupiedMember2023-12-310000723188cbu:LegacyLoanMemberus-gaap:ConsumerPortfolioSegmentMembercbu:CommercialIndustrialAndOtherBusinessLoansMember2023-12-310000723188cbu:LegacyLoanMemberus-gaap:CommercialPortfolioSegmentMemberus-gaap:CommercialLoanMember2023-12-310000723188cbu:FICOScoreLessThan720Memberus-gaap:PerformingFinancingReceivableMemberus-gaap:ResidentialMortgageMember2023-12-310000723188cbu:FICOScoreLessThan720Memberus-gaap:NonperformingFinancingReceivableMemberus-gaap:ResidentialMortgageMember2023-12-310000723188cbu:FICOScoreGreaterThanOrEqualTo720Memberus-gaap:PerformingFinancingReceivableMemberus-gaap:ResidentialMortgageMember2023-12-310000723188cbu:FICOScoreGreaterThanOrEqualTo720Memberus-gaap:NonperformingFinancingReceivableMemberus-gaap:ResidentialMortgageMember2023-12-310000723188us-gaap:PerformingFinancingReceivableMembercbu:HomeEquityReceivablesMember2023-12-310000723188us-gaap:PerformingFinancingReceivableMembercbu:ConsumerInstallmentIndirectMember2023-12-310000723188us-gaap:PerformingFinancingReceivableMembercbu:ConsumerInstallmentDirectMember2023-12-310000723188us-gaap:NonperformingFinancingReceivableMembercbu:HomeEquityReceivablesMember2023-12-310000723188us-gaap:NonperformingFinancingReceivableMembercbu:ConsumerInstallmentIndirectMember2023-12-310000723188us-gaap:NonperformingFinancingReceivableMembercbu:ConsumerInstallmentDirectMember2023-12-310000723188us-gaap:ConsumerPortfolioSegmentMembercbu:HomeEquityReceivablesMember2023-12-310000723188us-gaap:CommercialPortfolioSegmentMembercbu:CommercialRealEstateOwnerOccupiedMember2023-12-310000723188us-gaap:CommercialPortfolioSegmentMembercbu:CommercialRealEstateNonOwnerOccupiedMember2023-12-310000723188us-gaap:CommercialPortfolioSegmentMembercbu:CommercialRealEstateMultifamilyMember2023-12-310000723188us-gaap:CommercialPortfolioSegmentMembercbu:CommercialIndustrialAndOtherBusinessLoansMember2023-12-310000723188us-gaap:CommercialLoanMemberus-gaap:SubstandardMember2023-12-310000723188us-gaap:CommercialLoanMemberus-gaap:SpecialMentionMember2023-12-310000723188us-gaap:CommercialLoanMemberus-gaap:PassMember2023-12-310000723188us-gaap:CommercialLoanMemberus-gaap:DoubtfulMember2023-12-310000723188cbu:LegacyLoanMemberus-gaap:FinancialAssetPastDueMember2023-12-310000723188cbu:LegacyLoanMemberus-gaap:FinancialAssetNotPastDueMember2023-12-310000723188cbu:LegacyLoanMembercbu:FinancingReceivables90PlusDaysPastDueAndStillAccruingMember2023-12-310000723188cbu:LegacyLoanMembercbu:FinancingReceivables30To89DaysPastDueMember2023-12-310000723188cbu:FICOScoreLessThan720Memberus-gaap:ResidentialMortgageMember2023-12-310000723188cbu:FICOScoreGreaterThanOrEqualTo720Memberus-gaap:ResidentialMortgageMember2023-12-310000723188cbu:CommercialRealEstateOwnerOccupiedMemberus-gaap:SubstandardMember2023-12-310000723188cbu:CommercialRealEstateOwnerOccupiedMemberus-gaap:SpecialMentionMember2023-12-310000723188cbu:CommercialRealEstateOwnerOccupiedMemberus-gaap:PassMember2023-12-310000723188cbu:CommercialRealEstateOwnerOccupiedMemberus-gaap:DoubtfulMember2023-12-310000723188cbu:CommercialRealEstateNonOwnerOccupiedMemberus-gaap:SubstandardMember2023-12-310000723188cbu:CommercialRealEstateNonOwnerOccupiedMemberus-gaap:SpecialMentionMember2023-12-310000723188cbu:CommercialRealEstateNonOwnerOccupiedMemberus-gaap:PassMember2023-12-310000723188cbu:CommercialRealEstateNonOwnerOccupiedMemberus-gaap:DoubtfulMember2023-12-310000723188cbu:CommercialRealEstateMultifamilyMemberus-gaap:SubstandardMember2023-12-310000723188cbu:CommercialRealEstateMultifamilyMemberus-gaap:SpecialMentionMember2023-12-310000723188cbu:CommercialRealEstateMultifamilyMemberus-gaap:PassMember2023-12-310000723188cbu:CommercialRealEstateMultifamilyMemberus-gaap:DoubtfulMember2023-12-310000723188cbu:CommercialIndustrialAndOtherBusinessLoansMemberus-gaap:SubstandardMember2023-12-310000723188cbu:CommercialIndustrialAndOtherBusinessLoansMemberus-gaap:SpecialMentionMember2023-12-310000723188cbu:CommercialIndustrialAndOtherBusinessLoansMemberus-gaap:PassMember2023-12-310000723188cbu:CommercialIndustrialAndOtherBusinessLoansMemberus-gaap:DoubtfulMember2023-12-310000723188us-gaap:ResidentialMortgageMember2023-12-310000723188us-gaap:CommercialLoanMember2023-12-310000723188cbu:LegacyLoanMember2023-12-310000723188cbu:HomeEquityReceivablesMember2023-12-310000723188cbu:ConsumerInstallmentIndirectMember2023-12-310000723188cbu:ConsumerInstallmentDirectMember2023-12-310000723188cbu:CommercialRealEstateOwnerOccupiedMember2023-12-310000723188cbu:CommercialRealEstateNonOwnerOccupiedMember2023-12-310000723188cbu:CommercialRealEstateMultifamilyMember2023-12-310000723188cbu:CommercialIndustrialAndOtherBusinessLoansMember2023-12-310000723188us-gaap:ResidentialMortgageMember2024-01-012024-03-310000723188cbu:HomeEquityReceivablesMember2024-01-012024-03-310000723188cbu:ConsumerInstallmentIndirectMember2024-01-012024-03-310000723188cbu:ConsumerInstallmentDirectMember2024-01-012024-03-310000723188cbu:CommercialRealEstateOwnerOccupiedMember2024-01-012024-03-310000723188cbu:CommercialRealEstateNonOwnerOccupiedMember2024-01-012024-03-310000723188cbu:CommercialRealEstateMultifamilyMember2024-01-012024-03-310000723188cbu:CommercialIndustrialAndOtherBusinessLoansMember2024-01-012024-03-310000723188us-gaap:ResidentialMortgageMember2023-01-012023-12-310000723188cbu:HomeEquityReceivablesMember2023-01-012023-12-310000723188cbu:ConsumerInstallmentIndirectMember2023-01-012023-12-310000723188cbu:ConsumerInstallmentDirectMember2023-01-012023-12-310000723188cbu:CommercialRealEstateOwnerOccupiedMember2023-01-012023-12-310000723188cbu:CommercialRealEstateNonOwnerOccupiedMember2023-01-012023-12-310000723188cbu:CommercialRealEstateMultifamilyMember2023-01-012023-12-310000723188cbu:CommercialIndustrialAndOtherBusinessLoansMember2023-01-012023-12-310000723188us-gaap:ResidentialPortfolioSegmentMemberus-gaap:ResidentialMortgageMember2024-01-012024-03-310000723188us-gaap:ResidentialPortfolioSegmentMembercbu:HomeEquityReceivablesMember2024-01-012024-03-310000723188us-gaap:ConsumerPortfolioSegmentMembercbu:ConsumerInstallmentIndirectMember2024-01-012024-03-310000723188us-gaap:ConsumerPortfolioSegmentMembercbu:ConsumerInstallmentDirectMember2024-01-012024-03-310000723188us-gaap:CommercialPortfolioSegmentMemberus-gaap:CommercialLoanMember2024-01-012024-03-310000723188us-gaap:UnallocatedFinancingReceivablesMember2024-01-012024-03-310000723188cbu:AllowancesForCreditLossesMember2024-01-012024-03-310000723188us-gaap:ResidentialPortfolioSegmentMemberus-gaap:ResidentialMortgageMember2023-01-012023-03-310000723188us-gaap:ResidentialPortfolioSegmentMembercbu:HomeEquityReceivablesMember2023-01-012023-03-310000723188us-gaap:ConsumerPortfolioSegmentMembercbu:ConsumerInstallmentIndirectMember2023-01-012023-03-310000723188us-gaap:ConsumerPortfolioSegmentMembercbu:ConsumerInstallmentDirectMember2023-01-012023-03-310000723188us-gaap:CommercialPortfolioSegmentMemberus-gaap:CommercialLoanMember2023-01-012023-03-310000723188us-gaap:UnallocatedFinancingReceivablesMember2023-01-012023-03-310000723188cbu:AllowancesForCreditLossesMember2023-01-012023-03-310000723188us-gaap:AssetPledgedAsCollateralMembercbu:FederalHomeLoanBankAndFederalReserveBankAdvancesMember2024-03-310000723188us-gaap:CommercialLoanMember2024-01-012024-03-310000723188cbu:AllOtherLoansMember2024-01-012024-03-310000723188us-gaap:ResidentialPortfolioSegmentMemberus-gaap:ResidentialMortgageMember2024-03-310000723188us-gaap:ResidentialPortfolioSegmentMembercbu:HomeEquityReceivablesMember2024-03-310000723188us-gaap:ConsumerPortfolioSegmentMembercbu:ConsumerInstallmentIndirectMember2024-03-310000723188us-gaap:ConsumerPortfolioSegmentMembercbu:ConsumerInstallmentDirectMember2024-03-310000723188us-gaap:CommercialPortfolioSegmentMemberus-gaap:CommercialLoanMember2024-03-310000723188us-gaap:UnallocatedFinancingReceivablesMember2024-03-310000723188cbu:ElmiraSavingsBankMember2024-03-310000723188cbu:AllowancesForCreditLossesMember2024-03-310000723188us-gaap:ResidentialPortfolioSegmentMemberus-gaap:ResidentialMortgageMember2023-12-310000723188us-gaap:ResidentialPortfolioSegmentMembercbu:HomeEquityReceivablesMember2023-12-310000723188us-gaap:ConsumerPortfolioSegmentMembercbu:ConsumerInstallmentIndirectMember2023-12-310000723188us-gaap:ConsumerPortfolioSegmentMembercbu:ConsumerInstallmentDirectMember2023-12-310000723188us-gaap:CommercialPortfolioSegmentMemberus-gaap:CommercialLoanMember2023-12-310000723188us-gaap:UnallocatedFinancingReceivablesMember2023-12-310000723188cbu:ElmiraSavingsBankMember2023-12-310000723188cbu:AllowancesForCreditLossesMember2023-12-310000723188us-gaap:ResidentialPortfolioSegmentMemberus-gaap:ResidentialMortgageMember2023-03-310000723188us-gaap:ResidentialPortfolioSegmentMembercbu:HomeEquityReceivablesMember2023-03-310000723188us-gaap:ConsumerPortfolioSegmentMembercbu:ConsumerInstallmentIndirectMember2023-03-310000723188us-gaap:ConsumerPortfolioSegmentMembercbu:ConsumerInstallmentDirectMember2023-03-310000723188us-gaap:CommercialPortfolioSegmentMemberus-gaap:CommercialLoanMember2023-03-310000723188us-gaap:UnallocatedFinancingReceivablesMember2023-03-310000723188cbu:ElmiraSavingsBankMember2023-03-310000723188cbu:AllowancesForCreditLossesMember2023-03-310000723188us-gaap:ResidentialPortfolioSegmentMemberus-gaap:ResidentialMortgageMember2022-12-310000723188us-gaap:ResidentialPortfolioSegmentMembercbu:HomeEquityReceivablesMember2022-12-310000723188us-gaap:ConsumerPortfolioSegmentMembercbu:ConsumerInstallmentIndirectMember2022-12-310000723188us-gaap:ConsumerPortfolioSegmentMembercbu:ConsumerInstallmentDirectMember2022-12-310000723188us-gaap:CommercialPortfolioSegmentMemberus-gaap:CommercialLoanMember2022-12-310000723188us-gaap:UnallocatedFinancingReceivablesMember2022-12-310000723188cbu:AllowancesForCreditLossesMember2022-12-310000723188us-gaap:StandbyLettersOfCreditMember2024-03-310000723188us-gaap:CommitmentsToExtendCreditMember2024-03-310000723188us-gaap:StandbyLettersOfCreditMember2023-12-310000723188us-gaap:CommitmentsToExtendCreditMember2023-12-310000723188us-gaap:RetainedEarningsMember2024-01-012024-03-310000723188us-gaap:RetainedEarningsMember2023-01-012023-03-310000723188us-gaap:FairValueInputsLevel3Membercbu:MeasurementInputEmbeddedServicingValueMember2024-03-310000723188us-gaap:FairValueInputsLevel3Membercbu:MeasurementInputEmbeddedServicingValueMember2023-12-310000723188us-gaap:LoanOriginationCommitmentsMemberus-gaap:FairValueInputsLevel3Memberus-gaap:FairValueMeasurementsRecurringMember2024-03-310000723188us-gaap:LoanOriginationCommitmentsMemberus-gaap:FairValueInputsLevel2Memberus-gaap:FairValueMeasurementsRecurringMember2024-03-310000723188us-gaap:LoanOriginationCommitmentsMemberus-gaap:FairValueInputsLevel1Memberus-gaap:FairValueMeasurementsRecurringMember2024-03-310000723188us-gaap:ForwardContractsMemberus-gaap:FairValueInputsLevel3Memberus-gaap:FairValueMeasurementsRecurringMember2024-03-310000723188us-gaap:ForwardContractsMemberus-gaap:FairValueInputsLevel2Memberus-gaap:FairValueMeasurementsRecurringMember2024-03-310000723188us-gaap:ForwardContractsMemberus-gaap:FairValueInputsLevel1Memberus-gaap:FairValueMeasurementsRecurringMember2024-03-310000723188us-gaap:LoanOriginationCommitmentsMemberus-gaap:FairValueMeasurementsRecurringMember2024-03-310000723188us-gaap:ForwardContractsMemberus-gaap:FairValueMeasurementsRecurringMember2024-03-310000723188us-gaap:LoanOriginationCommitmentsMemberus-gaap:FairValueInputsLevel3Memberus-gaap:FairValueMeasurementsRecurringMember2023-12-310000723188us-gaap:LoanOriginationCommitmentsMemberus-gaap:FairValueInputsLevel2Memberus-gaap:FairValueMeasurementsRecurringMember2023-12-310000723188us-gaap:LoanOriginationCommitmentsMemberus-gaap:FairValueInputsLevel1Memberus-gaap:FairValueMeasurementsRecurringMember2023-12-310000723188us-gaap:ForwardContractsMemberus-gaap:FairValueInputsLevel3Memberus-gaap:FairValueMeasurementsRecurringMember2023-12-310000723188us-gaap:ForwardContractsMemberus-gaap:FairValueInputsLevel2Memberus-gaap:FairValueMeasurementsRecurringMember2023-12-310000723188us-gaap:ForwardContractsMemberus-gaap:FairValueInputsLevel1Memberus-gaap:FairValueMeasurementsRecurringMember2023-12-310000723188us-gaap:LoanOriginationCommitmentsMemberus-gaap:FairValueMeasurementsRecurringMember2023-12-310000723188us-gaap:ForwardContractsMemberus-gaap:FairValueMeasurementsRecurringMember2023-12-310000723188us-gaap:LoanOriginationCommitmentsMemberus-gaap:FairValueInputsLevel3Membercbu:MeasurementInputEmbeddedServicingValueMemberus-gaap:ValuationTechniqueDiscountedCashFlowMember2024-03-310000723188us-gaap:LoanOriginationCommitmentsMemberus-gaap:FairValueInputsLevel3Membercbu:MeasurementInputEmbeddedServicingValueMemberus-gaap:ValuationTechniqueDiscountedCashFlowMember2023-12-310000723188us-gaap:FairValueInputsLevel3Membercbu:MeasurementInputEmbeddedServicingValueMemberus-gaap:ValuationTechniqueDiscountedCashFlowMember2024-03-310000723188us-gaap:FairValueInputsLevel3Membercbu:MeasurementInputEmbeddedServicingValueMemberus-gaap:ValuationTechniqueDiscountedCashFlowMember2023-12-310000723188us-gaap:PensionPlansDefinedBenefitMember2024-01-012024-03-310000723188us-gaap:PensionPlansDefinedBenefitMember2023-01-012023-03-310000723188us-gaap:USTreasuryAndGovernmentMember2023-01-012023-03-310000723188us-gaap:FairValueInputsLevel3Memberus-gaap:FairValueMeasurementsRecurringMemberus-gaap:USTreasuryAndGovernmentMember2024-03-310000723188us-gaap:FairValueInputsLevel3Memberus-gaap:FairValueMeasurementsRecurringMemberus-gaap:USStatesAndPoliticalSubdivisionsMember2024-03-310000723188us-gaap:FairValueInputsLevel3Memberus-gaap:FairValueMeasurementsRecurringMemberus-gaap:MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember2024-03-310000723188us-gaap:FairValueInputsLevel3Memberus-gaap:FairValueMeasurementsRecurringMemberus-gaap:CorporateDebtSecuritiesMember2024-03-310000723188us-gaap:FairValueInputsLevel3Memberus-gaap:FairValueMeasurementsRecurringMembercbu:GovernmentAgencyCollateralizedMortgageObligationsMember2024-03-310000723188us-gaap:FairValueInputsLevel2Memberus-gaap:FairValueMeasurementsRecurringMemberus-gaap:USTreasuryAndGovernmentMember2024-03-310000723188us-gaap:FairValueInputsLevel2Memberus-gaap:FairValueMeasurementsRecurringMemberus-gaap:USStatesAndPoliticalSubdivisionsMember2024-03-310000723188us-gaap:FairValueInputsLevel2Memberus-gaap:FairValueMeasurementsRecurringMemberus-gaap:MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember2024-03-310000723188us-gaap:FairValueInputsLevel2Memberus-gaap:FairValueMeasurementsRecurringMemberus-gaap:CorporateDebtSecuritiesMember2024-03-310000723188us-gaap:FairValueInputsLevel2Memberus-gaap:FairValueMeasurementsRecurringMembercbu:GovernmentAgencyCollateralizedMortgageObligationsMember2024-03-310000723188us-gaap:FairValueInputsLevel1Memberus-gaap:FairValueMeasurementsRecurringMemberus-gaap:USTreasuryAndGovernmentMember2024-03-310000723188us-gaap:FairValueInputsLevel1Memberus-gaap:FairValueMeasurementsRecurringMemberus-gaap:USStatesAndPoliticalSubdivisionsMember2024-03-310000723188us-gaap:FairValueInputsLevel1Memberus-gaap:FairValueMeasurementsRecurringMemberus-gaap:MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember2024-03-310000723188us-gaap:FairValueInputsLevel1Memberus-gaap:FairValueMeasurementsRecurringMemberus-gaap:CorporateDebtSecuritiesMember2024-03-310000723188us-gaap:FairValueInputsLevel1Memberus-gaap:FairValueMeasurementsRecurringMembercbu:GovernmentAgencyCollateralizedMortgageObligationsMember2024-03-310000723188us-gaap:FairValueMeasurementsRecurringMemberus-gaap:USTreasuryAndGovernmentMember2024-03-310000723188us-gaap:FairValueMeasurementsRecurringMemberus-gaap:USStatesAndPoliticalSubdivisionsMember2024-03-310000723188us-gaap:FairValueMeasurementsRecurringMemberus-gaap:MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember2024-03-310000723188us-gaap:FairValueMeasurementsRecurringMemberus-gaap:CorporateDebtSecuritiesMember2024-03-310000723188us-gaap:FairValueMeasurementsRecurringMembercbu:GovernmentAgencyCollateralizedMortgageObligationsMember2024-03-310000723188us-gaap:FairValueInputsLevel3Memberus-gaap:FairValueMeasurementsRecurringMember2024-03-310000723188us-gaap:FairValueInputsLevel2Memberus-gaap:FairValueMeasurementsRecurringMember2024-03-310000723188us-gaap:FairValueInputsLevel1Memberus-gaap:FairValueMeasurementsRecurringMember2024-03-310000723188us-gaap:FairValueMeasurementsRecurringMember2024-03-310000723188us-gaap:FairValueInputsLevel3Memberus-gaap:FairValueMeasurementsRecurringMemberus-gaap:USTreasuryAndGovernmentMember2023-12-310000723188us-gaap:FairValueInputsLevel3Memberus-gaap:FairValueMeasurementsRecurringMemberus-gaap:USStatesAndPoliticalSubdivisionsMember2023-12-310000723188us-gaap:FairValueInputsLevel3Memberus-gaap:FairValueMeasurementsRecurringMemberus-gaap:MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember2023-12-310000723188us-gaap:FairValueInputsLevel3Memberus-gaap:FairValueMeasurementsRecurringMemberus-gaap:CorporateDebtSecuritiesMember2023-12-310000723188us-gaap:FairValueInputsLevel3Memberus-gaap:FairValueMeasurementsRecurringMembercbu:GovernmentAgencyCollateralizedMortgageObligationsMember2023-12-310000723188us-gaap:FairValueInputsLevel2Memberus-gaap:FairValueMeasurementsRecurringMemberus-gaap:USTreasuryAndGovernmentMember2023-12-310000723188us-gaap:FairValueInputsLevel2Memberus-gaap:FairValueMeasurementsRecurringMemberus-gaap:USStatesAndPoliticalSubdivisionsMember2023-12-310000723188us-gaap:FairValueInputsLevel2Memberus-gaap:FairValueMeasurementsRecurringMemberus-gaap:MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember2023-12-310000723188us-gaap:FairValueInputsLevel2Memberus-gaap:FairValueMeasurementsRecurringMemberus-gaap:CorporateDebtSecuritiesMember2023-12-310000723188us-gaap:FairValueInputsLevel2Memberus-gaap:FairValueMeasurementsRecurringMembercbu:GovernmentAgencyCollateralizedMortgageObligationsMember2023-12-310000723188us-gaap:FairValueInputsLevel1Memberus-gaap:FairValueMeasurementsRecurringMemberus-gaap:USTreasuryAndGovernmentMember2023-12-310000723188us-gaap:FairValueInputsLevel1Memberus-gaap:FairValueMeasurementsRecurringMemberus-gaap:USStatesAndPoliticalSubdivisionsMember2023-12-310000723188us-gaap:FairValueInputsLevel1Memberus-gaap:FairValueMeasurementsRecurringMemberus-gaap:MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember2023-12-310000723188us-gaap:FairValueInputsLevel1Memberus-gaap:FairValueMeasurementsRecurringMemberus-gaap:CorporateDebtSecuritiesMember2023-12-310000723188us-gaap:FairValueInputsLevel1Memberus-gaap:FairValueMeasurementsRecurringMembercbu:GovernmentAgencyCollateralizedMortgageObligationsMember2023-12-310000723188us-gaap:FairValueMeasurementsRecurringMemberus-gaap:USTreasuryAndGovernmentMember2023-12-310000723188us-gaap:FairValueMeasurementsRecurringMemberus-gaap:USStatesAndPoliticalSubdivisionsMember2023-12-310000723188us-gaap:FairValueMeasurementsRecurringMemberus-gaap:MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember2023-12-310000723188us-gaap:FairValueMeasurementsRecurringMemberus-gaap:CorporateDebtSecuritiesMember2023-12-310000723188us-gaap:FairValueMeasurementsRecurringMembercbu:GovernmentAgencyCollateralizedMortgageObligationsMember2023-12-310000723188us-gaap:FairValueInputsLevel3Memberus-gaap:FairValueMeasurementsRecurringMember2023-12-310000723188us-gaap:FairValueInputsLevel2Memberus-gaap:FairValueMeasurementsRecurringMember2023-12-310000723188us-gaap:FairValueInputsLevel1Memberus-gaap:FairValueMeasurementsRecurringMember2023-12-310000723188us-gaap:FairValueMeasurementsRecurringMember2023-12-310000723188us-gaap:USStatesAndPoliticalSubdivisionsMember2024-03-310000723188us-gaap:CorporateDebtSecuritiesMember2024-03-310000723188cbu:GovernmentAgencyCollateralizedMortgageObligationsMember2024-03-310000723188us-gaap:USStatesAndPoliticalSubdivisionsMember2023-12-310000723188us-gaap:MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember2023-12-310000723188us-gaap:CorporateDebtSecuritiesMember2023-12-310000723188us-gaap:USTreasuryAndGovernmentMemberus-gaap:SecuritiesSoldUnderAgreementsToRepurchaseMember2024-03-310000723188us-gaap:USTreasuryAndGovernmentMemberus-gaap:SecuritiesSoldUnderAgreementsToRepurchaseMember2023-12-310000723188us-gaap:ShortTermDebtMembercbu:BankTermFundingProgramMember2024-01-310000723188us-gaap:CommonStockMember2024-03-310000723188us-gaap:CommonStockMember2023-12-310000723188us-gaap:CommonStockMember2023-03-310000723188us-gaap:CommonStockMember2022-12-3100007231882022-12-310000723188cbu:CertainAssetsOfCreativePlanDesignLimitedMember2024-03-310000723188cbu:TotalAcquisitionsMember2023-12-310000723188cbu:OtherAcquisitionsMember2023-12-310000723188cbu:AxiomMember2023-12-310000723188cbu:AxiomMember2023-03-010000723188cbu:CertainAssetsOfFiveFinancialServiceCompaniesMember2023-12-310000723188us-gaap:FairValueInputsLevel3Memberus-gaap:MeasurementInputDiscountRateMember2024-03-310000723188us-gaap:FairValueInputsLevel3Memberus-gaap:MeasurementInputDiscountRateMember2023-12-310000723188us-gaap:FairValueInputsLevel3Membercbu:ProbabilityOfAchievementOfRetainedRevenueLevelMemberus-gaap:ValuationTechniqueDiscountedCashFlowMember2024-03-310000723188us-gaap:FairValueInputsLevel3Membercbu:ProbabilityOfAchievementOfRetainedRevenueLevelMemberus-gaap:ValuationTechniqueDiscountedCashFlowMember2023-12-310000723188srt:WeightedAverageMemberus-gaap:FairValueInputsLevel3Memberus-gaap:MeasurementInputDiscountRateMemberus-gaap:ValuationTechniqueDiscountedCashFlowMember2024-03-310000723188srt:WeightedAverageMemberus-gaap:FairValueInputsLevel3Membercbu:ProbabilityOfAchievementOfRetainedRevenueLevelMemberus-gaap:ValuationTechniqueDiscountedCashFlowMember2024-03-310000723188srt:MinimumMemberus-gaap:FairValueInputsLevel3Memberus-gaap:MeasurementInputDiscountRateMemberus-gaap:ValuationTechniqueDiscountedCashFlowMember2024-03-310000723188srt:MinimumMemberus-gaap:FairValueInputsLevel3Membercbu:ProbabilityOfAchievementOfRetainedRevenueLevelMemberus-gaap:ValuationTechniqueDiscountedCashFlowMember2024-03-310000723188srt:MaximumMemberus-gaap:FairValueInputsLevel3Memberus-gaap:MeasurementInputDiscountRateMemberus-gaap:ValuationTechniqueDiscountedCashFlowMember2024-03-310000723188srt:MaximumMemberus-gaap:FairValueInputsLevel3Membercbu:ProbabilityOfAchievementOfRetainedRevenueLevelMemberus-gaap:ValuationTechniqueDiscountedCashFlowMember2024-03-310000723188srt:MinimumMembercbu:CertainAssetsOfCreativePlanDesignLimitedMemberus-gaap:FairValueInputsLevel3Memberus-gaap:MeasurementInputDiscountRateMember2024-02-010000723188srt:MaximumMembercbu:CertainAssetsOfCreativePlanDesignLimitedMemberus-gaap:FairValueInputsLevel3Memberus-gaap:MeasurementInputDiscountRateMember2024-02-010000723188cbu:CertainAssetsOfCreativePlanDesignLimitedMemberus-gaap:FairValueInputsLevel3Memberus-gaap:MeasurementInputRevenueMultipleMember2024-02-010000723188srt:WeightedAverageMemberus-gaap:FairValueInputsLevel3Memberus-gaap:MeasurementInputDiscountRateMemberus-gaap:ValuationTechniqueDiscountedCashFlowMember2023-12-310000723188srt:MinimumMemberus-gaap:FairValueInputsLevel3Memberus-gaap:MeasurementInputDiscountRateMemberus-gaap:ValuationTechniqueDiscountedCashFlowMember2023-12-310000723188srt:MinimumMemberus-gaap:FairValueInputsLevel3Membercbu:ProbabilityOfAchievementOfRetainedRevenueLevelMemberus-gaap:ValuationTechniqueDiscountedCashFlowMember2023-12-310000723188srt:MaximumMemberus-gaap:FairValueInputsLevel3Memberus-gaap:MeasurementInputDiscountRateMemberus-gaap:ValuationTechniqueDiscountedCashFlowMember2023-12-310000723188cbu:CertainAssetsOfCreativePlanDesignLimitedMember2024-02-010000723188srt:MaximumMembercbu:FringeBenefitsDesignOfMinnesotaIncMember2023-01-012023-12-310000723188cbu:ThomasGregoryAssociatesMember2023-01-012023-12-310000723188cbu:NewYorkBasedInsuranceAgencyMemberus-gaap:SubsequentEventMember2024-04-012024-04-010000723188cbu:CertainAssetsOfFiveFinancialServiceCompaniesMember2023-01-012023-12-310000723188us-gaap:USTreasuryAndGovernmentMember2024-01-012024-03-310000723188us-gaap:USStatesAndPoliticalSubdivisionsMember2024-01-012024-03-310000723188us-gaap:MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember2024-01-012024-03-310000723188us-gaap:CorporateDebtSecuritiesMember2024-01-012024-03-310000723188cbu:GovernmentAgencyCollateralizedMortgageObligationsMember2024-01-012024-03-310000723188us-gaap:USTreasuryAndGovernmentMember2023-01-012023-12-310000723188us-gaap:USStatesAndPoliticalSubdivisionsMember2023-01-012023-12-310000723188us-gaap:MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember2023-01-012023-12-310000723188us-gaap:CorporateDebtSecuritiesMember2023-01-012023-12-310000723188cbu:GovernmentAgencyCollateralizedMortgageObligationsMember2023-01-012023-12-3100007231882023-01-012023-12-310000723188us-gaap:OperatingSegmentsMembercbu:WealthManagementSegmentMember2024-03-310000723188us-gaap:OperatingSegmentsMembercbu:InsuranceSegmentMember2024-03-310000723188us-gaap:OperatingSegmentsMembercbu:EmployeeBenefitServicesMember2024-03-310000723188us-gaap:OperatingSegmentsMembercbu:BankingAndCorporateSegmentMember2024-03-310000723188us-gaap:OperatingSegmentsMember2024-03-310000723188us-gaap:IntersegmentEliminationMember2024-03-310000723188us-gaap:OperatingSegmentsMembercbu:WealthManagementSegmentMember2023-03-310000723188us-gaap:OperatingSegmentsMembercbu:InsuranceSegmentMember2023-03-310000723188us-gaap:OperatingSegmentsMembercbu:EmployeeBenefitServicesMember2023-03-310000723188us-gaap:OperatingSegmentsMembercbu:BankingAndCorporateSegmentMember2023-03-310000723188us-gaap:OperatingSegmentsMember2023-03-310000723188us-gaap:IntersegmentEliminationMember2023-03-310000723188us-gaap:OperatingSegmentsMembercbu:WealthManagementSegmentMember2024-01-012024-03-310000723188us-gaap:OperatingSegmentsMembercbu:InsuranceSegmentMember2024-01-012024-03-310000723188us-gaap:OperatingSegmentsMembercbu:EmployeeBenefitServicesMember2024-01-012024-03-310000723188us-gaap:OperatingSegmentsMembercbu:BankingAndCorporateSegmentMember2024-01-012024-03-310000723188us-gaap:OperatingSegmentsMembercbu:WealthManagementSegmentMember2023-01-012023-03-310000723188us-gaap:OperatingSegmentsMembercbu:InsuranceSegmentMember2023-01-012023-03-310000723188us-gaap:OperatingSegmentsMembercbu:EmployeeBenefitServicesMember2023-01-012023-03-310000723188us-gaap:OperatingSegmentsMembercbu:BankingAndCorporateSegmentMember2023-01-012023-03-310000723188cbu:CertainAssetsOfCreativePlanDesignLimitedMemberus-gaap:OtherIntangibleAssetsMember2024-01-012024-03-310000723188cbu:Acquisitions2023Memberus-gaap:OtherIntangibleAssetsMember2024-01-012024-03-3100007231882024-04-3000007231882023-11-162023-11-1600007231882023-03-310000723188us-gaap:TreasuryStockCommonMember2024-01-012024-03-310000723188us-gaap:DeferredCompensationShareBasedPaymentsMember2024-01-012024-03-310000723188us-gaap:AdditionalPaidInCapitalMember2024-01-012024-03-310000723188us-gaap:TreasuryStockCommonMember2023-01-012023-03-310000723188us-gaap:DeferredCompensationShareBasedPaymentsMember2023-01-012023-03-310000723188us-gaap:AdditionalPaidInCapitalMember2023-01-012023-03-310000723188us-gaap:CommonStockMember2024-01-012024-03-310000723188us-gaap:CommonStockMember2023-01-012023-03-310000723188srt:MinimumMemberus-gaap:FairValueInputsLevel3Memberus-gaap:MeasurementInputDiscountRateMemberus-gaap:ValuationTechniqueDiscountedCashFlowMember2024-01-012024-03-310000723188srt:MaximumMemberus-gaap:FairValueInputsLevel3Memberus-gaap:MeasurementInputDiscountRateMemberus-gaap:ValuationTechniqueDiscountedCashFlowMember2024-01-012024-03-310000723188srt:MinimumMemberus-gaap:FairValueInputsLevel3Memberus-gaap:MeasurementInputDiscountRateMemberus-gaap:ValuationTechniqueDiscountedCashFlowMember2023-01-012023-12-310000723188srt:MaximumMemberus-gaap:FairValueInputsLevel3Memberus-gaap:MeasurementInputDiscountRateMemberus-gaap:ValuationTechniqueDiscountedCashFlowMember2023-01-012023-12-310000723188cbu:TotalAllowancesForCreditLossesMember2024-01-012024-03-310000723188cbu:TotalAllowancesForCreditLossesMember2023-01-012023-03-310000723188us-gaap:InvestmentInFederalHomeLoanBankStockMember2024-03-310000723188cbu:OtherEquitySecuritiesMember2024-03-310000723188cbu:FederalReserveBankStockMember2024-03-310000723188us-gaap:InvestmentInFederalHomeLoanBankStockMember2023-12-310000723188cbu:OtherEquitySecuritiesMember2023-12-310000723188cbu:FederalReserveBankStockMember2023-12-310000723188us-gaap:EstimateOfFairValueFairValueDisclosureMember2024-03-310000723188us-gaap:CarryingReportedAmountFairValueDisclosureMember2024-03-310000723188us-gaap:EstimateOfFairValueFairValueDisclosureMember2023-12-310000723188us-gaap:CarryingReportedAmountFairValueDisclosureMember2023-12-310000723188us-gaap:FairValueInputsLevel3Membercbu:MeasurementInputEstimatedCostOfDisposalOrMarketAdjustmentMembercbu:ValuationTechniqueFairValueOfCollateralMember2024-03-310000723188us-gaap:FairValueInputsLevel3Membercbu:MeasurementInputEstimatedCostOfDisposalOrMarketAdjustmentMembercbu:ValuationTechniqueFairValueOfCollateralMember2023-12-310000723188cbu:MortgageServicingRightsMember2024-03-310000723188srt:MinimumMember2024-03-310000723188cbu:TotalAllowancesForCreditLossesMember2024-03-310000723188cbu:TotalAllowancesForCreditLossesMember2023-12-310000723188cbu:TotalAllowancesForCreditLossesMember2023-03-310000723188cbu:TotalAllowancesForCreditLossesMember2022-12-310000723188us-gaap:USTreasuryAndGovernmentMember2024-03-310000723188us-gaap:MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember2024-03-310000723188us-gaap:USTreasuryAndGovernmentMember2023-12-310000723188cbu:GovernmentAgencyCollateralizedMortgageObligationsMember2023-12-310000723188us-gaap:USTreasuryAndGovernmentMember2023-03-310000723188us-gaap:FairValueInputsLevel3Memberus-gaap:MeasurementInputDiscountRateMemberus-gaap:ValuationTechniqueDiscountedCashFlowMember2024-03-310000723188us-gaap:FairValueInputsLevel3Memberus-gaap:FairValueMeasurementsNonrecurringMember2024-03-310000723188us-gaap:FairValueInputsLevel2Memberus-gaap:FairValueMeasurementsNonrecurringMember2024-03-310000723188us-gaap:FairValueInputsLevel1Memberus-gaap:FairValueMeasurementsNonrecurringMember2024-03-310000723188us-gaap:FairValueMeasurementsNonrecurringMember2024-03-310000723188us-gaap:FairValueInputsLevel3Memberus-gaap:MeasurementInputDiscountRateMemberus-gaap:ValuationTechniqueDiscountedCashFlowMember2023-12-310000723188us-gaap:FairValueInputsLevel3Memberus-gaap:FairValueMeasurementsNonrecurringMember2023-12-310000723188us-gaap:FairValueInputsLevel2Memberus-gaap:FairValueMeasurementsNonrecurringMember2023-12-310000723188us-gaap:FairValueInputsLevel1Memberus-gaap:FairValueMeasurementsNonrecurringMember2023-12-310000723188us-gaap:FairValueMeasurementsNonrecurringMember2023-12-310000723188us-gaap:FairValueInputsLevel3Membercbu:MeasurementInputAdequateCompensationMemberus-gaap:ValuationTechniqueDiscountedCashFlowMember2024-03-310000723188us-gaap:FairValueInputsLevel3Membercbu:MeasurementInputAdequateCompensationMemberus-gaap:ValuationTechniqueDiscountedCashFlowMember2023-12-3100007231882024-02-012024-02-0100007231882024-04-010000723188cbu:FringeBenefitsDesignOfMinnesotaIncMember2023-01-012023-12-310000723188cbu:CertainAssetsOfCreativePlanDesignLimitedMember2024-02-012024-02-010000723188srt:MinimumMembercbu:CertainAssetsOfFiveFinancialServiceCompaniesMember2023-01-012023-12-310000723188srt:MaximumMembercbu:CertainAssetsOfFiveFinancialServiceCompaniesMember2023-01-012023-12-310000723188cbu:CertainAssetsOfCreativePlanDesignLimitedMember2024-01-012024-03-310000723188cbu:TotalAcquisitionsMember2023-01-012023-12-310000723188cbu:OtherAcquisitionsMember2023-01-012023-12-310000723188cbu:AxiomMember2023-01-012023-12-3100007231882024-03-3100007231882023-12-3100007231882024-01-012024-03-3100007231882023-01-012023-03-31iso4217:USDxbrli:purecbu:installmentxbrli:sharesiso4217:USDxbrli:sharescbu:position

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM  10-Q

QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the quarterly period ended March 31, 2024

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: 001-13695

Graphic

(Exact name of registrant as specified in its charter)

Delaware

    

16-1213679

(State or other jurisdiction of incorporation or organization)

(I.R.S. Employer Identification No.)

5790 Widewaters Parkway, DeWitt, New York

13214-1883

(Address of principal executive offices)

(Zip Code)

(315) 445-2282

(Registrant’s telephone number, including area code)

                                                       NONE                                                      

(Former name, former address and former fiscal year, if changed since last report)

Securities registered pursuant to Section 12(b) of the Act:

Title of each class

    

Trading Symbol(s)

    

Name of each exchange on which registered

Common Stock, $1.00 par value per share

CBU

New York Stock Exchange

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  No

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  No 

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company or an 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.

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes  No 

Number of shares of common stock, par value $1.00 per share, outstanding as of the close of business on April 30, 2024: 52,771,156 shares

TABLE OF CONTENTS

Part I.

    

Financial Information

    

Page

Item 1.

Financial Statements (Unaudited)

Consolidated Statements of Condition March 31, 2024 and December 31, 2023

3

Consolidated Statements of Income Three months ended March 31, 2024 and 2023

4

Consolidated Statements of Comprehensive Income Three months ended March 31, 2024 and 2023

5

Consolidated Statements of Changes in Shareholders’ Equity Three months ended March 31, 2024 and 2023

6

Consolidated Statements of Cash Flows Three months ended March 31, 2024 and 2023

7

Notes to the Consolidated Financial Statements March 31, 2024

8

Item 2.

Management’s Discussion and Analysis of Financial Condition and Results of Operations

34

Item 3.

Quantitative and Qualitative Disclosures about Market Risk

60

Item 4.

Controls and Procedures

62

Part II.

Other Information

Item 1.

Legal Proceedings

62

Item 1A.

Risk Factors

62

Item 2.

Unregistered Sales of Equity Securities and Use of Proceeds

62

Item 3.

Defaults Upon Senior Securities

63

Item 4.

Mine Safety Disclosures

63

Item 5.

Other Information

63

Item 6.

Exhibits

64

2

Part I. Financial Information

Item 1. Financial Statements

COMMUNITY BANK SYSTEM, INC.

CONSOLIDATED STATEMENTS OF CONDITION (Unaudited)

(In Thousands, Except Share Data)

March 31, 

December 31, 

    

2024

    

2023

Assets:

  

 

  

Cash and cash equivalents

$

338,381

$

190,962

Available-for-sale investment securities, includes pledged securities that can be sold or repledged of $393,453 and $598,873, respectively (cost of $3,287,497 and $3,301,607, respectively)

 

2,863,864

 

2,919,992

Held-to-maturity securities (fair value of $1,131,615 and $1,121,816, respectively)

1,217,472

1,172,174

Equity and other securities (cost of $69,892 and $72,275, respectively)

 

70,778

 

73,146

Loans

 

9,883,500

 

9,704,598

Allowance for credit losses

 

(70,091)

 

(66,669)

Loans, net of allowance for credit losses

 

9,813,409

 

9,637,929

 

Goodwill

 

849,790

 

845,396

Core deposit intangibles, net

 

7,248

 

8,159

Other intangibles, net

 

47,401

 

44,432

Goodwill and intangible assets, net

 

904,439

 

897,987

Premises and equipment, net

170,974

173,418

Accrued interest and fees receivable

 

53,762

 

54,534

Other assets

 

425,591

 

435,611

Total assets

$

15,858,670

$

15,555,753

 

 

Liabilities:

Noninterest-bearing deposits

$

3,554,686

$

3,638,527

Interest-bearing deposits

 

9,797,336

 

9,289,594

Total deposits

 

13,352,022

 

12,928,121

Overnight borrowings

 

0

 

53,000

Securities sold under agreement to repurchase, short-term

 

287,241

 

304,595

Other Federal Home Loan Bank borrowings

 

395,122

 

407,603

Accrued interest and other liabilities

 

167,330

 

164,497

Total liabilities

 

14,201,715

 

13,857,816

 

 

Commitments and contingencies (See Note J)

 

 

Shareholders’ equity:

Preferred stock, $1.00 par value, 500,000 shares authorized, 0 shares issued

 

0

 

0

Common stock, $1.00 par value, 75,000,000 shares authorized; 54,540,107 and 54,372,292 shares issued, respectively

 

54,540

 

54,372

Additional paid-in capital

 

1,063,508

 

1,060,289

Retained earnings

 

1,205,994

 

1,188,869

Accumulated other comprehensive loss

 

(583,816)

 

(556,892)

Treasury stock, at cost (1,775,546 shares, including 100,870 shares held by deferred compensation arrangements at March 31, 2024 and 1,045,232 shares including 120,556 shares held by deferred compensation arrangements at December 31, 2023)

 

(89,027)

 

(55,592)

Deferred compensation arrangements (100,870 and 120,556 shares, respectively)

 

5,756

 

6,891

Total shareholders’ equity

 

1,656,955

 

1,697,937

Total liabilities and shareholders’ equity

$

15,858,670

$

15,555,753

See accompanying notes to consolidated financial statements (unaudited).

3

COMMUNITY BANK SYSTEM, INC.

CONSOLIDATED STATEMENTS OF INCOME (Unaudited)

(In Thousands, Except Per-Share Data)

Three Months Ended

March 31, 

    

2024

    

2023

Interest income:

 

  

 

  

Interest and fees on loans

$

127,498

$

100,362

Interest and dividends on taxable investments

 

21,902

 

21,938

Interest and dividends on nontaxable investments

 

3,259

 

3,582

Total interest income

 

152,659

 

125,882

Interest expense:

 

 

Interest on deposits

 

36,785

 

9,928

Interest on borrowings

 

8,884

 

4,924

Total interest expense

 

45,669

 

14,852

Net interest income

 

106,990

 

111,030

Provision for credit losses

 

6,148

 

3,500

Net interest income after provision for credit losses

 

100,842

 

107,530

Noninterest revenues:

 

 

Deposit service fees

 

14,251

 

12,896

Mortgage banking

345

 

275

Other banking services

 

3,656

 

3,260

Employee benefit services

 

31,698

 

29,384

Insurance services

 

11,109

 

11,522

Wealth management services

 

9,210

8,245

Loss on sales of investment securities

0

(52,329)

Gain on debt extinguishment

0

242

Unrealized gain on equity securities

 

16

0

Total noninterest revenues

 

70,285

 

13,495

Noninterest expenses:

 

 

Salaries and employee benefits

 

73,063

 

71,487

Data processing and communications

 

14,348

 

13,129

Occupancy and equipment

 

11,362

 

11,024

Amortization of intangible assets

 

3,576

 

3,667

Legal and professional fees

 

4,341

 

5,201

Business development and marketing

 

3,045

 

2,901

Litigation accrual

119

0

Acquisition expenses

35

57

Other expenses

 

8,195

 

6,586

Total noninterest expenses

 

118,084

 

114,052

Income before income taxes

 

53,043

 

6,973

Income taxes

 

12,171

 

1,175

Net income

$

40,872

$

5,798

Basic earnings per share

$

0.77

$

0.11

Diluted earnings per share

$

0.76

$

0.11

See accompanying notes to consolidated financial statements (unaudited).

4

COMMUNITY BANK SYSTEM, INC.

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited)

(In Thousands)

Three Months Ended

March 31, 

    

2024

    

2023

Pension and other post-retirement obligations:

  

 

  

Amortization of actuarial losses (gains) included in net periodic pension cost, gross

$

290

$

(549)

Tax effect

 

(71)

 

134

Amortization of actuarial losses (gains) included in net periodic pension cost, net

 

219

 

(415)

Amortization of prior service cost included in net periodic pension cost, gross

 

160

 

160

Tax effect

 

(39)

 

(39)

Amortization of prior service cost included in net periodic pension cost, net

 

121

 

121

Other comprehensive income (loss) related to pension and other post-retirement obligations, net of taxes

 

340

 

(294)

Net unrealized (losses) gains on investment securities:

 

 

Net unrealized holding (losses) gains on investment securities, gross

 

(36,066)

 

91,260

Tax effect

 

8,802

 

(22,227)

Net unrealized holding (losses) gains on investment securities, net

 

(27,264)

 

69,033

Reclassification adjustment for net losses included in net income, gross

 

0

 

52,329

Tax effect

 

0

 

(12,714)

Reclassification adjustment for net losses included in net income, net

 

0

 

39,615

Other comprehensive (loss) gain related to unrealized (losses) gains on investment securities, net of taxes

 

(27,264)

 

108,648

Other comprehensive (loss) income, net of tax

 

(26,924)

 

108,354

Net income

 

40,872

 

5,798

Comprehensive income

$

13,948

$

114,152

As of

March 31, 

December 31, 

    

2024

    

2023

Accumulated Other Comprehensive Loss by Component:

  

Unrecognized prior service cost and net actuarial losses on pension and other post-retirement obligations

  

$

(35,668)

$

(36,118)

Tax effect

  

 

8,804

 

8,914

Net unrecognized prior service cost and net actuarial losses on pension and other post-retirement obligations

  

 

(26,864)

 

(27,204)

Unrealized loss on investment securities

  

 

(735,056)

 

(698,990)

Tax effect

  

 

178,104

 

169,302

Net unrealized loss on investment securities

  

 

(556,952)

 

(529,688)

Accumulated other comprehensive loss

  

$

(583,816)

$

(556,892)

See accompanying notes to consolidated financial statements (unaudited).

5

COMMUNITY BANK SYSTEM, INC.

CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS’ EQUITY (Unaudited)

Three months ended March 31, 2024 and 2023

(In Thousands, Except Share Data)

Accumulated

Common Stock

Additional

Other

Deferred

Shares

Amount

Paid-In

Retained

Comprehensive

Treasury

Compensation

  

    

Outstanding

    

Issued

    

Capital

    

Earnings

    

Loss

    

Stock

    

Arrangements

    

Total

Balance at December 31, 2023

53,327,060

$

54,372

$

1,060,289

$

1,188,869

$

(556,892)

$

(55,592)

$

6,891

$

1,697,937

Net income

 

 

 

 

40,872

 

 

 

 

40,872

Other comprehensive loss, net of tax

 

 

 

 

 

(26,924)

 

 

 

(26,924)

Dividends declared:

 

 

 

 

 

 

 

 

Common, $0.45 per share

 

 

 

 

(23,747)

 

 

 

 

(23,747)

Common stock activity under employee stock plans

 

167,815

 

168

 

788

 

 

 

 

 

956

Stock-based compensation

 

 

 

2,378

 

 

 

 

 

2,378

Distribution of stock under deferred compensation arrangements

 

20,769

 

 

53

 

1,082

 

(1,135)

 

0

Treasury stock purchased

(751,083)

(34,517)

(34,517)

Balance at March 31, 2024

52,764,561

$

54,540

$

1,063,508

$

1,205,994

$

(583,816)

$

(89,027)

$

5,756

$

1,656,955

Balance at December 31, 2022

53,737,249

$

54,190

$

1,050,231

$

1,152,452

$

(686,439)