false
FY
0000036270
--12-31
MTB
http://fasb.org/us-gaap/2021-01-31#OtherLiabilities
http://fasb.org/us-gaap/2021-01-31#OtherLiabilities
2027-01-01
2033-12-31
http://fasb.org/us-gaap/2021-01-31#MeasurementInputComparabilityAdjustmentMember
350000
50000
40000
50000
350000
50000
40000
P7Y9M18D
P6Y10M24D
P2Y3M18D
P7M6D
P8M12D
P3Y3M18D
P10M24D
P1Y
0.00
0.80
0.10
0.00
0.98
0.16
0000036270
2021-01-01
2021-12-31
iso4217:USD
0000036270
2021-06-30
xbrli:shares
0000036270
2022-02-11
0000036270
2021-12-31
0000036270
2020-12-31
iso4217:USD
xbrli:shares
0000036270
mtb:SeriesASeriesCAndSeriesEPreferredStockMember
2021-12-31
0000036270
mtb:SeriesASeriesCAndSeriesEPreferredStockMember
2020-12-31
0000036270
mtb:SeriesFAndSeriesGPreferredStockMember
2021-12-31
0000036270
mtb:SeriesFAndSeriesGPreferredStockMember
2020-12-31
0000036270
2020-01-01
2020-12-31
0000036270
2019-01-01
2019-12-31
0000036270
us-gaap:MortgageBankingMember
2021-01-01
2021-12-31
0000036270
us-gaap:MortgageBankingMember
2020-01-01
2020-12-31
0000036270
us-gaap:MortgageBankingMember
2019-01-01
2019-12-31
0000036270
us-gaap:DepositAccountMember
2021-01-01
2021-12-31
0000036270
us-gaap:DepositAccountMember
2020-01-01
2020-12-31
0000036270
us-gaap:DepositAccountMember
2019-01-01
2019-12-31
0000036270
us-gaap:FiduciaryAndTrustMember
2021-01-01
2021-12-31
0000036270
us-gaap:FiduciaryAndTrustMember
2020-01-01
2020-12-31
0000036270
us-gaap:FiduciaryAndTrustMember
2019-01-01
2019-12-31
0000036270
2019-12-31
0000036270
2018-12-31
0000036270
us-gaap:PreferredStockMember
2018-12-31
0000036270
us-gaap:CommonStockMember
2018-12-31
0000036270
mtb:CommonStockIssuableMember
2018-12-31
0000036270
us-gaap:AdditionalPaidInCapitalMember
2018-12-31
0000036270
us-gaap:RetainedEarningsMember
2018-12-31
0000036270
us-gaap:AccumulatedOtherComprehensiveIncomeMember
2018-12-31
0000036270
us-gaap:TreasuryStockMember
2018-12-31
0000036270
us-gaap:RetainedEarningsMember
2019-01-01
2019-12-31
0000036270
us-gaap:AccumulatedOtherComprehensiveIncomeMember
2019-01-01
2019-12-31
0000036270
us-gaap:PreferredStockMember
mtb:SeriesAAndSeriesCMember
2019-01-01
2019-12-31
0000036270
mtb:SeriesAAndSeriesCMember
2019-01-01
2019-12-31
0000036270
us-gaap:PreferredStockMember
us-gaap:SeriesGPreferredStockMember
2019-01-01
2019-12-31
0000036270
us-gaap:AdditionalPaidInCapitalMember
us-gaap:SeriesGPreferredStockMember
2019-01-01
2019-12-31
0000036270
us-gaap:SeriesGPreferredStockMember
2019-01-01
2019-12-31
0000036270
us-gaap:TreasuryStockMember
2019-01-01
2019-12-31
0000036270
us-gaap:CommonStockMember
2019-01-01
2019-12-31
0000036270
mtb:CommonStockIssuableMember
2019-01-01
2019-12-31
0000036270
us-gaap:AdditionalPaidInCapitalMember
2019-01-01
2019-12-31
0000036270
us-gaap:PreferredStockMember
2019-12-31
0000036270
us-gaap:CommonStockMember
2019-12-31
0000036270
mtb:CommonStockIssuableMember
2019-12-31
0000036270
us-gaap:AdditionalPaidInCapitalMember
2019-12-31
0000036270
us-gaap:RetainedEarningsMember
2019-12-31
0000036270
us-gaap:AccumulatedOtherComprehensiveIncomeMember
2019-12-31
0000036270
us-gaap:TreasuryStockMember
2019-12-31
0000036270
us-gaap:RetainedEarningsMember
us-gaap:AccountingStandardsUpdate201613Member
2020-01-01
2020-12-31
0000036270
us-gaap:AccountingStandardsUpdate201613Member
2020-01-01
2020-12-31
0000036270
us-gaap:RetainedEarningsMember
2020-01-01
2020-12-31
0000036270
us-gaap:AccumulatedOtherComprehensiveIncomeMember
2020-01-01
2020-12-31
0000036270
us-gaap:TreasuryStockMember
2020-01-01
2020-12-31
0000036270
mtb:CommonStockIssuableMember
2020-01-01
2020-12-31
0000036270
us-gaap:AdditionalPaidInCapitalMember
2020-01-01
2020-12-31
0000036270
us-gaap:PreferredStockMember
2020-12-31
0000036270
us-gaap:CommonStockMember
2020-12-31
0000036270
mtb:CommonStockIssuableMember
2020-12-31
0000036270
us-gaap:AdditionalPaidInCapitalMember
2020-12-31
0000036270
us-gaap:RetainedEarningsMember
2020-12-31
0000036270
us-gaap:AccumulatedOtherComprehensiveIncomeMember
2020-12-31
0000036270
us-gaap:TreasuryStockMember
2020-12-31
0000036270
us-gaap:RetainedEarningsMember
2021-01-01
2021-12-31
0000036270
us-gaap:AccumulatedOtherComprehensiveIncomeMember
2021-01-01
2021-12-31
0000036270
us-gaap:PreferredStockMember
mtb:SeriesIPreferredStockMember
2021-01-01
2021-12-31
0000036270
us-gaap:AdditionalPaidInCapitalMember
mtb:SeriesIPreferredStockMember
2021-01-01
2021-12-31
0000036270
mtb:SeriesIPreferredStockMember
2021-01-01
2021-12-31
0000036270
mtb:CommonStockIssuableMember
2021-01-01
2021-12-31
0000036270
us-gaap:AdditionalPaidInCapitalMember
2021-01-01
2021-12-31
0000036270
us-gaap:TreasuryStockMember
2021-01-01
2021-12-31
0000036270
us-gaap:PreferredStockMember
2021-12-31
0000036270
us-gaap:CommonStockMember
2021-12-31
0000036270
mtb:CommonStockIssuableMember
2021-12-31
0000036270
us-gaap:AdditionalPaidInCapitalMember
2021-12-31
0000036270
us-gaap:RetainedEarningsMember
2021-12-31
0000036270
us-gaap:AccumulatedOtherComprehensiveIncomeMember
2021-12-31
0000036270
us-gaap:TreasuryStockMember
2021-12-31
0000036270
us-gaap:AccountingStandardsUpdate201409Member
2021-01-01
2021-12-31
0000036270
srt:MaximumMember
2021-01-01
2021-12-31
0000036270
srt:MinimumMember
2021-01-01
2021-12-31
xbrli:pure
0000036270
mtb:PeoplesUnitedFinancialIncMember
2021-02-22
2021-02-22
0000036270
mtb:MTMember
2021-02-22
0000036270
mtb:PeoplesUnitedFinancialIncMember
2021-12-31
0000036270
mtb:PeoplesUnitedFinancialIncMember
2021-01-01
2021-12-31
0000036270
mtb:PeoplesUnitedFinancialIncMember
us-gaap:FinancialServiceMember
2021-01-01
2021-12-31
0000036270
us-gaap:USTreasuryAndGovernmentMember
2021-12-31
0000036270
us-gaap:OtherDebtSecuritiesMember
2021-12-31
0000036270
us-gaap:USStatesAndPoliticalSubdivisionsMember
2021-12-31
0000036270
us-gaap:MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember
2021-12-31
0000036270
us-gaap:USTreasuryAndGovernmentMember
2020-12-31
0000036270
us-gaap:MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember
2020-12-31
0000036270
us-gaap:OtherDebtSecuritiesMember
2020-12-31
0000036270
us-gaap:USStatesAndPoliticalSubdivisionsMember
2020-12-31
mtb:Investment
0000036270
us-gaap:USGovernmentAgenciesDebtSecuritiesMember
2021-12-31
0000036270
us-gaap:ForeignGovernmentDebtSecuritiesMember
2021-12-31
0000036270
us-gaap:USStatesAndPoliticalSubdivisionsMember
mtb:AOrBetterCreditRatingMember
2021-12-31
0000036270
us-gaap:OtherDebtSecuritiesMember
mtb:AOrBetterCreditRatingMember
2021-12-31
0000036270
mtb:AOrBetterCreditRatingMember
2021-12-31
0000036270
us-gaap:OtherDebtSecuritiesMember
mtb:BBBCreditRatingMember
2021-12-31
0000036270
mtb:BBBCreditRatingMember
2021-12-31
0000036270
us-gaap:OtherDebtSecuritiesMember
mtb:BbMember
2021-12-31
0000036270
mtb:BbMember
2021-12-31
0000036270
us-gaap:MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember
mtb:BOrLessCreditRatingMember
2021-12-31
0000036270
mtb:BOrLessCreditRatingMember
2021-12-31
0000036270
us-gaap:MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember
mtb:NotRatedMember
2021-12-31
0000036270
us-gaap:OtherDebtSecuritiesMember
mtb:NotRatedMember
2021-12-31
0000036270
mtb:NotRatedMember
2021-12-31
0000036270
us-gaap:AvailableforsaleSecuritiesMember
2021-12-31
0000036270
us-gaap:AvailableforsaleSecuritiesMember
2020-12-31
0000036270
mtb:CommercialFinancialLoanMember
2021-12-31
0000036270
mtb:CommercialFinancialLoanMember
2020-12-31
0000036270
us-gaap:CommercialRealEstateMember
2021-12-31
0000036270
us-gaap:CommercialRealEstateMember
2020-12-31
0000036270
us-gaap:ResidentialRealEstateMember
2021-12-31
0000036270
us-gaap:ResidentialRealEstateMember
2020-12-31
0000036270
mtb:ConsumerRealEstateMember
2021-12-31
0000036270
mtb:ConsumerRealEstateMember
2020-12-31
0000036270
mtb:CommercialLeaseMember
2021-12-31
0000036270
mtb:CommercialLeaseMember
2020-12-31
0000036270
us-gaap:ResidentialMortgageMember
us-gaap:ResidentialPortfolioSegmentMember
2021-12-31
0000036270
us-gaap:ResidentialMortgageMember
us-gaap:ResidentialPortfolioSegmentMember
2020-12-31
0000036270
us-gaap:RealEstateLoanMember
us-gaap:ResidentialPortfolioSegmentMember
2021-12-31
0000036270
us-gaap:RealEstateLoanMember
us-gaap:ResidentialPortfolioSegmentMember
2020-12-31
0000036270
mtb:DirectorAndCertainOfficersMember
2021-01-01
2021-12-31
0000036270
mtb:DirectorAndCertainOfficersMember
2021-12-31
0000036270
mtb:DirectorAndCertainOfficersMember
2020-12-31
0000036270
mtb:CommercialLoansAndLeasesMember
2021-12-31
0000036270
us-gaap:CommercialRealEstatePortfolioSegmentMember
2021-12-31
0000036270
us-gaap:ResidentialMortgageMember
2021-12-31
0000036270
us-gaap:HomeEquityMember
2021-12-31
0000036270
mtb:OtherConsumerLoansMember
2021-12-31
0000036270
mtb:CommercialFinancialLeasingMember
us-gaap:FinancialAssetNotPastDueMember
2021-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
us-gaap:FinancialAssetNotPastDueMember
2021-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
us-gaap:FinancialAssetNotPastDueMember
2021-12-31
0000036270
mtb:OtherCommercialConstructionMember
us-gaap:FinancialAssetNotPastDueMember
2021-12-31
0000036270
mtb:ResidentialRealEstateExcludingAltAMember
us-gaap:FinancialAssetNotPastDueMember
2021-12-31
0000036270
mtb:ResidentialLimitedDocumentationMember
us-gaap:FinancialAssetNotPastDueMember
2021-12-31
0000036270
mtb:HomeEquityLinesAndLoansMember
us-gaap:FinancialAssetNotPastDueMember
2021-12-31
0000036270
mtb:RecreationalFinanceMember
us-gaap:FinancialAssetNotPastDueMember
2021-12-31
0000036270
us-gaap:AutomobileLoanMember
us-gaap:FinancialAssetNotPastDueMember
2021-12-31
0000036270
mtb:OtherLoansMember
us-gaap:FinancialAssetNotPastDueMember
2021-12-31
0000036270
us-gaap:FinancialAssetNotPastDueMember
2021-12-31
0000036270
mtb:CommercialFinancialLeasingMember
2021-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
2021-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
2021-12-31
0000036270
mtb:OtherCommercialConstructionMember
2021-12-31
0000036270
mtb:ResidentialRealEstateExcludingAltAMember
2021-12-31
0000036270
mtb:ResidentialLimitedDocumentationMember
2021-12-31
0000036270
mtb:HomeEquityLinesAndLoansMember
2021-12-31
0000036270
mtb:RecreationalFinanceMember
2021-12-31
0000036270
us-gaap:AutomobileLoanMember
2021-12-31
0000036270
mtb:OtherLoansMember
2021-12-31
0000036270
mtb:CommercialFinancialLeasingMember
us-gaap:FinancialAssetNotPastDueMember
2020-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
us-gaap:FinancialAssetNotPastDueMember
2020-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
us-gaap:FinancialAssetNotPastDueMember
2020-12-31
0000036270
mtb:OtherCommercialConstructionMember
us-gaap:FinancialAssetNotPastDueMember
2020-12-31
0000036270
mtb:ResidentialRealEstateExcludingAltAMember
us-gaap:FinancialAssetNotPastDueMember
2020-12-31
0000036270
mtb:ResidentialLimitedDocumentationMember
us-gaap:FinancialAssetNotPastDueMember
2020-12-31
0000036270
mtb:HomeEquityLinesAndLoansMember
us-gaap:FinancialAssetNotPastDueMember
2020-12-31
0000036270
mtb:RecreationalFinanceMember
us-gaap:FinancialAssetNotPastDueMember
2020-12-31
0000036270
us-gaap:AutomobileLoanMember
us-gaap:FinancialAssetNotPastDueMember
2020-12-31
0000036270
mtb:OtherLoansMember
us-gaap:FinancialAssetNotPastDueMember
2020-12-31
0000036270
us-gaap:FinancialAssetNotPastDueMember
2020-12-31
0000036270
mtb:CommercialFinancialLeasingMember
2020-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
2020-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
2020-12-31
0000036270
mtb:OtherCommercialConstructionMember
2020-12-31
0000036270
mtb:ResidentialRealEstateExcludingAltAMember
2020-12-31
0000036270
mtb:ResidentialLimitedDocumentationMember
2020-12-31
0000036270
mtb:HomeEquityLinesAndLoansMember
2020-12-31
0000036270
mtb:RecreationalFinanceMember
2020-12-31
0000036270
us-gaap:AutomobileLoanMember
2020-12-31
0000036270
mtb:OtherLoansMember
2020-12-31
0000036270
mtb:ResidentialRealEstateExcludingAltAMember
mtb:COVID19Member
us-gaap:PaymentDeferralMember
2021-01-01
2021-12-31
0000036270
mtb:ResidentialLimitedDocumentationMember
mtb:COVID19Member
us-gaap:PaymentDeferralMember
2021-01-01
2021-12-31
0000036270
mtb:HomeEquityLinesAndLoansMember
mtb:COVID19Member
us-gaap:PaymentDeferralMember
2021-01-01
2021-12-31
0000036270
mtb:RecreationalFinanceMember
mtb:COVID19Member
us-gaap:PaymentDeferralMember
2021-01-01
2021-12-31
0000036270
us-gaap:AutomobileLoanMember
mtb:COVID19Member
us-gaap:PaymentDeferralMember
2021-01-01
2021-12-31
0000036270
mtb:OtherLoansMember
mtb:COVID19Member
us-gaap:PaymentDeferralMember
2021-01-01
2021-12-31
0000036270
mtb:COVID19Member
us-gaap:PaymentDeferralMember
2021-01-01
2021-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:COVID19Member
us-gaap:PaymentDeferralMember
2020-01-01
2020-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
mtb:COVID19Member
us-gaap:PaymentDeferralMember
2020-01-01
2020-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
mtb:COVID19Member
us-gaap:PaymentDeferralMember
2020-01-01
2020-12-31
0000036270
mtb:OtherCommercialConstructionMember
mtb:COVID19Member
us-gaap:PaymentDeferralMember
2020-01-01
2020-12-31
0000036270
mtb:ResidentialRealEstateExcludingAltAMember
mtb:COVID19Member
us-gaap:PaymentDeferralMember
2020-01-01
2020-12-31
0000036270
mtb:ResidentialLimitedDocumentationMember
mtb:COVID19Member
us-gaap:PaymentDeferralMember
2020-01-01
2020-12-31
0000036270
mtb:HomeEquityLinesAndLoansMember
mtb:COVID19Member
us-gaap:PaymentDeferralMember
2020-01-01
2020-12-31
0000036270
mtb:RecreationalFinanceMember
mtb:COVID19Member
us-gaap:PaymentDeferralMember
2020-01-01
2020-12-31
0000036270
us-gaap:AutomobileLoanMember
mtb:COVID19Member
us-gaap:PaymentDeferralMember
2020-01-01
2020-12-31
0000036270
mtb:OtherLoansMember
mtb:COVID19Member
us-gaap:PaymentDeferralMember
2020-01-01
2020-12-31
0000036270
mtb:COVID19Member
us-gaap:PaymentDeferralMember
2020-01-01
2020-12-31
0000036270
mtb:GovernmentGuaranteedLoansMember
mtb:COVID19Member
us-gaap:PaymentDeferralMember
2021-01-01
2021-12-31
0000036270
mtb:GovernmentGuaranteedLoansMember
mtb:COVID19Member
us-gaap:PaymentDeferralMember
2020-01-01
2020-12-31
mtb:Modification
0000036270
mtb:CommercialFinancialLeasingMember
2021-01-01
2021-12-31
0000036270
us-gaap:CommercialRealEstatePortfolioSegmentMember
2021-01-01
2021-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
2021-01-01
2021-12-31
0000036270
mtb:OtherCommercialConstructionMember
2021-01-01
2021-12-31
0000036270
mtb:ResidentialRealEstateExcludingAltAMember
2021-01-01
2021-12-31
0000036270
mtb:ResidentialLimitedDocumentationMember
2021-01-01
2021-12-31
0000036270
mtb:HomeEquityLinesAndLoansMember
2021-01-01
2021-12-31
0000036270
mtb:RecreationalFinanceMember
2021-01-01
2021-12-31
0000036270
us-gaap:AutomobileLoanMember
2021-01-01
2021-12-31
0000036270
mtb:OtherLoansMember
2021-01-01
2021-12-31
0000036270
mtb:CommercialFinancialLeasingMember
2020-01-01
2020-12-31
0000036270
us-gaap:CommercialRealEstatePortfolioSegmentMember
2020-01-01
2020-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
2020-01-01
2020-12-31
0000036270
mtb:OtherCommercialConstructionMember
2020-01-01
2020-12-31
0000036270
mtb:ResidentialRealEstateExcludingAltAMember
2020-01-01
2020-12-31
0000036270
mtb:ResidentialLimitedDocumentationMember
2020-01-01
2020-12-31
0000036270
mtb:HomeEquityLinesAndLoansMember
2020-01-01
2020-12-31
0000036270
mtb:RecreationalFinanceMember
2020-01-01
2020-12-31
0000036270
us-gaap:AutomobileLoanMember
2020-01-01
2020-12-31
0000036270
mtb:OtherLoansMember
2020-01-01
2020-12-31
0000036270
us-gaap:PaymentDeferralMember
mtb:CommercialFinancialLeasingMember
2021-01-01
2021-12-31
0000036270
us-gaap:PaymentDeferralMember
us-gaap:CommercialRealEstatePortfolioSegmentMember
2021-01-01
2021-12-31
0000036270
us-gaap:PaymentDeferralMember
mtb:ResidentialBuilderAndDeveloperMember
2021-01-01
2021-12-31
0000036270
us-gaap:PaymentDeferralMember
mtb:OtherCommercialConstructionMember
2021-01-01
2021-12-31
0000036270
us-gaap:PaymentDeferralMember
mtb:ResidentialRealEstateExcludingAltAMember
2021-01-01
2021-12-31
0000036270
us-gaap:PaymentDeferralMember
mtb:ResidentialLimitedDocumentationMember
2021-01-01
2021-12-31
0000036270
us-gaap:PaymentDeferralMember
mtb:HomeEquityLinesAndLoansMember
2021-01-01
2021-12-31
0000036270
us-gaap:PaymentDeferralMember
mtb:RecreationalFinanceMember
2021-01-01
2021-12-31
0000036270
us-gaap:PaymentDeferralMember
us-gaap:AutomobileLoanMember
2021-01-01
2021-12-31
0000036270
us-gaap:PaymentDeferralMember
mtb:OtherLoansMember
2021-01-01
2021-12-31
0000036270
us-gaap:PaymentDeferralMember
2021-01-01
2021-12-31
0000036270
us-gaap:PaymentDeferralMember
mtb:CommercialFinancialLeasingMember
2020-01-01
2020-12-31
0000036270
us-gaap:PaymentDeferralMember
us-gaap:CommercialRealEstatePortfolioSegmentMember
2020-01-01
2020-12-31
0000036270
us-gaap:PaymentDeferralMember
mtb:OtherCommercialConstructionMember
2020-01-01
2020-12-31
0000036270
us-gaap:PaymentDeferralMember
mtb:ResidentialRealEstateExcludingAltAMember
2020-01-01
2020-12-31
0000036270
us-gaap:PaymentDeferralMember
mtb:ResidentialLimitedDocumentationMember
2020-01-01
2020-12-31
0000036270
us-gaap:PaymentDeferralMember
mtb:HomeEquityLinesAndLoansMember
2020-01-01
2020-12-31
0000036270
us-gaap:PaymentDeferralMember
mtb:RecreationalFinanceMember
2020-01-01
2020-12-31
0000036270
us-gaap:PaymentDeferralMember
us-gaap:AutomobileLoanMember
2020-01-01
2020-12-31
0000036270
us-gaap:PaymentDeferralMember
mtb:OtherLoansMember
2020-01-01
2020-12-31
0000036270
us-gaap:PaymentDeferralMember
2020-01-01
2020-12-31
0000036270
us-gaap:ContractualInterestRateReductionMember
mtb:CommercialFinancialLeasingMember
2020-01-01
2020-12-31
0000036270
us-gaap:ContractualInterestRateReductionMember
us-gaap:CommercialRealEstatePortfolioSegmentMember
2020-01-01
2020-12-31
0000036270
us-gaap:ContractualInterestRateReductionMember
2020-01-01
2020-12-31
0000036270
mtb:OtherModificationsMember
mtb:CommercialFinancialLeasingMember
2021-01-01
2021-12-31
0000036270
mtb:OtherModificationsMember
us-gaap:CommercialRealEstatePortfolioSegmentMember
2021-01-01
2021-12-31
0000036270
mtb:OtherModificationsMember
2021-01-01
2021-12-31
0000036270
mtb:OtherModificationsMember
mtb:CommercialFinancialLeasingMember
2020-01-01
2020-12-31
0000036270
mtb:OtherModificationsMember
us-gaap:CommercialRealEstatePortfolioSegmentMember
2020-01-01
2020-12-31
0000036270
mtb:OtherModificationsMember
2020-01-01
2020-12-31
0000036270
mtb:CombinationOfConcessionTypesMember
mtb:CommercialFinancialLeasingMember
2021-01-01
2021-12-31
0000036270
mtb:CombinationOfConcessionTypesMember
us-gaap:CommercialRealEstatePortfolioSegmentMember
2021-01-01
2021-12-31
0000036270
mtb:CombinationOfConcessionTypesMember
mtb:ResidentialRealEstateExcludingAltAMember
2021-01-01
2021-12-31
0000036270
mtb:CombinationOfConcessionTypesMember
mtb:HomeEquityLinesAndLoansMember
2021-01-01
2021-12-31
0000036270
mtb:CombinationOfConcessionTypesMember
us-gaap:AutomobileLoanMember
2021-01-01
2021-12-31
0000036270
mtb:CombinationOfConcessionTypesMember
2021-01-01
2021-12-31
0000036270
mtb:CombinationOfConcessionTypesMember
mtb:CommercialFinancialLeasingMember
2020-01-01
2020-12-31
0000036270
mtb:CombinationOfConcessionTypesMember
us-gaap:CommercialRealEstatePortfolioSegmentMember
2020-01-01
2020-12-31
0000036270
mtb:CombinationOfConcessionTypesMember
mtb:ResidentialBuilderAndDeveloperMember
2020-01-01
2020-12-31
0000036270
mtb:CombinationOfConcessionTypesMember
mtb:ResidentialRealEstateExcludingAltAMember
2020-01-01
2020-12-31
0000036270
mtb:CombinationOfConcessionTypesMember
mtb:ResidentialLimitedDocumentationMember
2020-01-01
2020-12-31
0000036270
mtb:CombinationOfConcessionTypesMember
mtb:HomeEquityLinesAndLoansMember
2020-01-01
2020-12-31
0000036270
mtb:CombinationOfConcessionTypesMember
mtb:RecreationalFinanceMember
2020-01-01
2020-12-31
0000036270
mtb:CombinationOfConcessionTypesMember
us-gaap:AutomobileLoanMember
2020-01-01
2020-12-31
0000036270
mtb:CombinationOfConcessionTypesMember
mtb:OtherLoansMember
2020-01-01
2020-12-31
0000036270
mtb:CombinationOfConcessionTypesMember
2020-01-01
2020-12-31
0000036270
mtb:CommercialFinancialLeasingMember
2019-01-01
2019-12-31
0000036270
us-gaap:CommercialRealEstatePortfolioSegmentMember
2019-01-01
2019-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
2019-01-01
2019-12-31
0000036270
mtb:OtherCommercialConstructionMember
2019-01-01
2019-12-31
0000036270
mtb:ResidentialRealEstateExcludingAltAMember
2019-01-01
2019-12-31
0000036270
mtb:ResidentialLimitedDocumentationMember
2019-01-01
2019-12-31
0000036270
mtb:HomeEquityLinesAndLoansMember
2019-01-01
2019-12-31
0000036270
mtb:RecreationalFinanceMember
2019-01-01
2019-12-31
0000036270
us-gaap:AutomobileLoanMember
2019-01-01
2019-12-31
0000036270
us-gaap:PaymentDeferralMember
mtb:CommercialFinancialLeasingMember
2019-01-01
2019-12-31
0000036270
us-gaap:PaymentDeferralMember
us-gaap:CommercialRealEstatePortfolioSegmentMember
2019-01-01
2019-12-31
0000036270
us-gaap:PaymentDeferralMember
mtb:ResidentialBuilderAndDeveloperMember
2019-01-01
2019-12-31
0000036270
us-gaap:PaymentDeferralMember
mtb:ResidentialRealEstateExcludingAltAMember
2019-01-01
2019-12-31
0000036270
us-gaap:PaymentDeferralMember
mtb:ResidentialLimitedDocumentationMember
2019-01-01
2019-12-31
0000036270
us-gaap:PaymentDeferralMember
mtb:HomeEquityLinesAndLoansMember
2019-01-01
2019-12-31
0000036270
us-gaap:PaymentDeferralMember
mtb:RecreationalFinanceMember
2019-01-01
2019-12-31
0000036270
us-gaap:PaymentDeferralMember
us-gaap:AutomobileLoanMember
2019-01-01
2019-12-31
0000036270
us-gaap:PaymentDeferralMember
2019-01-01
2019-12-31
0000036270
mtb:CombinationOfConcessionTypesMember
mtb:CommercialFinancialLeasingMember
2019-01-01
2019-12-31
0000036270
mtb:CombinationOfConcessionTypesMember
us-gaap:CommercialRealEstatePortfolioSegmentMember
2019-01-01
2019-12-31
0000036270
mtb:CombinationOfConcessionTypesMember
mtb:OtherCommercialConstructionMember
2019-01-01
2019-12-31
0000036270
mtb:CombinationOfConcessionTypesMember
mtb:ResidentialRealEstateExcludingAltAMember
2019-01-01
2019-12-31
0000036270
mtb:CombinationOfConcessionTypesMember
mtb:ResidentialLimitedDocumentationMember
2019-01-01
2019-12-31
0000036270
mtb:CombinationOfConcessionTypesMember
mtb:HomeEquityLinesAndLoansMember
2019-01-01
2019-12-31
0000036270
mtb:CombinationOfConcessionTypesMember
us-gaap:AutomobileLoanMember
2019-01-01
2019-12-31
0000036270
mtb:CombinationOfConcessionTypesMember
2019-01-01
2019-12-31
0000036270
mtb:PurchasedImpairedMember
2018-12-31
0000036270
mtb:OtherAcquiredLoansMember
2018-12-31
0000036270
mtb:PurchasedImpairedMember
2019-01-01
2019-12-31
0000036270
mtb:OtherAcquiredLoansMember
2019-01-01
2019-12-31
0000036270
mtb:PurchasedImpairedMember
2019-12-31
0000036270
mtb:OtherAcquiredLoansMember
2019-12-31
0000036270
mtb:CommercialFinancialLeasingMember
2020-12-31
0000036270
us-gaap:CommercialRealEstatePortfolioSegmentMember
2020-12-31
0000036270
us-gaap:ResidentialPortfolioSegmentMember
2020-12-31
0000036270
us-gaap:ConsumerPortfolioSegmentMember
2020-12-31
0000036270
mtb:CommercialFinancialLeasingMember
2021-01-01
2021-12-31
0000036270
us-gaap:CommercialRealEstatePortfolioSegmentMember
2021-01-01
2021-12-31
0000036270
us-gaap:ResidentialPortfolioSegmentMember
2021-01-01
2021-12-31
0000036270
us-gaap:ConsumerPortfolioSegmentMember
2021-01-01
2021-12-31
0000036270
mtb:CommercialFinancialLeasingMember
2021-12-31
0000036270
us-gaap:ResidentialPortfolioSegmentMember
2021-12-31
0000036270
us-gaap:ConsumerPortfolioSegmentMember
2021-12-31
0000036270
mtb:CommercialFinancialLeasingMember
2019-12-31
0000036270
us-gaap:CommercialRealEstatePortfolioSegmentMember
2019-12-31
0000036270
us-gaap:ResidentialPortfolioSegmentMember
2019-12-31
0000036270
us-gaap:ConsumerPortfolioSegmentMember
2019-12-31
0000036270
us-gaap:UnallocatedFinancingReceivablesMember
2019-12-31
0000036270
mtb:CommercialFinancialLeasingMember
2020-01-01
2020-12-31
0000036270
us-gaap:CommercialRealEstatePortfolioSegmentMember
2020-01-01
2020-12-31
0000036270
us-gaap:ResidentialPortfolioSegmentMember
2020-01-01
2020-12-31
0000036270
us-gaap:ConsumerPortfolioSegmentMember
2020-01-01
2020-12-31
0000036270
us-gaap:UnallocatedFinancingReceivablesMember
2020-01-01
2020-12-31
0000036270
mtb:CommercialFinancialLeasingMember
2018-12-31
0000036270
us-gaap:CommercialRealEstatePortfolioSegmentMember
2018-12-31
0000036270
us-gaap:ResidentialPortfolioSegmentMember
2018-12-31
0000036270
us-gaap:ConsumerPortfolioSegmentMember
2018-12-31
0000036270
us-gaap:UnallocatedFinancingReceivablesMember
2018-12-31
0000036270
mtb:CommercialFinancialLeasingMember
2019-01-01
2019-12-31
0000036270
us-gaap:CommercialRealEstatePortfolioSegmentMember
2019-01-01
2019-12-31
0000036270
us-gaap:ResidentialPortfolioSegmentMember
2019-01-01
2019-12-31
0000036270
us-gaap:ConsumerPortfolioSegmentMember
2019-01-01
2019-12-31
0000036270
us-gaap:UnallocatedFinancingReceivablesMember
2019-01-01
2019-12-31
0000036270
mtb:CommercialFinancialLeasingMember
2021-01-01
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
2021-01-01
0000036270
mtb:ResidentialBuilderAndDeveloperMember
2021-01-01
0000036270
mtb:OtherCommercialConstructionMember
2021-01-01
0000036270
mtb:ResidentialRealEstateExcludingAltAMember
2021-01-01
0000036270
mtb:ResidentialLimitedDocumentationMember
2021-01-01
0000036270
mtb:HomeEquityLinesAndLoansMember
2021-01-01
0000036270
mtb:RecreationalFinanceMember
2021-01-01
0000036270
us-gaap:AutomobileLoanMember
2021-01-01
0000036270
mtb:OtherLoansMember
2021-01-01
0000036270
2021-01-01
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
2021-01-01
2021-12-31
0000036270
mtb:CommercialFinancialLeasingMember
2020-01-01
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
2020-01-01
0000036270
mtb:ResidentialBuilderAndDeveloperMember
2020-01-01
0000036270
mtb:OtherCommercialConstructionMember
2020-01-01
0000036270
mtb:ResidentialRealEstateExcludingAltAMember
2020-01-01
0000036270
mtb:ResidentialLimitedDocumentationMember
2020-01-01
0000036270
mtb:HomeEquityLinesAndLoansMember
2020-01-01
0000036270
mtb:RecreationalFinanceMember
2020-01-01
0000036270
us-gaap:AutomobileLoanMember
2020-01-01
0000036270
mtb:OtherLoansMember
2020-01-01
0000036270
2020-01-01
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
2020-01-01
2020-12-31
0000036270
mtb:CommercialFinancialLeasingMember
2019-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
2019-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
2019-12-31
0000036270
mtb:OtherCommercialConstructionMember
2019-12-31
0000036270
mtb:ResidentialRealEstateExcludingAltAMember
2019-12-31
0000036270
mtb:ResidentialLimitedDocumentationMember
2019-12-31
0000036270
mtb:HomeEquityLinesAndLoansMember
2019-12-31
0000036270
mtb:RecreationalFinanceMember
2019-12-31
0000036270
us-gaap:AutomobileLoanMember
2019-12-31
0000036270
mtb:OtherLoansMember
2019-12-31
0000036270
mtb:CommercialFinancialLeasingMember
2019-01-01
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
2019-01-01
0000036270
mtb:ResidentialBuilderAndDeveloperMember
2019-01-01
0000036270
mtb:OtherCommercialConstructionMember
2019-01-01
0000036270
mtb:ResidentialRealEstateExcludingAltAMember
2019-01-01
0000036270
mtb:ResidentialLimitedDocumentationMember
2019-01-01
0000036270
mtb:HomeEquityLinesAndLoansMember
2019-01-01
0000036270
mtb:RecreationalFinanceMember
2019-01-01
0000036270
us-gaap:AutomobileLoanMember
2019-01-01
0000036270
mtb:OtherLoansMember
2019-01-01
0000036270
2019-01-01
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
2019-01-01
2019-12-31
0000036270
mtb:OtherLoansMember
2019-01-01
2019-12-31
0000036270
srt:MinimumMember
mtb:CommercialLoansAndCommercialRealEstateMember
2021-12-31
0000036270
mtb:CommercialFinancialLeasingMember
us-gaap:PassMember
mtb:LongTermDebtTwoThousandTwentyOneMember
2021-12-31
0000036270
mtb:CommercialFinancialLeasingMember
us-gaap:PassMember
mtb:LongTermDebtTwoThousandTwentyMember
2021-12-31
0000036270
mtb:CommercialFinancialLeasingMember
us-gaap:PassMember
mtb:LongTermDebtTwoThousandNineteenMember
2021-12-31
0000036270
mtb:CommercialFinancialLeasingMember
us-gaap:PassMember
mtb:LongTermDebtTwoThousandEighteenMember
2021-12-31
0000036270
mtb:CommercialFinancialLeasingMember
us-gaap:PassMember
mtb:LongTermDebtTwoThousandSeventeenMember
2021-12-31
0000036270
mtb:CommercialFinancialLeasingMember
us-gaap:PassMember
mtb:LongTermDebtPriorPeriodMember
2021-12-31
0000036270
mtb:CommercialFinancialLeasingMember
us-gaap:PassMember
us-gaap:RevolvingCreditFacilityMember
2021-12-31
0000036270
mtb:CommercialFinancialLeasingMember
us-gaap:PassMember
mtb:RevolvingLoansConvertedToTermLoansMember
2021-12-31
0000036270
mtb:CommercialFinancialLeasingMember
us-gaap:PassMember
2021-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:CriticizedAccrualMember
mtb:LongTermDebtTwoThousandTwentyOneMember
2021-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:CriticizedAccrualMember
mtb:LongTermDebtTwoThousandTwentyMember
2021-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:CriticizedAccrualMember
mtb:LongTermDebtTwoThousandNineteenMember
2021-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:CriticizedAccrualMember
mtb:LongTermDebtTwoThousandEighteenMember
2021-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:CriticizedAccrualMember
mtb:LongTermDebtTwoThousandSeventeenMember
2021-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:CriticizedAccrualMember
mtb:LongTermDebtPriorPeriodMember
2021-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:CriticizedAccrualMember
us-gaap:RevolvingCreditFacilityMember
2021-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:CriticizedAccrualMember
mtb:RevolvingLoansConvertedToTermLoansMember
2021-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:CriticizedAccrualMember
2021-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:CriticizedNonaccrualMember
mtb:LongTermDebtTwoThousandTwentyOneMember
2021-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:CriticizedNonaccrualMember
mtb:LongTermDebtTwoThousandTwentyMember
2021-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:CriticizedNonaccrualMember
mtb:LongTermDebtTwoThousandNineteenMember
2021-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:CriticizedNonaccrualMember
mtb:LongTermDebtTwoThousandEighteenMember
2021-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:CriticizedNonaccrualMember
mtb:LongTermDebtTwoThousandSeventeenMember
2021-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:CriticizedNonaccrualMember
mtb:LongTermDebtPriorPeriodMember
2021-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:CriticizedNonaccrualMember
us-gaap:RevolvingCreditFacilityMember
2021-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:CriticizedNonaccrualMember
mtb:RevolvingLoansConvertedToTermLoansMember
2021-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:CriticizedNonaccrualMember
2021-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:LongTermDebtTwoThousandTwentyOneMember
2021-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:LongTermDebtTwoThousandTwentyMember
2021-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:LongTermDebtTwoThousandNineteenMember
2021-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:LongTermDebtTwoThousandEighteenMember
2021-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:LongTermDebtTwoThousandSeventeenMember
2021-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:LongTermDebtPriorPeriodMember
2021-12-31
0000036270
mtb:CommercialFinancialLeasingMember
us-gaap:RevolvingCreditFacilityMember
2021-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:RevolvingLoansConvertedToTermLoansMember
2021-12-31
0000036270
mtb:CommercialFinancialLeasingMember
2021-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
us-gaap:PassMember
mtb:LongTermDebtTwoThousandTwentyOneMember
2021-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
us-gaap:PassMember
mtb:LongTermDebtTwoThousandTwentyMember
2021-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
us-gaap:PassMember
mtb:LongTermDebtTwoThousandNineteenMember
2021-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
us-gaap:PassMember
mtb:LongTermDebtTwoThousandEighteenMember
2021-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
us-gaap:PassMember
mtb:LongTermDebtTwoThousandSeventeenMember
2021-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
us-gaap:PassMember
mtb:LongTermDebtPriorPeriodMember
2021-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
us-gaap:PassMember
us-gaap:RevolvingCreditFacilityMember
2021-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
us-gaap:PassMember
2021-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
mtb:CriticizedAccrualMember
mtb:LongTermDebtTwoThousandTwentyOneMember
2021-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
mtb:CriticizedAccrualMember
mtb:LongTermDebtTwoThousandTwentyMember
2021-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
mtb:CriticizedAccrualMember
mtb:LongTermDebtTwoThousandNineteenMember
2021-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
mtb:CriticizedAccrualMember
mtb:LongTermDebtTwoThousandEighteenMember
2021-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
mtb:CriticizedAccrualMember
mtb:LongTermDebtTwoThousandSeventeenMember
2021-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
mtb:CriticizedAccrualMember
mtb:LongTermDebtPriorPeriodMember
2021-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
mtb:CriticizedAccrualMember
us-gaap:RevolvingCreditFacilityMember
2021-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
mtb:CriticizedAccrualMember
2021-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
mtb:CriticizedNonaccrualMember
mtb:LongTermDebtTwoThousandTwentyOneMember
2021-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
mtb:CriticizedNonaccrualMember
mtb:LongTermDebtTwoThousandTwentyMember
2021-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
mtb:CriticizedNonaccrualMember
mtb:LongTermDebtTwoThousandNineteenMember
2021-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
mtb:CriticizedNonaccrualMember
mtb:LongTermDebtTwoThousandEighteenMember
2021-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
mtb:CriticizedNonaccrualMember
mtb:LongTermDebtTwoThousandSeventeenMember
2021-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
mtb:CriticizedNonaccrualMember
mtb:LongTermDebtPriorPeriodMember
2021-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
mtb:CriticizedNonaccrualMember
us-gaap:RevolvingCreditFacilityMember
2021-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
mtb:CriticizedNonaccrualMember
2021-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
mtb:LongTermDebtTwoThousandTwentyOneMember
2021-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
mtb:LongTermDebtTwoThousandTwentyMember
2021-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
mtb:LongTermDebtTwoThousandNineteenMember
2021-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
mtb:LongTermDebtTwoThousandEighteenMember
2021-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
mtb:LongTermDebtTwoThousandSeventeenMember
2021-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
mtb:LongTermDebtPriorPeriodMember
2021-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
us-gaap:RevolvingCreditFacilityMember
2021-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
2021-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
us-gaap:PassMember
mtb:LongTermDebtTwoThousandTwentyOneMember
2021-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
us-gaap:PassMember
mtb:LongTermDebtTwoThousandTwentyMember
2021-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
us-gaap:PassMember
mtb:LongTermDebtTwoThousandNineteenMember
2021-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
us-gaap:PassMember
mtb:LongTermDebtTwoThousandEighteenMember
2021-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
us-gaap:PassMember
mtb:LongTermDebtTwoThousandSeventeenMember
2021-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
us-gaap:PassMember
mtb:LongTermDebtPriorPeriodMember
2021-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
us-gaap:PassMember
us-gaap:RevolvingCreditFacilityMember
2021-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
us-gaap:PassMember
2021-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
mtb:CriticizedAccrualMember
mtb:LongTermDebtTwoThousandTwentyOneMember
2021-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
mtb:CriticizedAccrualMember
mtb:LongTermDebtTwoThousandTwentyMember
2021-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
mtb:CriticizedAccrualMember
mtb:LongTermDebtTwoThousandNineteenMember
2021-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
mtb:CriticizedAccrualMember
mtb:LongTermDebtTwoThousandEighteenMember
2021-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
mtb:CriticizedAccrualMember
mtb:LongTermDebtTwoThousandSeventeenMember
2021-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
mtb:CriticizedAccrualMember
us-gaap:RevolvingCreditFacilityMember
2021-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
mtb:CriticizedAccrualMember
2021-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
mtb:CriticizedNonaccrualMember
mtb:LongTermDebtTwoThousandNineteenMember
2021-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
mtb:CriticizedNonaccrualMember
mtb:LongTermDebtPriorPeriodMember
2021-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
mtb:CriticizedNonaccrualMember
2021-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
mtb:LongTermDebtTwoThousandTwentyOneMember
2021-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
mtb:LongTermDebtTwoThousandTwentyMember
2021-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
mtb:LongTermDebtTwoThousandNineteenMember
2021-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
mtb:LongTermDebtTwoThousandEighteenMember
2021-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
mtb:LongTermDebtTwoThousandSeventeenMember
2021-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
mtb:LongTermDebtPriorPeriodMember
2021-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
us-gaap:RevolvingCreditFacilityMember
2021-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
2021-12-31
0000036270
mtb:OtherCommercialConstructionMember
us-gaap:PassMember
mtb:LongTermDebtTwoThousandTwentyOneMember
2021-12-31
0000036270
mtb:OtherCommercialConstructionMember
us-gaap:PassMember
mtb:LongTermDebtTwoThousandTwentyMember
2021-12-31
0000036270
mtb:OtherCommercialConstructionMember
us-gaap:PassMember
mtb:LongTermDebtTwoThousandNineteenMember
2021-12-31
0000036270
mtb:OtherCommercialConstructionMember
us-gaap:PassMember
mtb:LongTermDebtTwoThousandEighteenMember
2021-12-31
0000036270
mtb:OtherCommercialConstructionMember
us-gaap:PassMember
mtb:LongTermDebtTwoThousandSeventeenMember
2021-12-31
0000036270
mtb:OtherCommercialConstructionMember
us-gaap:PassMember
mtb:LongTermDebtPriorPeriodMember
2021-12-31
0000036270
mtb:OtherCommercialConstructionMember
us-gaap:PassMember
us-gaap:RevolvingCreditFacilityMember
2021-12-31
0000036270
mtb:OtherCommercialConstructionMember
us-gaap:PassMember
2021-12-31
0000036270
mtb:OtherCommercialConstructionMember
mtb:CriticizedAccrualMember
mtb:LongTermDebtTwoThousandTwentyOneMember
2021-12-31
0000036270
mtb:OtherCommercialConstructionMember
mtb:CriticizedAccrualMember
mtb:LongTermDebtTwoThousandTwentyMember
2021-12-31
0000036270
mtb:OtherCommercialConstructionMember
mtb:CriticizedAccrualMember
mtb:LongTermDebtTwoThousandNineteenMember
2021-12-31
0000036270
mtb:OtherCommercialConstructionMember
mtb:CriticizedAccrualMember
mtb:LongTermDebtTwoThousandEighteenMember
2021-12-31
0000036270
mtb:OtherCommercialConstructionMember
mtb:CriticizedAccrualMember
mtb:LongTermDebtTwoThousandSeventeenMember
2021-12-31
0000036270
mtb:OtherCommercialConstructionMember
mtb:CriticizedAccrualMember
mtb:LongTermDebtPriorPeriodMember
2021-12-31
0000036270
mtb:OtherCommercialConstructionMember
mtb:CriticizedAccrualMember
2021-12-31
0000036270
mtb:OtherCommercialConstructionMember
mtb:CriticizedNonaccrualMember
mtb:LongTermDebtTwoThousandNineteenMember
2021-12-31
0000036270
mtb:OtherCommercialConstructionMember
mtb:CriticizedNonaccrualMember
mtb:LongTermDebtTwoThousandEighteenMember
2021-12-31
0000036270
mtb:OtherCommercialConstructionMember
mtb:CriticizedNonaccrualMember
mtb:LongTermDebtTwoThousandSeventeenMember
2021-12-31
0000036270
mtb:OtherCommercialConstructionMember
mtb:CriticizedNonaccrualMember
mtb:LongTermDebtPriorPeriodMember
2021-12-31
0000036270
mtb:OtherCommercialConstructionMember
mtb:CriticizedNonaccrualMember
us-gaap:RevolvingCreditFacilityMember
2021-12-31
0000036270
mtb:OtherCommercialConstructionMember
mtb:CriticizedNonaccrualMember
2021-12-31
0000036270
mtb:OtherCommercialConstructionMember
mtb:LongTermDebtTwoThousandTwentyOneMember
2021-12-31
0000036270
mtb:OtherCommercialConstructionMember
mtb:LongTermDebtTwoThousandTwentyMember
2021-12-31
0000036270
mtb:OtherCommercialConstructionMember
mtb:LongTermDebtTwoThousandNineteenMember
2021-12-31
0000036270
mtb:OtherCommercialConstructionMember
mtb:LongTermDebtTwoThousandEighteenMember
2021-12-31
0000036270
mtb:OtherCommercialConstructionMember
mtb:LongTermDebtTwoThousandSeventeenMember
2021-12-31
0000036270
mtb:OtherCommercialConstructionMember
mtb:LongTermDebtPriorPeriodMember
2021-12-31
0000036270
mtb:OtherCommercialConstructionMember
us-gaap:RevolvingCreditFacilityMember
2021-12-31
0000036270
mtb:OtherCommercialConstructionMember
2021-12-31
0000036270
mtb:ResidentialRealEstateExcludingAltAMember
mtb:LongTermDebtTwoThousandTwentyOneMember
us-gaap:FinancialAssetNotPastDueMember
2021-12-31
0000036270
mtb:ResidentialRealEstateExcludingAltAMember
mtb:LongTermDebtTwoThousandTwentyMember
us-gaap:FinancialAssetNotPastDueMember
2021-12-31
0000036270
mtb:ResidentialRealEstateExcludingAltAMember
mtb:LongTermDebtTwoThousandNineteenMember
us-gaap:FinancialAssetNotPastDueMember
2021-12-31
0000036270
mtb:ResidentialRealEstateExcludingAltAMember
mtb:LongTermDebtTwoThousandEighteenMember
us-gaap:FinancialAssetNotPastDueMember
2021-12-31
0000036270
mtb:ResidentialRealEstateExcludingAltAMember
mtb:LongTermDebtTwoThousandSeventeenMember
us-gaap:FinancialAssetNotPastDueMember
2021-12-31
0000036270
mtb:ResidentialRealEstateExcludingAltAMember
mtb:LongTermDebtPriorPeriodMember
us-gaap:FinancialAssetNotPastDueMember
2021-12-31
0000036270
mtb:ResidentialRealEstateExcludingAltAMember
us-gaap:RevolvingCreditFacilityMember
us-gaap:FinancialAssetNotPastDueMember
2021-12-31
0000036270
mtb:ResidentialRealEstateExcludingAltAMember
mtb:LongTermDebtTwoThousandTwentyOneMember
2021-12-31
0000036270
mtb:ResidentialRealEstateExcludingAltAMember
mtb:LongTermDebtTwoThousandTwentyMember
2021-12-31
0000036270
mtb:ResidentialRealEstateExcludingAltAMember
mtb:LongTermDebtTwoThousandNineteenMember
2021-12-31
0000036270
mtb:ResidentialRealEstateExcludingAltAMember
mtb:LongTermDebtTwoThousandEighteenMember
2021-12-31
0000036270
mtb:ResidentialRealEstateExcludingAltAMember
mtb:LongTermDebtTwoThousandSeventeenMember
2021-12-31
0000036270
mtb:ResidentialRealEstateExcludingAltAMember
mtb:LongTermDebtPriorPeriodMember
2021-12-31
0000036270
mtb:ResidentialRealEstateExcludingAltAMember
us-gaap:RevolvingCreditFacilityMember
2021-12-31
0000036270
mtb:ResidentialLimitedDocumentationMember
mtb:LongTermDebtPriorPeriodMember
us-gaap:FinancialAssetNotPastDueMember
2021-12-31
0000036270
mtb:ResidentialLimitedDocumentationMember
mtb:LongTermDebtPriorPeriodMember
2021-12-31
0000036270
mtb:HomeEquityLinesAndLoansMember
mtb:LongTermDebtTwoThousandTwentyOneMember
us-gaap:FinancialAssetNotPastDueMember
2021-12-31
0000036270
mtb:HomeEquityLinesAndLoansMember
mtb:LongTermDebtTwoThousandTwentyMember
us-gaap:FinancialAssetNotPastDueMember
2021-12-31
0000036270
mtb:HomeEquityLinesAndLoansMember
mtb:LongTermDebtTwoThousandNineteenMember
us-gaap:FinancialAssetNotPastDueMember
2021-12-31
0000036270
mtb:HomeEquityLinesAndLoansMember
mtb:LongTermDebtTwoThousandEighteenMember
us-gaap:FinancialAssetNotPastDueMember
2021-12-31
0000036270
mtb:HomeEquityLinesAndLoansMember
mtb:LongTermDebtTwoThousandSeventeenMember
us-gaap:FinancialAssetNotPastDueMember
2021-12-31
0000036270
mtb:HomeEquityLinesAndLoansMember
mtb:LongTermDebtPriorPeriodMember
us-gaap:FinancialAssetNotPastDueMember
2021-12-31
0000036270
mtb:HomeEquityLinesAndLoansMember
us-gaap:RevolvingCreditFacilityMember
us-gaap:FinancialAssetNotPastDueMember
2021-12-31
0000036270
mtb:HomeEquityLinesAndLoansMember
mtb:RevolvingLoansConvertedToTermLoansMember
us-gaap:FinancialAssetNotPastDueMember
2021-12-31
0000036270
mtb:HomeEquityLinesAndLoansMember
mtb:LongTermDebtTwoThousandEighteenMember
2021-12-31
0000036270
mtb:HomeEquityLinesAndLoansMember
mtb:LongTermDebtPriorPeriodMember
2021-12-31
0000036270
mtb:HomeEquityLinesAndLoansMember
us-gaap:RevolvingCreditFacilityMember
2021-12-31
0000036270
mtb:HomeEquityLinesAndLoansMember
mtb:RevolvingLoansConvertedToTermLoansMember
2021-12-31
0000036270
mtb:HomeEquityLinesAndLoansMember
mtb:LongTermDebtTwoThousandTwentyOneMember
2021-12-31
0000036270
mtb:HomeEquityLinesAndLoansMember
mtb:LongTermDebtTwoThousandTwentyMember
2021-12-31
0000036270
mtb:HomeEquityLinesAndLoansMember
mtb:LongTermDebtTwoThousandNineteenMember
2021-12-31
0000036270
mtb:HomeEquityLinesAndLoansMember
mtb:LongTermDebtTwoThousandSeventeenMember
2021-12-31
0000036270
mtb:RecreationalFinanceMember
mtb:LongTermDebtTwoThousandTwentyOneMember
us-gaap:FinancialAssetNotPastDueMember
2021-12-31
0000036270
mtb:RecreationalFinanceMember
mtb:LongTermDebtTwoThousandTwentyMember
us-gaap:FinancialAssetNotPastDueMember
2021-12-31
0000036270
mtb:RecreationalFinanceMember
mtb:LongTermDebtTwoThousandNineteenMember
us-gaap:FinancialAssetNotPastDueMember
2021-12-31
0000036270
mtb:RecreationalFinanceMember
mtb:LongTermDebtTwoThousandEighteenMember
us-gaap:FinancialAssetNotPastDueMember
2021-12-31
0000036270
mtb:RecreationalFinanceMember
mtb:LongTermDebtTwoThousandSeventeenMember
us-gaap:FinancialAssetNotPastDueMember
2021-12-31
0000036270
mtb:RecreationalFinanceMember
mtb:LongTermDebtPriorPeriodMember
us-gaap:FinancialAssetNotPastDueMember
2021-12-31
0000036270
mtb:RecreationalFinanceMember
mtb:LongTermDebtTwoThousandTwentyOneMember
2021-12-31
0000036270
mtb:RecreationalFinanceMember
mtb:LongTermDebtTwoThousandTwentyMember
2021-12-31
0000036270
mtb:RecreationalFinanceMember
mtb:LongTermDebtTwoThousandNineteenMember
2021-12-31
0000036270
mtb:RecreationalFinanceMember
mtb:LongTermDebtTwoThousandEighteenMember
2021-12-31
0000036270
mtb:RecreationalFinanceMember
mtb:LongTermDebtTwoThousandSeventeenMember
2021-12-31
0000036270
mtb:RecreationalFinanceMember
mtb:LongTermDebtPriorPeriodMember
2021-12-31
0000036270
us-gaap:AutomobileLoanMember
mtb:LongTermDebtTwoThousandTwentyOneMember
us-gaap:FinancialAssetNotPastDueMember
2021-12-31
0000036270
us-gaap:AutomobileLoanMember
mtb:LongTermDebtTwoThousandTwentyMember
us-gaap:FinancialAssetNotPastDueMember
2021-12-31
0000036270
us-gaap:AutomobileLoanMember
mtb:LongTermDebtTwoThousandNineteenMember
us-gaap:FinancialAssetNotPastDueMember
2021-12-31
0000036270
us-gaap:AutomobileLoanMember
mtb:LongTermDebtTwoThousandEighteenMember
us-gaap:FinancialAssetNotPastDueMember
2021-12-31
0000036270
us-gaap:AutomobileLoanMember
mtb:LongTermDebtTwoThousandSeventeenMember
us-gaap:FinancialAssetNotPastDueMember
2021-12-31
0000036270
us-gaap:AutomobileLoanMember
mtb:LongTermDebtPriorPeriodMember
us-gaap:FinancialAssetNotPastDueMember
2021-12-31
0000036270
us-gaap:AutomobileLoanMember
mtb:LongTermDebtTwoThousandTwentyOneMember
2021-12-31
0000036270
us-gaap:AutomobileLoanMember
mtb:LongTermDebtTwoThousandTwentyMember
2021-12-31
0000036270
us-gaap:AutomobileLoanMember
mtb:LongTermDebtTwoThousandNineteenMember
2021-12-31
0000036270
us-gaap:AutomobileLoanMember
mtb:LongTermDebtTwoThousandEighteenMember
2021-12-31
0000036270
us-gaap:AutomobileLoanMember
mtb:LongTermDebtTwoThousandSeventeenMember
2021-12-31
0000036270
us-gaap:AutomobileLoanMember
mtb:LongTermDebtPriorPeriodMember
2021-12-31
0000036270
mtb:OtherLoansMember
mtb:LongTermDebtTwoThousandTwentyOneMember
us-gaap:FinancialAssetNotPastDueMember
2021-12-31
0000036270
mtb:OtherLoansMember
mtb:LongTermDebtTwoThousandTwentyMember
us-gaap:FinancialAssetNotPastDueMember
2021-12-31
0000036270
mtb:OtherLoansMember
mtb:LongTermDebtTwoThousandNineteenMember
us-gaap:FinancialAssetNotPastDueMember
2021-12-31
0000036270
mtb:OtherLoansMember
mtb:LongTermDebtTwoThousandEighteenMember
us-gaap:FinancialAssetNotPastDueMember
2021-12-31
0000036270
mtb:OtherLoansMember
mtb:LongTermDebtTwoThousandSeventeenMember
us-gaap:FinancialAssetNotPastDueMember
2021-12-31
0000036270
mtb:OtherLoansMember
mtb:LongTermDebtPriorPeriodMember
us-gaap:FinancialAssetNotPastDueMember
2021-12-31
0000036270
us-gaap:RevolvingCreditFacilityMember
mtb:OtherLoansMember
us-gaap:FinancialAssetNotPastDueMember
2021-12-31
0000036270
mtb:RevolvingLoansConvertedToTermLoansMember
mtb:OtherLoansMember
us-gaap:FinancialAssetNotPastDueMember
2021-12-31
0000036270
mtb:OtherLoansMember
mtb:LongTermDebtTwoThousandTwentyOneMember
2021-12-31
0000036270
mtb:OtherLoansMember
mtb:LongTermDebtTwoThousandTwentyMember
2021-12-31
0000036270
mtb:OtherLoansMember
mtb:LongTermDebtTwoThousandNineteenMember
2021-12-31
0000036270
mtb:OtherLoansMember
mtb:LongTermDebtTwoThousandEighteenMember
2021-12-31
0000036270
mtb:OtherLoansMember
mtb:LongTermDebtTwoThousandSeventeenMember
2021-12-31
0000036270
mtb:OtherLoansMember
mtb:LongTermDebtPriorPeriodMember
2021-12-31
0000036270
us-gaap:RevolvingCreditFacilityMember
mtb:OtherLoansMember
2021-12-31
0000036270
mtb:RevolvingLoansConvertedToTermLoansMember
mtb:OtherLoansMember
2021-12-31
0000036270
mtb:LongTermDebtTwoThousandTwentyOneMember
2021-12-31
0000036270
mtb:LongTermDebtTwoThousandTwentyMember
2021-12-31
0000036270
mtb:LongTermDebtTwoThousandNineteenMember
2021-12-31
0000036270
mtb:LongTermDebtTwoThousandEighteenMember
2021-12-31
0000036270
mtb:LongTermDebtTwoThousandSeventeenMember
2021-12-31
0000036270
mtb:LongTermDebtPriorPeriodMember
2021-12-31
0000036270
us-gaap:RevolvingCreditFacilityMember
2021-12-31
0000036270
mtb:RevolvingLoansConvertedToTermLoansMember
2021-12-31
0000036270
mtb:CommercialFinancialLeasingMember
us-gaap:PassMember
mtb:LongTermDebtTwoThousandTwentyOneMember
2020-12-31
0000036270
mtb:CommercialFinancialLeasingMember
us-gaap:PassMember
mtb:LongTermDebtTwoThousandNineteenMember
2020-12-31
0000036270
mtb:CommercialFinancialLeasingMember
us-gaap:PassMember
mtb:LongTermDebtTwoThousandEighteenMember
2020-12-31
0000036270
mtb:CommercialFinancialLeasingMember
us-gaap:PassMember
mtb:LongTermDebtTwoThousandSeventeenMember
2020-12-31
0000036270
mtb:CommercialFinancialLeasingMember
us-gaap:PassMember
mtb:LongTermDebtTwoThousandSixteenMember
2020-12-31
0000036270
mtb:CommercialFinancialLeasingMember
us-gaap:PassMember
mtb:LongTermDebtPriorPeriodMember
2020-12-31
0000036270
mtb:CommercialFinancialLeasingMember
us-gaap:PassMember
us-gaap:RevolvingCreditFacilityMember
2020-12-31
0000036270
mtb:CommercialFinancialLeasingMember
us-gaap:PassMember
mtb:RevolvingLoansConvertedToTermLoansMember
2020-12-31
0000036270
mtb:CommercialFinancialLeasingMember
us-gaap:PassMember
2020-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:CriticizedAccrualMember
mtb:LongTermDebtTwoThousandTwentyOneMember
2020-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:CriticizedAccrualMember
mtb:LongTermDebtTwoThousandNineteenMember
2020-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:CriticizedAccrualMember
mtb:LongTermDebtTwoThousandEighteenMember
2020-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:CriticizedAccrualMember
mtb:LongTermDebtTwoThousandSeventeenMember
2020-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:CriticizedAccrualMember
mtb:LongTermDebtTwoThousandSixteenMember
2020-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:CriticizedAccrualMember
mtb:LongTermDebtPriorPeriodMember
2020-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:CriticizedAccrualMember
us-gaap:RevolvingCreditFacilityMember
2020-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:CriticizedAccrualMember
mtb:RevolvingLoansConvertedToTermLoansMember
2020-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:CriticizedAccrualMember
2020-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:CriticizedNonaccrualMember
mtb:LongTermDebtTwoThousandTwentyOneMember
2020-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:CriticizedNonaccrualMember
mtb:LongTermDebtTwoThousandNineteenMember
2020-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:CriticizedNonaccrualMember
mtb:LongTermDebtTwoThousandEighteenMember
2020-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:CriticizedNonaccrualMember
mtb:LongTermDebtTwoThousandSeventeenMember
2020-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:CriticizedNonaccrualMember
mtb:LongTermDebtTwoThousandSixteenMember
2020-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:CriticizedNonaccrualMember
mtb:LongTermDebtPriorPeriodMember
2020-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:CriticizedNonaccrualMember
us-gaap:RevolvingCreditFacilityMember
2020-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:CriticizedNonaccrualMember
mtb:RevolvingLoansConvertedToTermLoansMember
2020-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:CriticizedNonaccrualMember
2020-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:LongTermDebtTwoThousandTwentyOneMember
2020-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:LongTermDebtTwoThousandNineteenMember
2020-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:LongTermDebtTwoThousandEighteenMember
2020-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:LongTermDebtTwoThousandSeventeenMember
2020-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:LongTermDebtTwoThousandSixteenMember
2020-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:LongTermDebtPriorPeriodMember
2020-12-31
0000036270
mtb:CommercialFinancialLeasingMember
us-gaap:RevolvingCreditFacilityMember
2020-12-31
0000036270
mtb:CommercialFinancialLeasingMember
mtb:RevolvingLoansConvertedToTermLoansMember
2020-12-31
0000036270
mtb:CommercialFinancialLeasingMember
2020-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
us-gaap:PassMember
mtb:LongTermDebtTwoThousandTwentyOneMember
2020-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
us-gaap:PassMember
mtb:LongTermDebtTwoThousandNineteenMember
2020-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
us-gaap:PassMember
mtb:LongTermDebtTwoThousandEighteenMember
2020-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
us-gaap:PassMember
mtb:LongTermDebtTwoThousandSeventeenMember
2020-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
us-gaap:PassMember
mtb:LongTermDebtTwoThousandSixteenMember
2020-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
us-gaap:PassMember
mtb:LongTermDebtPriorPeriodMember
2020-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
us-gaap:PassMember
us-gaap:RevolvingCreditFacilityMember
2020-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
us-gaap:PassMember
2020-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
mtb:CriticizedAccrualMember
mtb:LongTermDebtTwoThousandTwentyOneMember
2020-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
mtb:CriticizedAccrualMember
mtb:LongTermDebtTwoThousandNineteenMember
2020-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
mtb:CriticizedAccrualMember
mtb:LongTermDebtTwoThousandEighteenMember
2020-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
mtb:CriticizedAccrualMember
mtb:LongTermDebtTwoThousandSeventeenMember
2020-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
mtb:CriticizedAccrualMember
mtb:LongTermDebtTwoThousandSixteenMember
2020-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
mtb:CriticizedAccrualMember
mtb:LongTermDebtPriorPeriodMember
2020-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
mtb:CriticizedAccrualMember
us-gaap:RevolvingCreditFacilityMember
2020-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
mtb:CriticizedAccrualMember
2020-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
mtb:CriticizedNonaccrualMember
mtb:LongTermDebtTwoThousandTwentyOneMember
2020-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
mtb:CriticizedNonaccrualMember
mtb:LongTermDebtTwoThousandNineteenMember
2020-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
mtb:CriticizedNonaccrualMember
mtb:LongTermDebtTwoThousandEighteenMember
2020-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
mtb:CriticizedNonaccrualMember
mtb:LongTermDebtTwoThousandSeventeenMember
2020-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
mtb:CriticizedNonaccrualMember
mtb:LongTermDebtTwoThousandSixteenMember
2020-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
mtb:CriticizedNonaccrualMember
mtb:LongTermDebtPriorPeriodMember
2020-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
mtb:CriticizedNonaccrualMember
us-gaap:RevolvingCreditFacilityMember
2020-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
mtb:CriticizedNonaccrualMember
2020-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
mtb:LongTermDebtTwoThousandTwentyOneMember
2020-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
mtb:LongTermDebtTwoThousandNineteenMember
2020-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
mtb:LongTermDebtTwoThousandEighteenMember
2020-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
mtb:LongTermDebtTwoThousandSeventeenMember
2020-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
mtb:LongTermDebtTwoThousandSixteenMember
2020-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
mtb:LongTermDebtPriorPeriodMember
2020-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
us-gaap:RevolvingCreditFacilityMember
2020-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
2020-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
us-gaap:PassMember
mtb:LongTermDebtTwoThousandTwentyOneMember
2020-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
us-gaap:PassMember
mtb:LongTermDebtTwoThousandNineteenMember
2020-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
us-gaap:PassMember
mtb:LongTermDebtTwoThousandEighteenMember
2020-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
us-gaap:PassMember
mtb:LongTermDebtTwoThousandSeventeenMember
2020-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
us-gaap:PassMember
mtb:LongTermDebtTwoThousandSixteenMember
2020-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
us-gaap:PassMember
mtb:LongTermDebtPriorPeriodMember
2020-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
us-gaap:PassMember
us-gaap:RevolvingCreditFacilityMember
2020-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
us-gaap:PassMember
2020-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
mtb:CriticizedAccrualMember
mtb:LongTermDebtTwoThousandTwentyOneMember
2020-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
mtb:CriticizedAccrualMember
mtb:LongTermDebtTwoThousandNineteenMember
2020-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
mtb:CriticizedAccrualMember
mtb:LongTermDebtTwoThousandEighteenMember
2020-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
mtb:CriticizedAccrualMember
mtb:LongTermDebtTwoThousandSeventeenMember
2020-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
mtb:CriticizedAccrualMember
mtb:LongTermDebtPriorPeriodMember
2020-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
mtb:CriticizedAccrualMember
us-gaap:RevolvingCreditFacilityMember
2020-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
mtb:CriticizedAccrualMember
2020-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
mtb:CriticizedNonaccrualMember
mtb:LongTermDebtTwoThousandNineteenMember
2020-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
mtb:CriticizedNonaccrualMember
mtb:LongTermDebtPriorPeriodMember
2020-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
mtb:CriticizedNonaccrualMember
2020-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
mtb:LongTermDebtTwoThousandTwentyOneMember
2020-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
mtb:LongTermDebtTwoThousandNineteenMember
2020-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
mtb:LongTermDebtTwoThousandEighteenMember
2020-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
mtb:LongTermDebtTwoThousandSeventeenMember
2020-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
mtb:LongTermDebtTwoThousandSixteenMember
2020-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
mtb:LongTermDebtPriorPeriodMember
2020-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
us-gaap:RevolvingCreditFacilityMember
2020-12-31
0000036270
mtb:ResidentialBuilderAndDeveloperMember
2020-12-31
0000036270
mtb:OtherCommercialConstructionMember
us-gaap:PassMember
mtb:LongTermDebtTwoThousandTwentyOneMember
2020-12-31
0000036270
mtb:OtherCommercialConstructionMember
us-gaap:PassMember
mtb:LongTermDebtTwoThousandNineteenMember
2020-12-31
0000036270
mtb:OtherCommercialConstructionMember
us-gaap:PassMember
mtb:LongTermDebtTwoThousandEighteenMember
2020-12-31
0000036270
mtb:OtherCommercialConstructionMember
us-gaap:PassMember
mtb:LongTermDebtTwoThousandSeventeenMember
2020-12-31
0000036270
mtb:OtherCommercialConstructionMember
us-gaap:PassMember
mtb:LongTermDebtTwoThousandSixteenMember
2020-12-31
0000036270
mtb:OtherCommercialConstructionMember
us-gaap:PassMember
mtb:LongTermDebtPriorPeriodMember
2020-12-31
0000036270
mtb:OtherCommercialConstructionMember
us-gaap:PassMember
us-gaap:RevolvingCreditFacilityMember
2020-12-31
0000036270
mtb:OtherCommercialConstructionMember
us-gaap:PassMember
2020-12-31
0000036270
mtb:OtherCommercialConstructionMember
mtb:CriticizedAccrualMember
mtb:LongTermDebtTwoThousandTwentyOneMember
2020-12-31
0000036270
mtb:OtherCommercialConstructionMember
mtb:CriticizedAccrualMember
mtb:LongTermDebtTwoThousandNineteenMember
2020-12-31
0000036270
mtb:OtherCommercialConstructionMember
mtb:CriticizedAccrualMember
mtb:LongTermDebtTwoThousandEighteenMember
2020-12-31
0000036270
mtb:OtherCommercialConstructionMember
mtb:CriticizedAccrualMember
mtb:LongTermDebtTwoThousandSeventeenMember
2020-12-31
0000036270
mtb:OtherCommercialConstructionMember
mtb:CriticizedAccrualMember
mtb:LongTermDebtTwoThousandSixteenMember
2020-12-31
0000036270
mtb:OtherCommercialConstructionMember
mtb:CriticizedAccrualMember
mtb:LongTermDebtPriorPeriodMember
2020-12-31
0000036270
mtb:OtherCommercialConstructionMember
mtb:CriticizedAccrualMember
2020-12-31
0000036270
mtb:OtherCommercialConstructionMember
mtb:CriticizedNonaccrualMember
mtb:LongTermDebtTwoThousandTwentyOneMember
2020-12-31
0000036270
mtb:OtherCommercialConstructionMember
mtb:CriticizedNonaccrualMember
mtb:LongTermDebtTwoThousandNineteenMember
2020-12-31
0000036270
mtb:OtherCommercialConstructionMember
mtb:CriticizedNonaccrualMember
mtb:LongTermDebtTwoThousandEighteenMember
2020-12-31
0000036270
mtb:OtherCommercialConstructionMember
mtb:CriticizedNonaccrualMember
mtb:LongTermDebtTwoThousandSeventeenMember
2020-12-31
0000036270
mtb:OtherCommercialConstructionMember
mtb:CriticizedNonaccrualMember
mtb:LongTermDebtTwoThousandSixteenMember
2020-12-31
0000036270
mtb:OtherCommercialConstructionMember
mtb:CriticizedNonaccrualMember
mtb:LongTermDebtPriorPeriodMember
2020-12-31
0000036270
mtb:OtherCommercialConstructionMember
mtb:CriticizedNonaccrualMember
us-gaap:RevolvingCreditFacilityMember
2020-12-31
0000036270
mtb:OtherCommercialConstructionMember
mtb:CriticizedNonaccrualMember
2020-12-31
0000036270
mtb:OtherCommercialConstructionMember
mtb:LongTermDebtTwoThousandTwentyOneMember
2020-12-31
0000036270
mtb:OtherCommercialConstructionMember
mtb:LongTermDebtTwoThousandNineteenMember
2020-12-31
0000036270
mtb:OtherCommercialConstructionMember
mtb:LongTermDebtTwoThousandEighteenMember
2020-12-31
0000036270
mtb:OtherCommercialConstructionMember
mtb:LongTermDebtTwoThousandSeventeenMember
2020-12-31
0000036270
mtb:OtherCommercialConstructionMember
mtb:LongTermDebtTwoThousandSixteenMember
2020-12-31
0000036270
mtb:OtherCommercialConstructionMember
mtb:LongTermDebtPriorPeriodMember
2020-12-31
0000036270
mtb:OtherCommercialConstructionMember
us-gaap:RevolvingCreditFacilityMember
2020-12-31
0000036270
mtb:OtherCommercialConstructionMember
2020-12-31
0000036270
mtb:ResidentialRealEstateExcludingAltAMember
mtb:LongTermDebtTwoThousandTwentyMember
us-gaap:FinancialAssetNotPastDueMember
2020-12-31
0000036270
mtb:ResidentialRealEstateExcludingAltAMember
mtb:LongTermDebtTwoThousandNineteenMember
us-gaap:FinancialAssetNotPastDueMember
2020-12-31
0000036270
mtb:ResidentialRealEstateExcludingAltAMember
mtb:LongTermDebtTwoThousandEighteenMember
us-gaap:FinancialAssetNotPastDueMember
2020-12-31
0000036270
mtb:ResidentialRealEstateExcludingAltAMember
mtb:LongTermDebtTwoThousandSeventeenMember
us-gaap:FinancialAssetNotPastDueMember
2020-12-31
0000036270
mtb:ResidentialRealEstateExcludingAltAMember
mtb:LongTermDebtTwoThousandSixteenMember
us-gaap:FinancialAssetNotPastDueMember
2020-12-31
0000036270
mtb:ResidentialRealEstateExcludingAltAMember
mtb:LongTermDebtPriorPeriodMember
us-gaap:FinancialAssetNotPastDueMember
2020-12-31
0000036270
mtb:ResidentialRealEstateExcludingAltAMember
us-gaap:RevolvingCreditFacilityMember
us-gaap:FinancialAssetNotPastDueMember
2020-12-31
0000036270
mtb:ResidentialRealEstateExcludingAltAMember
mtb:LongTermDebtTwoThousandTwentyMember
2020-12-31
0000036270
mtb:ResidentialRealEstateExcludingAltAMember
mtb:LongTermDebtTwoThousandNineteenMember
2020-12-31
0000036270
mtb:ResidentialRealEstateExcludingAltAMember
mtb:LongTermDebtTwoThousandEighteenMember
2020-12-31
0000036270
mtb:ResidentialRealEstateExcludingAltAMember
mtb:LongTermDebtTwoThousandSeventeenMember
2020-12-31
0000036270
mtb:ResidentialRealEstateExcludingAltAMember
mtb:LongTermDebtTwoThousandSixteenMember
2020-12-31
0000036270
mtb:ResidentialRealEstateExcludingAltAMember
mtb:LongTermDebtPriorPeriodMember
2020-12-31
0000036270
mtb:ResidentialRealEstateExcludingAltAMember
us-gaap:RevolvingCreditFacilityMember
2020-12-31
0000036270
mtb:ResidentialLimitedDocumentationMember
mtb:LongTermDebtPriorPeriodMember
us-gaap:FinancialAssetNotPastDueMember
2020-12-31
0000036270
mtb:ResidentialLimitedDocumentationMember
mtb:LongTermDebtPriorPeriodMember
2020-12-31
0000036270
mtb:HomeEquityLinesAndLoansMember
mtb:LongTermDebtTwoThousandTwentyMember
us-gaap:FinancialAssetNotPastDueMember
2020-12-31
0000036270
mtb:HomeEquityLinesAndLoansMember
mtb:LongTermDebtTwoThousandNineteenMember
us-gaap:FinancialAssetNotPastDueMember
2020-12-31
0000036270
mtb:HomeEquityLinesAndLoansMember
mtb:LongTermDebtTwoThousandEighteenMember
us-gaap:FinancialAssetNotPastDueMember
2020-12-31
0000036270
mtb:HomeEquityLinesAndLoansMember
mtb:LongTermDebtTwoThousandSeventeenMember
us-gaap:FinancialAssetNotPastDueMember
2020-12-31
0000036270
mtb:HomeEquityLinesAndLoansMember
mtb:LongTermDebtTwoThousandSixteenMember
us-gaap:FinancialAssetNotPastDueMember
2020-12-31
0000036270
mtb:HomeEquityLinesAndLoansMember
mtb:LongTermDebtPriorPeriodMember
us-gaap:FinancialAssetNotPastDueMember
2020-12-31
0000036270
mtb:HomeEquityLinesAndLoansMember
us-gaap:RevolvingCreditFacilityMember
us-gaap:FinancialAssetNotPastDueMember
2020-12-31
0000036270
mtb:HomeEquityLinesAndLoansMember
mtb:RevolvingLoansConvertedToTermLoansMember
us-gaap:FinancialAssetNotPastDueMember
2020-12-31
0000036270
mtb:HomeEquityLinesAndLoansMember
mtb:LongTermDebtPriorPeriodMember
2020-12-31
0000036270
mtb:HomeEquityLinesAndLoansMember
us-gaap:RevolvingCreditFacilityMember
2020-12-31
0000036270
mtb:HomeEquityLinesAndLoansMember
mtb:RevolvingLoansConvertedToTermLoansMember
2020-12-31
0000036270
mtb:HomeEquityLinesAndLoansMember
mtb:LongTermDebtTwoThousandTwentyMember
2020-12-31
0000036270
mtb:HomeEquityLinesAndLoansMember
mtb:LongTermDebtTwoThousandNineteenMember
2020-12-31
0000036270
mtb:HomeEquityLinesAndLoansMember
mtb:LongTermDebtTwoThousandEighteenMember
2020-12-31
0000036270
mtb:HomeEquityLinesAndLoansMember
mtb:LongTermDebtTwoThousandSeventeenMember
2020-12-31
0000036270
mtb:HomeEquityLinesAndLoansMember
mtb:LongTermDebtTwoThousandSixteenMember
2020-12-31
0000036270
mtb:RecreationalFinanceMember
mtb:LongTermDebtTwoThousandTwentyMember
us-gaap:FinancialAssetNotPastDueMember
2020-12-31
0000036270
mtb:RecreationalFinanceMember
mtb:LongTermDebtTwoThousandNineteenMember
us-gaap:FinancialAssetNotPastDueMember
2020-12-31
0000036270
mtb:RecreationalFinanceMember
mtb:LongTermDebtTwoThousandEighteenMember
us-gaap:FinancialAssetNotPastDueMember
2020-12-31
0000036270
mtb:RecreationalFinanceMember
mtb:LongTermDebtTwoThousandSeventeenMember
us-gaap:FinancialAssetNotPastDueMember
2020-12-31
0000036270
mtb:RecreationalFinanceMember
mtb:LongTermDebtTwoThousandSixteenMember
us-gaap:FinancialAssetNotPastDueMember
2020-12-31
0000036270
mtb:RecreationalFinanceMember
mtb:LongTermDebtPriorPeriodMember
us-gaap:FinancialAssetNotPastDueMember
2020-12-31
0000036270
mtb:RecreationalFinanceMember
mtb:LongTermDebtTwoThousandTwentyMember
2020-12-31
0000036270
mtb:RecreationalFinanceMember
mtb:LongTermDebtTwoThousandNineteenMember
2020-12-31
0000036270
mtb:RecreationalFinanceMember
mtb:LongTermDebtTwoThousandEighteenMember
2020-12-31
0000036270
mtb:RecreationalFinanceMember
mtb:LongTermDebtTwoThousandSeventeenMember
2020-12-31
0000036270
mtb:RecreationalFinanceMember
mtb:LongTermDebtTwoThousandSixteenMember
2020-12-31
0000036270
mtb:RecreationalFinanceMember
mtb:LongTermDebtPriorPeriodMember
2020-12-31
0000036270
us-gaap:AutomobileLoanMember
mtb:LongTermDebtTwoThousandTwentyMember
us-gaap:FinancialAssetNotPastDueMember
2020-12-31
0000036270
us-gaap:AutomobileLoanMember
mtb:LongTermDebtTwoThousandNineteenMember
us-gaap:FinancialAssetNotPastDueMember
2020-12-31
0000036270
us-gaap:AutomobileLoanMember
mtb:LongTermDebtTwoThousandEighteenMember
us-gaap:FinancialAssetNotPastDueMember
2020-12-31
0000036270
us-gaap:AutomobileLoanMember
mtb:LongTermDebtTwoThousandSeventeenMember
us-gaap:FinancialAssetNotPastDueMember
2020-12-31
0000036270
us-gaap:AutomobileLoanMember
mtb:LongTermDebtTwoThousandSixteenMember
us-gaap:FinancialAssetNotPastDueMember
2020-12-31
0000036270
us-gaap:AutomobileLoanMember
mtb:LongTermDebtPriorPeriodMember
us-gaap:FinancialAssetNotPastDueMember
2020-12-31
0000036270
us-gaap:AutomobileLoanMember
mtb:LongTermDebtTwoThousandTwentyMember
2020-12-31
0000036270
us-gaap:AutomobileLoanMember
mtb:LongTermDebtTwoThousandNineteenMember
2020-12-31
0000036270
us-gaap:AutomobileLoanMember
mtb:LongTermDebtTwoThousandEighteenMember
2020-12-31
0000036270
us-gaap:AutomobileLoanMember
mtb:LongTermDebtTwoThousandSeventeenMember
2020-12-31
0000036270
us-gaap:AutomobileLoanMember
mtb:LongTermDebtTwoThousandSixteenMember
2020-12-31
0000036270
us-gaap:AutomobileLoanMember
mtb:LongTermDebtPriorPeriodMember
2020-12-31
0000036270
mtb:OtherLoansMember
mtb:LongTermDebtTwoThousandTwentyMember
us-gaap:FinancialAssetNotPastDueMember
2020-12-31
0000036270
mtb:OtherLoansMember
mtb:LongTermDebtTwoThousandNineteenMember
us-gaap:FinancialAssetNotPastDueMember
2020-12-31
0000036270
mtb:OtherLoansMember
mtb:LongTermDebtTwoThousandEighteenMember
us-gaap:FinancialAssetNotPastDueMember
2020-12-31
0000036270
mtb:OtherLoansMember
mtb:LongTermDebtTwoThousandSeventeenMember
us-gaap:FinancialAssetNotPastDueMember
2020-12-31
0000036270
mtb:OtherLoansMember
mtb:LongTermDebtTwoThousandSixteenMember
us-gaap:FinancialAssetNotPastDueMember
2020-12-31
0000036270
mtb:OtherLoansMember
mtb:LongTermDebtPriorPeriodMember
us-gaap:FinancialAssetNotPastDueMember
2020-12-31
0000036270
us-gaap:RevolvingCreditFacilityMember
mtb:OtherLoansMember
us-gaap:FinancialAssetNotPastDueMember
2020-12-31
0000036270
mtb:RevolvingLoansConvertedToTermLoansMember
mtb:OtherLoansMember
us-gaap:FinancialAssetNotPastDueMember
2020-12-31
0000036270
mtb:OtherLoansMember
mtb:LongTermDebtTwoThousandTwentyMember
2020-12-31
0000036270
mtb:OtherLoansMember
mtb:LongTermDebtTwoThousandNineteenMember
2020-12-31
0000036270
mtb:OtherLoansMember
mtb:LongTermDebtTwoThousandEighteenMember
2020-12-31
0000036270
mtb:OtherLoansMember
mtb:LongTermDebtTwoThousandSeventeenMember
2020-12-31
0000036270
mtb:OtherLoansMember
mtb:LongTermDebtTwoThousandSixteenMember
2020-12-31
0000036270
mtb:OtherLoansMember
mtb:LongTermDebtPriorPeriodMember
2020-12-31
0000036270
us-gaap:RevolvingCreditFacilityMember
mtb:OtherLoansMember
2020-12-31
0000036270
mtb:RevolvingLoansConvertedToTermLoansMember
mtb:OtherLoansMember
2020-12-31
0000036270
mtb:LongTermDebtTwoThousandTwentyMember
2020-12-31
0000036270
mtb:LongTermDebtTwoThousandNineteenMember
2020-12-31
0000036270
mtb:LongTermDebtTwoThousandEighteenMember
2020-12-31
0000036270
mtb:LongTermDebtTwoThousandSeventeenMember
2020-12-31
0000036270
mtb:LongTermDebtTwoThousandSixteenMember
2020-12-31
0000036270
mtb:LongTermDebtPriorPeriodMember
2020-12-31
0000036270
us-gaap:RevolvingCreditFacilityMember
2020-12-31
0000036270
mtb:RevolvingLoansConvertedToTermLoansMember
2020-12-31
0000036270
mtb:OwnedAssetsMember
2021-12-31
0000036270
mtb:OwnedAssetsMember
2020-12-31
0000036270
us-gaap:AssetsHeldUnderCapitalLeasesMember
2021-12-31
0000036270
us-gaap:AssetsHeldUnderCapitalLeasesMember
2020-12-31
0000036270
us-gaap:ResidentialMortgageMember
2020-12-31
0000036270
us-gaap:ResidentialMortgageMember
2019-12-31
0000036270
us-gaap:ResidentialMortgageMember
2018-12-31
0000036270
us-gaap:CommercialLoanMember
2020-12-31
0000036270
us-gaap:CommercialLoanMember
2019-12-31
0000036270
us-gaap:CommercialLoanMember
2018-12-31
0000036270
us-gaap:ResidentialMortgageMember
2021-01-01
2021-12-31
0000036270
us-gaap:ResidentialMortgageMember
2020-01-01
2020-12-31
0000036270
us-gaap:ResidentialMortgageMember
2019-01-01
2019-12-31
0000036270
us-gaap:CommercialLoanMember
2021-01-01
2021-12-31
0000036270
us-gaap:CommercialLoanMember
2020-01-01
2020-12-31
0000036270
us-gaap:CommercialLoanMember
2019-01-01
2019-12-31
0000036270
us-gaap:CommercialLoanMember
2021-12-31
0000036270
mtb:SubServicingLoanMember
2021-12-31
0000036270
mtb:SubServicingLoanMember
2020-12-31
0000036270
mtb:SubServicingLoanMember
2019-12-31
0000036270
us-gaap:ResidentialRealEstateMember
2019-01-31
0000036270
us-gaap:ResidentialRealEstateMember
2019-01-01
2019-01-31
0000036270
mtb:SubServicingLoanOneMember
2021-12-31
0000036270
mtb:SubServicingLoanOneMember
2020-12-31
0000036270
mtb:SubServicingLoanOneMember
2019-12-31
0000036270
us-gaap:ResidentialMortgageMember
2021-12-30
2021-12-31
0000036270
us-gaap:ResidentialMortgageMember
2020-12-30
2020-12-31
0000036270
us-gaap:ResidentialMortgageMember
us-gaap:LondonInterbankOfferedRateLIBORMember
2021-01-01
2021-12-31
0000036270
us-gaap:ResidentialMortgageMember
us-gaap:LondonInterbankOfferedRateLIBORMember
2020-01-01
2020-12-31
0000036270
us-gaap:CommercialLoanMember
2021-12-30
2021-12-31
0000036270
us-gaap:CommercialLoanMember
2020-12-30
2020-12-31
0000036270
us-gaap:CoreDepositsMember
2021-12-31
0000036270
us-gaap:OtherIntangibleAssetsMember
2021-12-31
0000036270
us-gaap:CoreDepositsMember
2020-12-31
0000036270
us-gaap:OtherIntangibleAssetsMember
2020-12-31
0000036270
mtb:CoreDepositsAndOtherIntangibleAssetsMember
srt:MinimumMember
2021-01-01
2021-12-31
0000036270
mtb:CoreDepositsAndOtherIntangibleAssetsMember
srt:MaximumMember
2021-01-01
2021-12-31
0000036270
mtb:CoreDepositsAndOtherIntangibleAssetsMember
2021-01-01
2021-12-31
0000036270
mtb:CoreDepositsAndOtherIntangibleAssetsMember
2020-01-01
2020-12-31
0000036270
mtb:CoreDepositsAndOtherIntangibleAssetsMember
2019-01-01
2019-12-31
0000036270
mtb:CoreDepositsAndOtherIntangibleAssetsMember
2021-12-31
0000036270
mtb:BusinessBankingMember
2021-12-31
0000036270
mtb:CommercialBankingMember
2021-12-31
0000036270
mtb:CommercialRealEstateSegmentMember
2021-12-31
0000036270
mtb:RetailBankingMember
2021-12-31
0000036270
us-gaap:AllOtherSegmentsMember
2021-12-31
0000036270
us-gaap:FederalFundsPurchasedMember
2021-12-31
0000036270
us-gaap:FederalFundsPurchasedMember
2021-01-01
2021-12-31
0000036270
us-gaap:FederalFundsPurchasedMember
2020-12-31
0000036270
us-gaap:FederalFundsPurchasedMember
2020-01-01
2020-12-31
0000036270
us-gaap:FederalFundsPurchasedMember
2019-12-31
0000036270
us-gaap:FederalFundsPurchasedMember
2019-01-01
2019-12-31
0000036270
mtb:OtherShortTermBorrowingsMember
2019-01-01
2019-12-31
0000036270
us-gaap:ShortTermDebtMember
2021-01-01
2021-12-31
0000036270
mtb:MAndTBankMember
2021-12-31
0000036270
us-gaap:FederalHomeLoanBankAdvancesMember
2021-12-31
0000036270
mtb:FederalReserveBankOfNewYorkMember
2021-12-31
0000036270
mtb:VariableRateTermLoansDueTwoThousandAndTwentyThreeMember
mtb:MAndTMember
2021-12-31
0000036270
mtb:VariableRateTermLoansDueTwoThousandAndTwentyThreeMember
mtb:MAndTMember
2020-12-31
0000036270
mtb:FixedRateThreePointFiveFivePercentageDueTwoThousandTwentyThreeMember
mtb:MAndTMember
2021-12-31
0000036270
mtb:FixedRateThreePointFiveFivePercentageDueTwoThousandTwentyThreeMember
mtb:MAndTMember
2020-12-31
0000036270
mtb:VariableRateTermLoansDueTwoThousandTwentyOneMember
2020-12-31
0000036270
mtb:VariableRateTermLoansDueTwoThousandAndTwentyTwoMember
2021-12-31
0000036270
mtb:VariableRateTermLoansDueTwoThousandAndTwentyTwoMember
2020-12-31
0000036270
mtb:FixedRateTermLoansOfTwoPointFiveZeroSeniorNotesDueTwoThousandTwentyTwoMember
2021-12-31
0000036270
mtb:FixedRateTermLoansOfTwoPointFiveZeroSeniorNotesDueTwoThousandTwentyTwoMember
2020-12-31
0000036270
mtb:FixedRateTermLoansOfSeniorNotesDueTwoThousandTwentyFiveMember
2021-12-31
0000036270
mtb:FixedRateTermLoansOfSeniorNotesDueTwoThousandTwentyFiveMember
2020-12-31
0000036270
mtb:VariableRateSubordinatedNotesDueTwoThousandAndTwentyOneMember
2020-12-31
0000036270
mtb:SubordinatedNotesDueTwoZeroTwoSevenMember
2021-12-31
0000036270
mtb:SubordinatedNotesDueTwoZeroTwoSevenMember
2020-12-31
0000036270
mtb:BsbCapitalTrustOneFixedRatesDueTwoZeroTwoEightMember
2021-12-31
0000036270
mtb:BsbCapitalTrustOneFixedRatesDueTwoZeroTwoEightMember
2020-12-31
0000036270
mtb:ProvidentTrustOneFixedRatesDueTwoZeroTwoEightMember
2021-12-31
0000036270
mtb:ProvidentTrustOneFixedRatesDueTwoZeroTwoEightMember
2020-12-31
0000036270
mtb:SouthernFinancialStatutoryTrustOneFixedRatesDueTwoZeroThreeZeroMember
2021-12-31
0000036270
mtb:SouthernFinancialStatutoryTrustOneFixedRatesDueTwoZeroThreeZeroMember
2020-12-31
0000036270
mtb:FirstMarylandCapitalOneVariableRatesDueTwoZeroTwoSevenMember
2021-12-31
0000036270
mtb:FirstMarylandCapitalOneVariableRatesDueTwoZeroTwoSevenMember
2020-12-31
0000036270
mtb:FirstMarylandCapitalTwoVariableRatesDueTwoZeroTwoSevenMember
2021-12-31
0000036270
mtb:FirstMarylandCapitalTwoVariableRatesDueTwoZeroTwoSevenMember
2020-12-31
0000036270
mtb:AllfirstAssetTrustVariableRatesDueTwoZeroTwoNineMember
2021-12-31
0000036270
mtb:AllfirstAssetTrustVariableRatesDueTwoZeroTwoNineMember
2020-12-31
0000036270
mtb:BsbCapitalTrustThreeVariableRateDueTwoZeroThreeThreeMember
2021-12-31
0000036270
mtb:BsbCapitalTrustThreeVariableRateDueTwoZeroThreeThreeMember
2020-12-31
0000036270
mtb:ProvidentTrustThreeStatutoryRateDueTwoZeroThreeThreeMember
2021-12-31
0000036270
mtb:ProvidentTrustThreeStatutoryRateDueTwoZeroThreeThreeMember
2020-12-31
0000036270
mtb:SouthernFinancialCapitalTrustThreeVariableRateDueTwoZeroThreeThreeMember
2021-12-31
0000036270
mtb:SouthernFinancialCapitalTrustThreeVariableRateDueTwoZeroThreeThreeMember
2020-12-31
0000036270
mtb:VariableRateTermLoansDueTwoThousandAndTwentyThreeMember
mtb:MAndTMember
2021-01-01
2021-12-31
0000036270
mtb:VariableRateTermLoansDueTwoThousandAndTwentyThreeMember
mtb:MAndTMember
2020-01-01
2020-12-31
0000036270
mtb:FixedRateThreePointFiveFivePercentageDueTwoThousandTwentyThreeMember
mtb:MAndTMember
2021-01-01
2021-12-31
0000036270
mtb:FixedRateThreePointFiveFivePercentageDueTwoThousandTwentyThreeMember
mtb:MAndTMember
2020-01-01
2020-12-31
0000036270
mtb:VariableRateTermLoansDueTwoThousandTwentyOneMember
2021-01-01
2021-12-31
0000036270
mtb:VariableRateTermLoansDueTwoThousandTwentyOneMember
2020-01-01
2020-12-31
0000036270
mtb:VariableRateTermLoansDueTwoThousandAndTwentyTwoMember
2021-01-01
2021-12-31
0000036270
mtb:VariableRateTermLoansDueTwoThousandAndTwentyTwoMember
2020-01-01
2020-12-31
0000036270
mtb:FixedRateTermLoansOfTwoPointFiveZeroSeniorNotesDueTwoThousandTwentyTwoMember
2021-01-01
2021-12-31
0000036270
mtb:FixedRateTermLoansOfTwoPointFiveZeroSeniorNotesDueTwoThousandTwentyTwoMember
2020-01-01
2020-12-31
0000036270
mtb:FixedRateTermLoansOfSeniorNotesDueTwoThousandTwentyFiveMember
2021-01-01
2021-12-31
0000036270
mtb:FixedRateTermLoansOfSeniorNotesDueTwoThousandTwentyFiveMember
2020-01-01
2020-12-31
0000036270
mtb:VariableRateSubordinatedNotesDueTwoThousandAndTwentyOneMember
2021-01-01
2021-12-31
0000036270
mtb:VariableRateSubordinatedNotesDueTwoThousandAndTwentyOneMember
2020-01-01
2020-12-31
0000036270
mtb:SubordinatedNotesDueTwoZeroTwoSevenMember
2021-01-01
2021-12-31
0000036270
mtb:SubordinatedNotesDueTwoZeroTwoSevenMember
2020-01-01
2020-12-31
0000036270
mtb:BsbCapitalTrustOneFixedRatesDueTwoZeroTwoEightMember
2021-01-01
2021-12-31
0000036270
mtb:BsbCapitalTrustOneFixedRatesDueTwoZeroTwoEightMember
2020-01-01
2020-12-31
0000036270
mtb:ProvidentTrustOneFixedRatesDueTwoZeroTwoEightMember
2021-01-01
2021-12-31
0000036270
mtb:ProvidentTrustOneFixedRatesDueTwoZeroTwoEightMember
2020-01-01
2020-12-31
0000036270
mtb:SouthernFinancialStatutoryTrustOneFixedRatesDueTwoZeroThreeZeroMember
2021-01-01
2021-12-31
0000036270
mtb:SouthernFinancialStatutoryTrustOneFixedRatesDueTwoZeroThreeZeroMember
2020-01-01
2020-12-31
0000036270
mtb:FirstMarylandCapitalOneVariableRatesDueTwoZeroTwoSevenMember
2021-01-01
2021-12-31
0000036270
mtb:FirstMarylandCapitalOneVariableRatesDueTwoZeroTwoSevenMember
2020-01-01
2020-12-31
0000036270
mtb:FirstMarylandCapitalTwoVariableRatesDueTwoZeroTwoSevenMember
2021-01-01
2021-12-31
0000036270
mtb:FirstMarylandCapitalTwoVariableRatesDueTwoZeroTwoSevenMember
2020-01-01
2020-12-31
0000036270
mtb:AllfirstAssetTrustVariableRatesDueTwoZeroTwoNineMember
2021-01-01
2021-12-31
0000036270
mtb:AllfirstAssetTrustVariableRatesDueTwoZeroTwoNineMember
2020-01-01
2020-12-31
0000036270
mtb:BsbCapitalTrustThreeVariableRateDueTwoZeroThreeThreeMember
2021-01-01
2021-12-31
0000036270
mtb:BsbCapitalTrustThreeVariableRateDueTwoZeroThreeThreeMember
2020-01-01
2020-12-31
0000036270
mtb:ProvidentTrustThreeStatutoryRateDueTwoZeroThreeThreeMember
2021-01-01
2021-12-31
0000036270
mtb:ProvidentTrustThreeStatutoryRateDueTwoZeroThreeThreeMember
2020-01-01
2020-12-31
0000036270
mtb:SouthernFinancialCapitalTrustThreeVariableRateDueTwoZeroThreeThreeMember
2021-01-01
2021-12-31
0000036270
mtb:SouthernFinancialCapitalTrustThreeVariableRateDueTwoZeroThreeThreeMember
2020-01-01
2020-12-31
0000036270
mtb:SeniorNotesIssuedJulyTwoThousandAndEighteenMember
2020-12-31
0000036270
mtb:SeniorNotesIssuedJulyTwoThousandAndEighteenMember
2021-12-31
0000036270
mtb:FloatingRateSeniorNotesMember
srt:MinimumMember
2021-12-31
0000036270
mtb:FloatingRateSeniorNotesMember
srt:MaximumMember
2021-12-31
0000036270
mtb:FloatingRateSeniorNotesMember
srt:MinimumMember
2020-12-31
0000036270
mtb:FloatingRateSeniorNotesMember
srt:MaximumMember
2020-12-31
0000036270
mtb:FloatingRateSeniorNotesMember
2020-12-31
0000036270
mtb:FloatingRateSeniorNotesMember
2021-12-31
0000036270
mtb:LongTermFixedRateAdvancesFromFhlbMember
srt:WeightedAverageMember
2021-12-31
0000036270
mtb:LongTermFixedRateAdvancesFromFhlbMember
srt:WeightedAverageMember
2020-12-31
0000036270
mtb:LongTermFixedRateAdvancesFromFhlbMember
2021-12-31
0000036270
us-gaap:SubordinatedDebtMember
2020-12-31
0000036270
srt:MinimumMember
2021-12-31
0000036270
srt:MinimumMember
2020-12-31
0000036270
srt:MaximumMember
2021-12-31
0000036270
srt:MaximumMember
2020-12-31
0000036270
us-gaap:JuniorSubordinatedDebtMember
2021-12-31
0000036270
us-gaap:JuniorSubordinatedDebtMember
2020-12-31
0000036270
mtb:SeriesEFixedToFloatingRateNonCumulativePerpetualPreferredStockMember
2021-12-31
0000036270
mtb:SeriesFFixedToFloatingRateNonCumulativePerpetualPreferredStockMember
2021-12-31
0000036270
mtb:SeriesGFixedRateResetNonCumulativePerpetualPreferredStockMember
2021-12-31
0000036270
mtb:SeriesIFixedRateResetNonCumulativePerpetualPreferredStockMember
2021-12-31
0000036270
mtb:SeriesEFixedToFloatingRateNonCumulativePerpetualPreferredStockMember
2020-12-31
0000036270
mtb:SeriesFFixedToFloatingRateNonCumulativePerpetualPreferredStockMember
2020-12-31
0000036270
mtb:SeriesGFixedRateResetNonCumulativePerpetualPreferredStockMember
2020-12-31
0000036270
mtb:SeriesEFixedToFloatingRateNonCumulativePerpetualPreferredStockMember
2021-01-01
2021-12-31
0000036270
mtb:SeriesEFixedToFloatingRateNonCumulativePerpetualPreferredStockMember
2020-01-01
2020-12-31
0000036270
mtb:SeriesEFixedToFloatingRateNonCumulativePerpetualPreferredStockMember
2019-01-01
2019-12-31
0000036270
mtb:SeriesFFixedToFloatingRateNonCumulativePerpetualPreferredStockMember
2021-01-01
2021-12-31
0000036270
mtb:SeriesFFixedToFloatingRateNonCumulativePerpetualPreferredStockMember
2020-01-01
2020-12-31
0000036270
mtb:SeriesFFixedToFloatingRateNonCumulativePerpetualPreferredStockMember
2019-01-01
2019-12-31
0000036270
mtb:SeriesGFixedRateResetNonCumulativePerpetualPreferredStockMember
2021-01-01
2021-12-31
0000036270
mtb:SeriesGFixedRateResetNonCumulativePerpetualPreferredStockMember
2020-01-01
2020-12-31
0000036270
mtb:SeriesGFixedRateResetNonCumulativePerpetualPreferredStockMember
2019-01-01
2019-12-31
0000036270
mtb:SeriesIFixedRateResetNonCumulativePerpetualPreferredStockMember
2021-01-01
2021-12-31
0000036270
mtb:SeriesIFixedRateResetNonCumulativePerpetualPreferredStockMember
2020-01-01
2020-12-31
0000036270
srt:MaximumMember
2022-01-01
2021-12-31
0000036270
us-gaap:OtherLiabilitiesMember
2021-12-31
0000036270
us-gaap:OtherLiabilitiesMember
2020-12-31
0000036270
mtb:BusinessBankingMember
us-gaap:DepositAccountMember
us-gaap:AccountingStandardsUpdate201409Member
2021-01-01
2021-12-31
0000036270
mtb:CommercialBankingMember
us-gaap:DepositAccountMember
us-gaap:AccountingStandardsUpdate201409Member
2021-01-01
2021-12-31
0000036270
mtb:CommercialRealEstateSegmentMember
us-gaap:DepositAccountMember
us-gaap:AccountingStandardsUpdate201409Member
2021-01-01
2021-12-31
0000036270
mtb:RetailBankingMember
us-gaap:DepositAccountMember
us-gaap:AccountingStandardsUpdate201409Member
2021-01-01
2021-12-31
0000036270
us-gaap:AllOtherSegmentsMember
us-gaap:DepositAccountMember
us-gaap:AccountingStandardsUpdate201409Member
2021-01-01
2021-12-31
0000036270
us-gaap:DepositAccountMember
us-gaap:AccountingStandardsUpdate201409Member
2021-01-01
2021-12-31
0000036270
us-gaap:AllOtherSegmentsMember
us-gaap:FiduciaryAndTrustMember
us-gaap:AccountingStandardsUpdate201409Member
2021-01-01
2021-12-31
0000036270
us-gaap:FiduciaryAndTrustMember
us-gaap:AccountingStandardsUpdate201409Member
2021-01-01
2021-12-31
0000036270
us-gaap:AllOtherSegmentsMember
us-gaap:AccountingStandardsUpdate201409Member
2021-01-01
2021-12-31
0000036270
mtb:BusinessBankingMember
us-gaap:AccountingStandardsUpdate201409Member
2021-01-01
2021-12-31
0000036270
mtb:CommercialBankingMember
us-gaap:AccountingStandardsUpdate201409Member
2021-01-01
2021-12-31
0000036270
mtb:CommercialRealEstateSegmentMember
us-gaap:AccountingStandardsUpdate201409Member
2021-01-01
2021-12-31
0000036270
mtb:RetailBankingMember
us-gaap:AccountingStandardsUpdate201409Member
2021-01-01
2021-12-31
0000036270
mtb:DiscretionaryPortfolioMember
us-gaap:AccountingStandardsUpdate201409Member
2021-01-01
2021-12-31
0000036270
mtb:ResidentialMortgageBankingMember
us-gaap:AccountingStandardsUpdate201409Member
2021-01-01
2021-12-31
0000036270
mtb:BusinessBankingMember
us-gaap:DepositAccountMember
us-gaap:AccountingStandardsUpdate201409Member
2020-01-01
2020-12-31
0000036270
mtb:CommercialBankingMember
us-gaap:DepositAccountMember
us-gaap:AccountingStandardsUpdate201409Member
2020-01-01
2020-12-31
0000036270
mtb:CommercialRealEstateSegmentMember
us-gaap:DepositAccountMember
us-gaap:AccountingStandardsUpdate201409Member
2020-01-01
2020-12-31
0000036270
mtb:RetailBankingMember
us-gaap:DepositAccountMember
us-gaap:AccountingStandardsUpdate201409Member
2020-01-01
2020-12-31
0000036270
us-gaap:AllOtherSegmentsMember
us-gaap:DepositAccountMember
us-gaap:AccountingStandardsUpdate201409Member
2020-01-01
2020-12-31
0000036270
us-gaap:DepositAccountMember
us-gaap:AccountingStandardsUpdate201409Member
2020-01-01
2020-12-31
0000036270
mtb:BusinessBankingMember
us-gaap:FiduciaryAndTrustMember
us-gaap:AccountingStandardsUpdate201409Member
2020-01-01
2020-12-31
0000036270
mtb:CommercialBankingMember
us-gaap:FiduciaryAndTrustMember
us-gaap:AccountingStandardsUpdate201409Member
2020-01-01
2020-12-31
0000036270
us-gaap:AllOtherSegmentsMember
us-gaap:FiduciaryAndTrustMember
us-gaap:AccountingStandardsUpdate201409Member
2020-01-01
2020-12-31
0000036270
us-gaap:FiduciaryAndTrustMember
us-gaap:AccountingStandardsUpdate201409Member
2020-01-01
2020-12-31
0000036270
us-gaap:AllOtherSegmentsMember
us-gaap:AccountingStandardsUpdate201409Member
2020-01-01
2020-12-31
0000036270
us-gaap:AccountingStandardsUpdate201409Member
2020-01-01
2020-12-31
0000036270
mtb:BusinessBankingMember
us-gaap:AccountingStandardsUpdate201409Member
2020-01-01
2020-12-31
0000036270
mtb:CommercialBankingMember
us-gaap:AccountingStandardsUpdate201409Member
2020-01-01
2020-12-31
0000036270
mtb:CommercialRealEstateSegmentMember
us-gaap:AccountingStandardsUpdate201409Member
2020-01-01
2020-12-31
0000036270
mtb:RetailBankingMember
us-gaap:AccountingStandardsUpdate201409Member
2020-01-01
2020-12-31
0000036270
mtb:DiscretionaryPortfolioMember
us-gaap:AccountingStandardsUpdate201409Member
2020-01-01
2020-12-31
0000036270
mtb:ResidentialMortgageBankingMember
us-gaap:AccountingStandardsUpdate201409Member
2020-01-01
2020-12-31
0000036270
mtb:BusinessBankingMember
us-gaap:DepositAccountMember
us-gaap:AccountingStandardsUpdate201409Member
2019-01-01
2019-12-31
0000036270
mtb:CommercialBankingMember
us-gaap:DepositAccountMember
us-gaap:AccountingStandardsUpdate201409Member
2019-01-01
2019-12-31
0000036270
mtb:CommercialRealEstateSegmentMember
us-gaap:DepositAccountMember
us-gaap:AccountingStandardsUpdate201409Member
2019-01-01
2019-12-31
0000036270
mtb:ResidentialMortgageBankingMember
us-gaap:DepositAccountMember
us-gaap:AccountingStandardsUpdate201409Member
2019-01-01
2019-12-31
0000036270
mtb:RetailBankingMember
us-gaap:DepositAccountMember
us-gaap:AccountingStandardsUpdate201409Member
2019-01-01
2019-12-31
0000036270
us-gaap:AllOtherSegmentsMember
us-gaap:DepositAccountMember
us-gaap:AccountingStandardsUpdate201409Member
2019-01-01
2019-12-31
0000036270
us-gaap:DepositAccountMember
us-gaap:AccountingStandardsUpdate201409Member
2019-01-01
2019-12-31
0000036270
mtb:BusinessBankingMember
us-gaap:FiduciaryAndTrustMember
us-gaap:AccountingStandardsUpdate201409Member
2019-01-01
2019-12-31
0000036270
mtb:CommercialBankingMember
us-gaap:FiduciaryAndTrustMember
us-gaap:AccountingStandardsUpdate201409Member
2019-01-01
2019-12-31
0000036270
us-gaap:AllOtherSegmentsMember
us-gaap:FiduciaryAndTrustMember
us-gaap:AccountingStandardsUpdate201409Member
2019-01-01
2019-12-31
0000036270
us-gaap:FiduciaryAndTrustMember
us-gaap:AccountingStandardsUpdate201409Member
2019-01-01
2019-12-31
0000036270
us-gaap:AllOtherSegmentsMember
us-gaap:AccountingStandardsUpdate201409Member
2019-01-01
2019-12-31
0000036270
us-gaap:AccountingStandardsUpdate201409Member
2019-01-01
2019-12-31
0000036270
mtb:BusinessBankingMember
us-gaap:AccountingStandardsUpdate201409Member
2019-01-01
2019-12-31
0000036270
mtb:CommercialBankingMember
us-gaap:AccountingStandardsUpdate201409Member
2019-01-01
2019-12-31
0000036270
mtb:CommercialRealEstateSegmentMember
us-gaap:AccountingStandardsUpdate201409Member
2019-01-01
2019-12-31
0000036270
mtb:RetailBankingMember
us-gaap:AccountingStandardsUpdate201409Member
2019-01-01
2019-12-31
0000036270
mtb:DiscretionaryPortfolioMember
us-gaap:AccountingStandardsUpdate201409Member
2019-01-01
2019-12-31
0000036270
mtb:ResidentialMortgageBankingMember
us-gaap:AccountingStandardsUpdate201409Member
2019-01-01
2019-12-31
0000036270
us-gaap:RestrictedStockMember
2021-01-01
2021-12-31
0000036270
us-gaap:RestrictedStockMember
2020-01-01
2020-12-31
0000036270
us-gaap:RestrictedStockMember
2019-01-01
2019-12-31
0000036270
us-gaap:RestrictedStockUnitsRSUMember
2021-12-31
0000036270
us-gaap:RestrictedStockUnitsRSUMember
2021-01-01
2021-12-31
0000036270
us-gaap:RestrictedStockUnitsRSUMember
2020-01-01
2020-12-31
0000036270
us-gaap:RestrictedStockUnitsRSUMember
2019-01-01
2019-12-31
0000036270
us-gaap:RestrictedStockUnitsRSUMember
2020-12-31
0000036270
us-gaap:RestrictedStockMember
2020-12-31
0000036270
us-gaap:RestrictedStockMember
2021-12-31
0000036270
us-gaap:EmployeeStockOptionMember
2021-01-01
2021-12-31
0000036270
us-gaap:EmployeeStockOptionMember
2020-01-01
2020-12-31
0000036270
us-gaap:EmployeeStockOptionMember
2019-01-01
2019-12-31
0000036270
mtb:EmployeeStockPurchasePlanMember
2021-12-31
0000036270
mtb:EmployeeStockPurchasePlanMember
2021-01-01
2021-12-31
0000036270
mtb:EmployeeStockPurchasePlanMember
2020-01-01
2020-12-31
0000036270
mtb:EmployeeStockPurchasePlanMember
2019-01-01
2019-12-31
0000036270
mtb:EmployeeMember
2021-12-31
0000036270
mtb:EmployeeMember
2020-12-31
0000036270
srt:DirectorMember
2021-01-01
2021-12-31
0000036270
srt:DirectorMember
2021-12-31
0000036270
srt:DirectorMember
2020-12-31
0000036270
us-gaap:PensionPlansDefinedBenefitMember
2021-01-01
2021-12-31
0000036270
us-gaap:PensionPlansDefinedBenefitMember
2020-01-01
2020-12-31
0000036270
us-gaap:PensionPlansDefinedBenefitMember
2019-01-01
2019-12-31
0000036270
us-gaap:OtherPostretirementBenefitPlansDefinedBenefitMember
2021-01-01
2021-12-31
0000036270
us-gaap:OtherPostretirementBenefitPlansDefinedBenefitMember
2020-01-01
2020-12-31
0000036270
us-gaap:OtherPostretirementBenefitPlansDefinedBenefitMember
2019-01-01
2019-12-31
0000036270
us-gaap:PensionPlansDefinedBenefitMember
2020-12-31
0000036270
us-gaap:OtherPostretirementBenefitPlansDefinedBenefitMember
2020-12-31
0000036270
us-gaap:PensionPlansDefinedBenefitMember
2021-12-31
0000036270
us-gaap:OtherPostretirementBenefitPlansDefinedBenefitMember
2021-12-31
0000036270
us-gaap:PensionPlansDefinedBenefitMember
2019-12-31
0000036270
us-gaap:OtherPostretirementBenefitPlansDefinedBenefitMember
2019-12-31
0000036270
mtb:SupplementalPensionPlanMember
2021-12-31
0000036270
mtb:SupplementalPensionPlanMember
2020-12-31
0000036270
us-gaap:EquitySecuritiesMember
srt:MinimumMember
2021-12-31
0000036270
mtb:DebtSecurityMember
srt:MinimumMember
2021-12-31
0000036270
mtb:OtherSecuritiesMember
srt:MinimumMember
2021-12-31
0000036270
us-gaap:EquitySecuritiesMember
srt:MaximumMember
2021-12-31
0000036270
mtb:DebtSecurityMember
srt:MaximumMember
2021-12-31
0000036270
mtb:OtherSecuritiesMember
srt:MaximumMember
2021-12-31
0000036270
mtb:MoneyMarketInvestmentsMember
2021-12-31
0000036270
mtb:MAndTEquitySecuritiesMember
2021-12-31
0000036270
us-gaap:DefinedBenefitPlanEquitySecuritiesUsMember
2021-12-31
0000036270
us-gaap:DefinedBenefitPlanEquitySecuritiesNonUsMember
2021-12-31
0000036270
mtb:DomesticMutualFundEquitySecuritiesMember
2021-12-31
0000036270
mtb:InternationalMutualFundEquitySecuritiesMember
2021-12-31
0000036270
us-gaap:DefinedBenefitPlanEquitySecuritiesMember
2021-12-31
0000036270
us-gaap:CorporateDebtSecuritiesMember
2021-12-31
0000036270
us-gaap:USGovernmentAgenciesDebtSecuritiesMember
2021-12-31
0000036270
us-gaap:ForeignGovernmentDebtSecuritiesMember
2021-12-31
0000036270
mtb:DomesticMutualFundDebtSecuritiesMember
2021-12-31
0000036270
us-gaap:DefinedBenefitPlanDebtSecurityMember
2021-12-31
0000036270
mtb:OtherDiversifiedMutualFundMember
2021-12-31
0000036270
us-gaap:DefinedBenefitPlanRealEstateMember
2021-12-31
0000036270
us-gaap:PrivateEquityFundsMember
2021-12-31
0000036270
us-gaap:HedgeFundsMember
2021-12-31
0000036270
mtb:GuaranteedDepositFundMember
2021-12-31
0000036270
mtb:OtherSecuritiesMember
2021-12-31
0000036270
us-gaap:FairValueInputsLevel1Member
mtb:MoneyMarketInvestmentsMember
2021-12-31
0000036270
us-gaap:FairValueInputsLevel1Member
mtb:MAndTEquitySecuritiesMember
2021-12-31
0000036270
us-gaap:FairValueInputsLevel1Member
us-gaap:DefinedBenefitPlanEquitySecuritiesUsMember
2021-12-31
0000036270
us-gaap:FairValueInputsLevel1Member
us-gaap:DefinedBenefitPlanEquitySecuritiesNonUsMember
2021-12-31
0000036270
us-gaap:FairValueInputsLevel1Member
mtb:DomesticMutualFundEquitySecuritiesMember
2021-12-31
0000036270
us-gaap:FairValueInputsLevel1Member
mtb:InternationalMutualFundEquitySecuritiesMember
2021-12-31
0000036270
us-gaap:FairValueInputsLevel1Member
us-gaap:DefinedBenefitPlanEquitySecuritiesMember
2021-12-31
0000036270
us-gaap:FairValueInputsLevel1Member
mtb:DomesticMutualFundDebtSecuritiesMember
2021-12-31
0000036270
us-gaap:FairValueInputsLevel1Member
us-gaap:DefinedBenefitPlanDebtSecurityMember
2021-12-31
0000036270
us-gaap:FairValueInputsLevel1Member
mtb:OtherDiversifiedMutualFundMember
2021-12-31
0000036270
us-gaap:FairValueInputsLevel1Member
us-gaap:DefinedBenefitPlanRealEstateMember
2021-12-31
0000036270
us-gaap:FairValueInputsLevel1Member
us-gaap:HedgeFundsMember
2021-12-31
0000036270
us-gaap:FairValueInputsLevel1Member
mtb:OtherSecuritiesMember
2021-12-31
0000036270
us-gaap:FairValueInputsLevel1Member
2021-12-31
0000036270
us-gaap:FairValueInputsLevel2Member
mtb:MoneyMarketInvestmentsMember
2021-12-31
0000036270
us-gaap:FairValueInputsLevel2Member
us-gaap:CorporateDebtSecuritiesMember
2021-12-31
0000036270
us-gaap:FairValueInputsLevel2Member
us-gaap:USGovernmentAgenciesDebtSecuritiesMember
2021-12-31
0000036270
us-gaap:FairValueInputsLevel2Member
us-gaap:ForeignGovernmentDebtSecuritiesMember
2021-12-31
0000036270
us-gaap:FairValueInputsLevel2Member
us-gaap:DefinedBenefitPlanDebtSecurityMember
2021-12-31
0000036270
us-gaap:FairValueInputsLevel2Member
2021-12-31
0000036270
us-gaap:FairValueInputsLevel3Member
us-gaap:DefinedBenefitPlanRealEstateMember
2021-12-31
0000036270
us-gaap:FairValueInputsLevel3Member
us-gaap:PrivateEquityFundsMember
2021-12-31
0000036270
us-gaap:FairValueInputsLevel3Member
us-gaap:HedgeFundsMember
2021-12-31
0000036270
us-gaap:FairValueInputsLevel3Member
mtb:GuaranteedDepositFundMember
2021-12-31
0000036270
us-gaap:FairValueInputsLevel3Member
mtb:OtherSecuritiesMember
2021-12-31
0000036270
us-gaap:FairValueInputsLevel3Member
2021-12-31
0000036270
mtb:MoneyMarketInvestmentsMember
2020-12-31
0000036270
mtb:MAndTEquitySecuritiesMember
2020-12-31
0000036270
us-gaap:DefinedBenefitPlanEquitySecuritiesUsMember
2020-12-31
0000036270
us-gaap:DefinedBenefitPlanEquitySecuritiesNonUsMember
2020-12-31
0000036270
mtb:DomesticMutualFundEquitySecuritiesMember
2020-12-31
0000036270
mtb:InternationalMutualFundEquitySecuritiesMember
2020-12-31
0000036270
us-gaap:DefinedBenefitPlanEquitySecuritiesMember
2020-12-31
0000036270
us-gaap:CorporateDebtSecuritiesMember
2020-12-31
0000036270
us-gaap:USGovernmentAgenciesDebtSecuritiesMember
2020-12-31
0000036270
us-gaap:ForeignGovernmentDebtSecuritiesMember
2020-12-31
0000036270
mtb:DomesticMutualFundDebtSecuritiesMember
2020-12-31
0000036270
us-gaap:DefinedBenefitPlanDebtSecurityMember
2020-12-31
0000036270
mtb:OtherDiversifiedMutualFundMember
2020-12-31
0000036270
us-gaap:DefinedBenefitPlanRealEstateMember
2020-12-31
0000036270
us-gaap:PrivateEquityFundsMember
2020-12-31
0000036270
us-gaap:HedgeFundsMember
2020-12-31
0000036270
mtb:GuaranteedDepositFundMember
2020-12-31
0000036270
mtb:OtherSecuritiesMember
2020-12-31
0000036270
mtb:MoneyMarketInvestmentsMember
us-gaap:FairValueInputsLevel1Member
2020-12-31
0000036270
us-gaap:FairValueInputsLevel1Member
mtb:MAndTEquitySecuritiesMember
2020-12-31
0000036270
us-gaap:FairValueInputsLevel1Member
us-gaap:DefinedBenefitPlanEquitySecuritiesUsMember
2020-12-31
0000036270
us-gaap:FairValueInputsLevel1Member
us-gaap:DefinedBenefitPlanEquitySecuritiesNonUsMember
2020-12-31
0000036270
us-gaap:FairValueInputsLevel1Member
mtb:DomesticMutualFundEquitySecuritiesMember
2020-12-31
0000036270
us-gaap:FairValueInputsLevel1Member
mtb:InternationalMutualFundEquitySecuritiesMember
2020-12-31
0000036270
us-gaap:DefinedBenefitPlanEquitySecuritiesMember
us-gaap:FairValueInputsLevel1Member
2020-12-31
0000036270
us-gaap:FairValueInputsLevel1Member
mtb:DomesticMutualFundDebtSecuritiesMember
2020-12-31
0000036270
us-gaap:DefinedBenefitPlanDebtSecurityMember
us-gaap:FairValueInputsLevel1Member
2020-12-31
0000036270
us-gaap:FairValueInputsLevel1Member
mtb:OtherDiversifiedMutualFundMember
2020-12-31
0000036270
us-gaap:FairValueInputsLevel1Member
us-gaap:DefinedBenefitPlanRealEstateMember
2020-12-31
0000036270
us-gaap:FairValueInputsLevel1Member
us-gaap:HedgeFundsMember
2020-12-31
0000036270
mtb:OtherSecuritiesMember
us-gaap:FairValueInputsLevel1Member
2020-12-31
0000036270
us-gaap:FairValueInputsLevel1Member
2020-12-31
0000036270
mtb:MoneyMarketInvestmentsMember
us-gaap:FairValueInputsLevel2Member
2020-12-31
0000036270
us-gaap:FairValueInputsLevel2Member
us-gaap:CorporateDebtSecuritiesMember
2020-12-31
0000036270
us-gaap:FairValueInputsLevel2Member
us-gaap:USGovernmentAgenciesDebtSecuritiesMember
2020-12-31
0000036270
us-gaap:FairValueInputsLevel2Member
us-gaap:ForeignGovernmentDebtSecuritiesMember
2020-12-31
0000036270
us-gaap:DefinedBenefitPlanDebtSecurityMember
us-gaap:FairValueInputsLevel2Member
2020-12-31
0000036270
us-gaap:FairValueInputsLevel2Member
2020-12-31
0000036270
us-gaap:FairValueInputsLevel3Member
us-gaap:DefinedBenefitPlanRealEstateMember
2020-12-31
0000036270
us-gaap:FairValueInputsLevel3Member
us-gaap:PrivateEquityFundsMember
2020-12-31
0000036270
us-gaap:FairValueInputsLevel3Member
us-gaap:HedgeFundsMember
2020-12-31
0000036270
us-gaap:FairValueInputsLevel3Member
mtb:GuaranteedDepositFundMember
2020-12-31
0000036270
mtb:OtherSecuritiesMember
us-gaap:FairValueInputsLevel3Member
2020-12-31
0000036270
us-gaap:FairValueInputsLevel3Member
2020-12-31
0000036270
mtb:InvestmentGradeBondsMember
2021-01-01
2021-12-31
0000036270
mtb:InvestmentGradeBondsMember
2020-01-01
2020-12-31
0000036270
mtb:HighYieldingBondsMember
2021-01-01
2021-12-31
0000036270
mtb:HighYieldingBondsMember
2020-01-01
2020-12-31
0000036270
mtb:OtherRealEstatePartnershipsMember
us-gaap:FairValueInputsLevel3Member
2020-12-31
0000036270
mtb:OtherPrivateEquityMember
us-gaap:FairValueInputsLevel3Member
2020-12-31
0000036270
mtb:OtherHedgeFundsMember
us-gaap:FairValueInputsLevel3Member
2020-12-31
0000036270
mtb:OtherRealEstatePartnershipsMember
us-gaap:FairValueInputsLevel3Member
2021-01-01
2021-12-31
0000036270
mtb:OtherPrivateEquityMember
us-gaap:FairValueInputsLevel3Member
2021-01-01
2021-12-31
0000036270
mtb:OtherHedgeFundsMember
us-gaap:FairValueInputsLevel3Member
2021-01-01
2021-12-31
0000036270
mtb:OtherSecuritiesMember
us-gaap:FairValueInputsLevel3Member
2021-01-01
2021-12-31
0000036270
mtb:GuaranteedDepositFundMember
us-gaap:FairValueInputsLevel3Member
2021-01-01
2021-12-31
0000036270
mtb:OtherRealEstatePartnershipsMember
us-gaap:FairValueInputsLevel3Member
2021-12-31
0000036270
mtb:OtherPrivateEquityMember
us-gaap:FairValueInputsLevel3Member
2021-12-31
0000036270
mtb:OtherHedgeFundsMember
us-gaap:FairValueInputsLevel3Member
2021-12-31
0000036270
mtb:SupplementalPensionPlanMember
2021-01-01
2021-12-31
0000036270
mtb:SupplementalPensionPlanMember
2020-01-01
2020-12-31
0000036270
mtb:FederalStateAndLocalTaxMember
2018-12-31
0000036270
mtb:AccruedInterestMember
2018-12-31
0000036270
mtb:UnrecognizedIncomeTaxBenefitsMember
2018-12-31
0000036270
mtb:FederalStateAndLocalTaxMember
2019-01-01
2019-12-31
0000036270
mtb:UnrecognizedIncomeTaxBenefitsMember
2019-01-01
2019-12-31
0000036270
mtb:AccruedInterestMember
2019-01-01
2019-12-31
0000036270
mtb:FederalStateAndLocalTaxMember
2019-12-31
0000036270
mtb:AccruedInterestMember
2019-12-31
0000036270
mtb:UnrecognizedIncomeTaxBenefitsMember
2019-12-31
0000036270
mtb:AccruedInterestMember
2020-01-01
2020-12-31
0000036270
mtb:UnrecognizedIncomeTaxBenefitsMember
2020-01-01
2020-12-31
0000036270
mtb:FederalStateAndLocalTaxMember
2020-01-01
2020-12-31
0000036270
mtb:FederalStateAndLocalTaxMember
2020-12-31
0000036270
mtb:AccruedInterestMember
2020-12-31
0000036270
mtb:UnrecognizedIncomeTaxBenefitsMember
2020-12-31
0000036270
mtb:AccruedInterestMember
2021-01-01
2021-12-31
0000036270
mtb:UnrecognizedIncomeTaxBenefitsMember
2021-01-01
2021-12-31
0000036270
mtb:FederalStateAndLocalTaxMember
2021-01-01
2021-12-31
0000036270
mtb:FederalStateAndLocalTaxMember
2021-12-31
0000036270
mtb:AccruedInterestMember
2021-12-31
0000036270
mtb:UnrecognizedIncomeTaxBenefitsMember
2021-12-31
mtb:State
0000036270
us-gaap:SecuritiesInvestmentMember
2020-12-31
0000036270
us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember
2020-12-31
0000036270
mtb:AccumulatedOtherMember
2020-12-31
0000036270
us-gaap:SecuritiesInvestmentMember
2021-01-01
2021-12-31
0000036270
mtb:AccumulatedOtherMember
2021-01-01
2021-12-31
0000036270
us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember
2021-01-01
2021-12-31
0000036270
us-gaap:SecuritiesInvestmentMember
2021-12-31
0000036270
us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember
2021-12-31
0000036270
mtb:AccumulatedOtherMember
2021-12-31
0000036270
us-gaap:SecuritiesInvestmentMember
2019-12-31
0000036270
us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember
2019-12-31
0000036270
mtb:AccumulatedOtherMember
2019-12-31
0000036270
us-gaap:SecuritiesInvestmentMember
2020-01-01
2020-12-31
0000036270
mtb:AccumulatedOtherMember
2020-01-01
2020-12-31
0000036270
us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember
2020-01-01
2020-12-31
0000036270
mtb:AccumulatedNetUnrealizedInvestmentGainLossAllOtherMember
2018-12-31
0000036270
us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember
2018-12-31
0000036270
mtb:AccumulatedOtherMember
2018-12-31
0000036270
mtb:AccumulatedNetUnrealizedInvestmentGainLossAllOtherMember
2019-01-01
2019-12-31
0000036270
mtb:AccumulatedOtherMember
2019-01-01
2019-12-31
0000036270
us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember
2019-01-01
2019-12-31
0000036270
mtb:AccumulatedNetUnrealizedInvestmentGainLossAllOtherMember
2019-12-31
0000036270
us-gaap:SecuritiesInvestmentMember
2018-12-31
0000036270
mtb:AccumulatedOtherAdjustmentMember
2018-12-31
0000036270
us-gaap:SecuritiesInvestmentMember
2019-01-01
2019-12-31
0000036270
mtb:AccumulatedOtherAdjustmentMember
2019-01-01
2019-12-31
0000036270
mtb:AccumulatedOtherAdjustmentMember
2019-12-31
0000036270
mtb:AccumulatedOtherAdjustmentMember
2020-01-01
2020-12-31
0000036270
mtb:AccumulatedOtherAdjustmentMember
2020-12-31
0000036270
mtb:AccumulatedOtherAdjustmentMember
2021-01-01
2021-12-31
0000036270
mtb:AccumulatedOtherAdjustmentMember
2021-12-31
0000036270
us-gaap:GeographicConcentrationRiskMember
us-gaap:AssetsTotalMember
2021-01-01
2021-12-31
0000036270
us-gaap:GeographicConcentrationRiskMember
us-gaap:SalesRevenueNetMember
2021-01-01
2021-12-31
0000036270
us-gaap:GeographicDistributionForeignMember
2021-12-31
0000036270
us-gaap:GeographicDistributionForeignMember
2020-12-31
0000036270
country:KY
2021-12-31
0000036270
country:KY
2020-12-31
0000036270
country:CA
2021-12-31
0000036270
country:CA
2020-12-31
0000036270
us-gaap:InterestRateSwapMember
2021-01-01
2021-12-31
0000036270
us-gaap:InterestRateSwapMember
2020-01-01
2020-12-31
0000036270
us-gaap:InterestRateSwapMember
2019-01-01
2019-12-31
0000036270
mtb:FixedRateLongTermBorrowingsMember
us-gaap:FairValueHedgingMember
2021-12-31
0000036270
mtb:InterestPaymentsOnVariableRateCommercialRealEstateLoansMember
us-gaap:CashFlowHedgingMember
2021-12-31
0000036270
mtb:FixedRateLongTermBorrowingsMember
us-gaap:FairValueHedgingMember
2020-12-31
0000036270
mtb:InterestPaymentsOnVariableRateCommercialRealEstateLoansMember
us-gaap:CashFlowHedgingMember
2020-12-31
0000036270
us-gaap:FairValueHedgingMember
mtb:FixedRateLongTermBorrowingsMember
2021-01-01
2021-12-31
0000036270
us-gaap:CashFlowHedgingMember
mtb:InterestPaymentsOnVariableRateCommercialRealEstateLoansMember
2021-01-01
2021-12-31
0000036270
us-gaap:FairValueHedgingMember
mtb:FixedRateLongTermBorrowingsMember
2020-01-01
2020-12-31
0000036270
us-gaap:CashFlowHedgingMember
mtb:InterestPaymentsOnVariableRateCommercialRealEstateLoansMember
2020-01-01
2020-12-31
0000036270
us-gaap:FairValueHedgingMember
2021-01-01
2021-12-31
0000036270
us-gaap:FairValueHedgingMember
2020-01-01
2020-12-31
0000036270
us-gaap:CashFlowHedgingMember
2021-01-01
2021-12-31
0000036270
us-gaap:CashFlowHedgingMember
2020-01-01
2020-12-31
0000036270
mtb:ForwardStartingInterestRateSwapAgreementsMember
2021-12-31
0000036270
mtb:ForwardStartingInterestRateSwapAgreementsMember
2021-12-31
0000036270
us-gaap:InterestRateSwapMember
2021-12-31
0000036270
us-gaap:InterestRateContractMember
2021-12-31
0000036270
us-gaap:InterestRateContractMember
2020-12-31
0000036270
mtb:ForeignCurrencyAndOtherOptionAndFuturesContractsMember
2021-12-31
0000036270
mtb:ForeignCurrencyAndOtherOptionAndFuturesContractsMember
2020-12-31
0000036270
us-gaap:InterestRateSwapMember
us-gaap:FairValueHedgingMember
us-gaap:DesignatedAsHedgingInstrumentMember
2021-12-31
0000036270
mtb:CommitmentsToSellRealEstateLoansMember
us-gaap:FairValueHedgingMember
us-gaap:DesignatedAsHedgingInstrumentMember
2021-12-31
0000036270
us-gaap:FairValueHedgingMember
us-gaap:DesignatedAsHedgingInstrumentMember
2021-12-31
0000036270
mtb:MortgageRelatedCommitmentsToOriginateRealEstateLoansForSaleMember
us-gaap:NondesignatedMember
2021-12-31
0000036270
mtb:CommitmentsToSellRealEstateLoansMember
us-gaap:NondesignatedMember
2021-12-31
0000036270
us-gaap:InterestRateContractMember
us-gaap:NondesignatedMember
2021-12-31
0000036270
mtb:ForeignExchangeAndOtherOptionAndFuturesContractsMember
us-gaap:NondesignatedMember
2021-12-31
0000036270
us-gaap:NondesignatedMember
2021-12-31
0000036270
us-gaap:InterestRateSwapMember
us-gaap:FairValueHedgingMember
us-gaap:DesignatedAsHedgingInstrumentMember
2020-12-31
0000036270
mtb:CommitmentsToSellRealEstateLoansMember
us-gaap:FairValueHedgingMember
us-gaap:DesignatedAsHedgingInstrumentMember
2020-12-31
0000036270
us-gaap:FairValueHedgingMember
us-gaap:DesignatedAsHedgingInstrumentMember
2020-12-31
0000036270
mtb:MortgageRelatedCommitmentsToOriginateRealEstateLoansForSaleMember
us-gaap:NondesignatedMember
2020-12-31
0000036270
mtb:CommitmentsToSellRealEstateLoansMember
us-gaap:NondesignatedMember
2020-12-31
0000036270
us-gaap:InterestRateContractMember
us-gaap:NondesignatedMember
2020-12-31
0000036270
mtb:ForeignExchangeAndOtherOptionAndFuturesContractsMember
us-gaap:NondesignatedMember
2020-12-31
0000036270
us-gaap:NondesignatedMember
2020-12-31
0000036270
us-gaap:InterestRateSwapMember
mtb:FixedRateLongTermBorrowingsMember
us-gaap:DesignatedAsHedgingInstrumentMember
us-gaap:FairValueHedgingMember
2021-01-01
2021-12-31
0000036270
us-gaap:InterestRateSwapMember
mtb:FixedRateLongTermBorrowingsMember
us-gaap:DesignatedAsHedgingInstrumentMember
us-gaap:FairValueHedgingMember
2020-01-01
2020-12-31
0000036270
us-gaap:InterestRateSwapMember
mtb:FixedRateLongTermBorrowingsMember
us-gaap:DesignatedAsHedgingInstrumentMember
us-gaap:FairValueHedgingMember
2019-01-01
2019-12-31
0000036270
us-gaap:InterestRateContractMember
2021-01-01
2021-12-31
0000036270
us-gaap:InterestRateContractMember
2020-01-01
2020-12-31
0000036270
us-gaap:InterestRateContractMember
2019-01-01
2019-12-31
0000036270
mtb:ForeignExchangeAndOtherOptionAndFuturesContractsMember
2021-01-01
2021-12-31
0000036270
mtb:ForeignExchangeAndOtherOptionAndFuturesContractsMember
2020-01-01
2020-12-31
0000036270
mtb:ForeignExchangeAndOtherOptionAndFuturesContractsMember
2019-01-01
2019-12-31
0000036270
us-gaap:DesignatedAsHedgingInstrumentMember
us-gaap:CarryingReportedAmountFairValueDisclosureMember
us-gaap:LongTermDebtMember
2021-12-31
0000036270
us-gaap:DesignatedAsHedgingInstrumentMember
us-gaap:CarryingReportedAmountFairValueDisclosureMember
us-gaap:LongTermDebtMember
2020-12-31
0000036270
us-gaap:DesignatedAsHedgingInstrumentMember
us-gaap:EstimateOfFairValueFairValueDisclosureMember
us-gaap:LongTermDebtMember
2021-12-31
0000036270
us-gaap:DesignatedAsHedgingInstrumentMember
us-gaap:EstimateOfFairValueFairValueDisclosureMember
us-gaap:LongTermDebtMember
2020-12-31
0000036270
us-gaap:InterestIncomeMember
2021-12-31
0000036270
us-gaap:InterestIncomeMember
2020-12-31
0000036270
us-gaap:InterestRateSwapMember
mtb:MaturityPeriodTwoMember
2021-01-01
2021-12-31
0000036270
us-gaap:InterestRateSwapMember
mtb:MaturityPeriodThreeMember
2021-01-01
2021-12-31
0000036270
mtb:CounterpartiesMember
2021-12-31
0000036270
mtb:CounterpartiesMember
2020-12-31
0000036270
mtb:ClearinghouseCreditFacilitiesMember
2021-12-31
0000036270
mtb:ClearinghouseCreditFacilitiesMember
2020-12-31
0000036270
us-gaap:VariableInterestEntityPrimaryBeneficiaryMember
2021-12-31
0000036270
us-gaap:VariableInterestEntityPrimaryBeneficiaryMember
2020-12-31
0000036270
us-gaap:FairValueMeasurementsRecurringMember
2021-12-31
0000036270
us-gaap:FairValueMeasurementsRecurringMember
us-gaap:FairValueInputsLevel1Member
2021-12-31
0000036270
us-gaap:FairValueMeasurementsRecurringMember
us-gaap:FairValueInputsLevel2Member
2021-12-31
0000036270
us-gaap:USTreasuryAndGovernmentMember
us-gaap:FairValueMeasurementsRecurringMember
2021-12-31
0000036270
us-gaap:USTreasuryAndGovernmentMember
us-gaap:FairValueMeasurementsRecurringMember
us-gaap:FairValueInputsLevel2Member
2021-12-31
0000036270
us-gaap:OtherDebtSecuritiesMember
us-gaap:FairValueMeasurementsRecurringMember
2021-12-31
0000036270
us-gaap:OtherDebtSecuritiesMember
us-gaap:FairValueMeasurementsRecurringMember
us-gaap:FairValueInputsLevel2Member
2021-12-31
0000036270
us-gaap:FairValueMeasurementsRecurringMember
us-gaap:FairValueInputsLevel3Member
2021-12-31
0000036270
us-gaap:FairValueMeasurementsRecurringMember
2020-12-31
0000036270
us-gaap:FairValueMeasurementsRecurringMember
us-gaap:FairValueInputsLevel1Member
2020-12-31
0000036270
us-gaap:FairValueMeasurementsRecurringMember
us-gaap:FairValueInputsLevel2Member
2020-12-31
0000036270
us-gaap:USTreasuryAndGovernmentMember
us-gaap:FairValueMeasurementsRecurringMember
2020-12-31
0000036270
us-gaap:USTreasuryAndGovernmentMember
us-gaap:FairValueMeasurementsRecurringMember
us-gaap:FairValueInputsLevel2Member
2020-12-31
0000036270
mtb:MortgageBackedSecuritiesIssuedByPrivateEnterprisesResidentialMember
us-gaap:FairValueMeasurementsRecurringMember
2020-12-31
0000036270
mtb:MortgageBackedSecuritiesIssuedByPrivateEnterprisesResidentialMember
us-gaap:FairValueMeasurementsRecurringMember
us-gaap:FairValueInputsLevel3Member
2020-12-31
0000036270
us-gaap:OtherDebtSecuritiesMember
us-gaap:FairValueMeasurementsRecurringMember
2020-12-31
0000036270
us-gaap:OtherDebtSecuritiesMember
us-gaap:FairValueMeasurementsRecurringMember
us-gaap:FairValueInputsLevel2Member
2020-12-31
0000036270
us-gaap:FairValueMeasurementsRecurringMember
us-gaap:FairValueInputsLevel3Member
2020-12-31
0000036270
us-gaap:FairValueMeasurementsRecurringMember
us-gaap:FairValueInputsLevel3Member
us-gaap:MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember
2020-12-31
0000036270
us-gaap:FairValueMeasurementsRecurringMember
us-gaap:FairValueInputsLevel3Member
mtb:OtherAssetsAndOtherLiabilitiesMember
2020-12-31
0000036270
us-gaap:FairValueMeasurementsRecurringMember
us-gaap:FairValueInputsLevel3Member
mtb:OtherAssetsAndOtherLiabilitiesMember
2021-01-01
2021-12-31
0000036270
us-gaap:FairValueMeasurementsRecurringMember
us-gaap:FairValueInputsLevel3Member
us-gaap:MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember
2021-01-01
2021-12-31
0000036270
us-gaap:FairValueMeasurementsRecurringMember
us-gaap:FairValueInputsLevel3Member
mtb:OtherAssetsAndOtherLiabilitiesMember
2021-12-31
0000036270
us-gaap:FairValueMeasurementsRecurringMember
us-gaap:FairValueInputsLevel3Member
us-gaap:MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember
2019-12-31
0000036270
us-gaap:FairValueMeasurementsRecurringMember
us-gaap:FairValueInputsLevel3Member
mtb:OtherAssetsAndOtherLiabilitiesMember
2019-12-31
0000036270
us-gaap:FairValueMeasurementsRecurringMember
us-gaap:FairValueInputsLevel3Member
mtb:OtherAssetsAndOtherLiabilitiesMember
2020-01-01
2020-12-31
0000036270
us-gaap:FairValueMeasurementsRecurringMember
us-gaap:FairValueInputsLevel3Member
us-gaap:MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember
2018-12-31
0000036270
us-gaap:FairValueMeasurementsRecurringMember
us-gaap:FairValueInputsLevel3Member
mtb:OtherAssetsAndOtherLiabilitiesMember
2018-12-31
0000036270
us-gaap:FairValueMeasurementsRecurringMember
us-gaap:FairValueInputsLevel3Member
mtb:OtherAssetsAndOtherLiabilitiesMember
2019-01-01
2019-12-31
0000036270
us-gaap:FairValueMeasurementsRecurringMember
us-gaap:FairValueInputsLevel3Member
us-gaap:MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember
2019-01-01
2019-12-31
0000036270
us-gaap:FairValueMeasurementsNonrecurringMember
2021-12-31
0000036270
us-gaap:FairValueMeasurementsNonrecurringMember
2020-12-31
0000036270
us-gaap:FairValueMeasurementsNonrecurringMember
2019-12-31
0000036270
us-gaap:FairValueInputsLevel2Member
us-gaap:FairValueMeasurementsNonrecurringMember
2021-12-31
0000036270
us-gaap:FairValueInputsLevel2Member
us-gaap:FairValueMeasurementsNonrecurringMember
2020-12-31
0000036270
us-gaap:FairValueInputsLevel2Member
us-gaap:FairValueMeasurementsNonrecurringMember
2019-12-31
0000036270
us-gaap:FairValueInputsLevel3Member
us-gaap:FairValueMeasurementsNonrecurringMember
2021-12-31
0000036270
us-gaap:FairValueInputsLevel3Member
us-gaap:FairValueMeasurementsNonrecurringMember
2020-12-31
0000036270
us-gaap:FairValueInputsLevel3Member
us-gaap:FairValueMeasurementsNonrecurringMember
2019-12-31
0000036270
us-gaap:FairValueInputsLevel3Member
2021-01-01
2021-12-31
0000036270
us-gaap:FairValueInputsLevel3Member
2020-01-01
2020-12-31
0000036270
us-gaap:FairValueInputsLevel3Member
2019-01-01
2019-12-31
0000036270
us-gaap:FairValueInputsLevel3Member
us-gaap:ResidentialMortgageMember
2021-12-31
0000036270
us-gaap:FairValueInputsLevel3Member
us-gaap:ResidentialMortgageMember
2020-12-31
0000036270
us-gaap:FairValueInputsLevel3Member
us-gaap:ResidentialMortgageMember
2021-01-01
2021-12-31
0000036270
us-gaap:FairValueInputsLevel3Member
us-gaap:ResidentialMortgageMember
2020-01-01
2020-12-31
0000036270
us-gaap:FairValueInputsLevel3Member
us-gaap:ResidentialMortgageMember
2019-01-01
2019-12-31
0000036270
mtb:DiscountedCashFlowsMember
mtb:OtherAssetsAndOtherLiabilitiesMember
us-gaap:FairValueMeasurementsRecurringMember
2021-12-31
0000036270
mtb:TwoIndependentPricingQuotesMember
us-gaap:MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember
us-gaap:FairValueMeasurementsRecurringMember
2020-12-31
0000036270
mtb:DiscountedCashFlowsMember
mtb:OtherAssetsAndOtherLiabilitiesMember
us-gaap:FairValueMeasurementsRecurringMember
2020-12-31
0000036270
mtb:DiscountedCashFlowsMember
mtb:OtherAssetsAndOtherLiabilitiesMember
srt:MinimumMember
us-gaap:FairValueMeasurementsRecurringMember
2021-01-01
2021-12-31
0000036270
mtb:DiscountedCashFlowsMember
mtb:OtherAssetsAndOtherLiabilitiesMember
srt:MaximumMember
us-gaap:FairValueMeasurementsRecurringMember
2021-01-01
2021-12-31
0000036270
mtb:DiscountedCashFlowsMember
mtb:OtherAssetsAndOtherLiabilitiesMember
srt:WeightedAverageMember
us-gaap:FairValueMeasurementsRecurringMember
2021-01-01
2021-12-31
0000036270
mtb:DiscountedCashFlowsMember
mtb:OtherAssetsAndOtherLiabilitiesMember
srt:MinimumMember
us-gaap:FairValueMeasurementsRecurringMember
2020-01-01
2020-12-31
0000036270
mtb:DiscountedCashFlowsMember
mtb:OtherAssetsAndOtherLiabilitiesMember
srt:MaximumMember
us-gaap:FairValueMeasurementsRecurringMember
2020-01-01
2020-12-31
0000036270
mtb:DiscountedCashFlowsMember
mtb:OtherAssetsAndOtherLiabilitiesMember
srt:WeightedAverageMember
us-gaap:FairValueMeasurementsRecurringMember
2020-01-01
2020-12-31
0000036270
us-gaap:CarryingReportedAmountFairValueDisclosureMember
2021-12-31
0000036270
us-gaap:EstimateOfFairValueFairValueDisclosureMember
2021-12-31
0000036270
mtb:CommercialLoansAndLeasesMember
us-gaap:CarryingReportedAmountFairValueDisclosureMember
2021-12-31
0000036270
mtb:CommercialLoansAndLeasesMember
us-gaap:EstimateOfFairValueFairValueDisclosureMember
2021-12-31
0000036270
mtb:CommercialLoansAndLeasesMember
us-gaap:FairValueInputsLevel3Member
2021-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
us-gaap:CarryingReportedAmountFairValueDisclosureMember
2021-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
us-gaap:EstimateOfFairValueFairValueDisclosureMember
2021-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
us-gaap:FairValueInputsLevel2Member
2021-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
us-gaap:FairValueInputsLevel3Member
2021-12-31
0000036270
mtb:ResidentialRealEstateLoansMember
us-gaap:CarryingReportedAmountFairValueDisclosureMember
2021-12-31
0000036270
mtb:ResidentialRealEstateLoansMember
us-gaap:EstimateOfFairValueFairValueDisclosureMember
2021-12-31
0000036270
mtb:ResidentialRealEstateLoansMember
us-gaap:FairValueInputsLevel2Member
2021-12-31
0000036270
mtb:ResidentialRealEstateLoansMember
us-gaap:FairValueInputsLevel3Member
2021-12-31
0000036270
us-gaap:CarryingReportedAmountFairValueDisclosureMember
2020-12-31
0000036270
us-gaap:EstimateOfFairValueFairValueDisclosureMember
2020-12-31
0000036270
mtb:CommercialLoansAndLeasesMember
us-gaap:CarryingReportedAmountFairValueDisclosureMember
2020-12-31
0000036270
mtb:CommercialLoansAndLeasesMember
us-gaap:EstimateOfFairValueFairValueDisclosureMember
2020-12-31
0000036270
mtb:CommercialLoansAndLeasesMember
us-gaap:FairValueInputsLevel3Member
2020-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
us-gaap:CarryingReportedAmountFairValueDisclosureMember
2020-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
us-gaap:EstimateOfFairValueFairValueDisclosureMember
2020-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
us-gaap:FairValueInputsLevel2Member
2020-12-31
0000036270
mtb:CommercialRealEstateExcludingResidentialBuilderAndDeveloperAndOtherConstructionMember
us-gaap:FairValueInputsLevel3Member
2020-12-31
0000036270
mtb:ResidentialRealEstateLoansMember
us-gaap:CarryingReportedAmountFairValueDisclosureMember
2020-12-31
0000036270
mtb:ResidentialRealEstateLoansMember
us-gaap:EstimateOfFairValueFairValueDisclosureMember
2020-12-31
0000036270
mtb:ResidentialRealEstateLoansMember
us-gaap:FairValueInputsLevel2Member
2020-12-31
0000036270
mtb:ResidentialRealEstateLoansMember
us-gaap:FairValueInputsLevel3Member
2020-12-31
0000036270
mtb:BusinessBankingMember
us-gaap:OperatingSegmentsMember
2021-01-01
2021-12-31
0000036270
mtb:BusinessBankingMember
us-gaap:OperatingSegmentsMember
2020-01-01
2020-12-31
0000036270
mtb:BusinessBankingMember
us-gaap:OperatingSegmentsMember
2019-01-01
2019-12-31
0000036270
mtb:CommercialBankingMember
us-gaap:OperatingSegmentsMember
2021-01-01
2021-12-31
0000036270
mtb:CommercialBankingMember
us-gaap:OperatingSegmentsMember
2020-01-01
2020-12-31
0000036270
mtb:CommercialBankingMember
us-gaap:OperatingSegmentsMember
2019-01-01
2019-12-31
0000036270
mtb:CommercialRealEstateSegmentMember
us-gaap:OperatingSegmentsMember
2021-01-01
2021-12-31
0000036270
mtb:CommercialRealEstateSegmentMember
us-gaap:OperatingSegmentsMember
2020-01-01
2020-12-31
0000036270
mtb:CommercialRealEstateSegmentMember
us-gaap:OperatingSegmentsMember
2019-01-01
2019-12-31
0000036270
mtb:DiscretionaryPortfolioMember
us-gaap:OperatingSegmentsMember
2021-01-01
2021-12-31
0000036270
mtb:DiscretionaryPortfolioMember
us-gaap:OperatingSegmentsMember
2020-01-01
2020-12-31
0000036270
mtb:DiscretionaryPortfolioMember
us-gaap:OperatingSegmentsMember
2019-01-01
2019-12-31
0000036270
mtb:ResidentialMortgageBankingMember
us-gaap:OperatingSegmentsMember
2021-01-01
2021-12-31
0000036270
mtb:ResidentialMortgageBankingMember
us-gaap:OperatingSegmentsMember
2020-01-01
2020-12-31
0000036270
mtb:ResidentialMortgageBankingMember
us-gaap:OperatingSegmentsMember
2019-01-01
2019-12-31
0000036270
mtb:RetailBankingMember
us-gaap:OperatingSegmentsMember
2021-01-01
2021-12-31
0000036270
mtb:RetailBankingMember
us-gaap:OperatingSegmentsMember
2020-01-01
2020-12-31
0000036270
mtb:RetailBankingMember
us-gaap:OperatingSegmentsMember
2019-01-01
2019-12-31
0000036270
us-gaap:CorporateNonSegmentMember
2021-01-01
2021-12-31
0000036270
us-gaap:CorporateNonSegmentMember
2020-01-01
2020-12-31
0000036270
us-gaap:CorporateNonSegmentMember
2019-01-01
2019-12-31
0000036270
us-gaap:IntersegmentEliminationMember
2021-01-01
2021-12-31
0000036270
us-gaap:IntersegmentEliminationMember
2020-01-01
2020-12-31
0000036270
us-gaap:IntersegmentEliminationMember
2019-01-01
2019-12-31
0000036270
srt:ParentCompanyMember
2021-12-31
0000036270
srt:SubsidiariesMember
2021-12-31
0000036270
mtb:MAndTMember
2021-12-31
0000036270
mtb:WilmingtonTrustNaMember
2021-12-31
0000036270
mtb:MAndTMember
2020-12-31
0000036270
mtb:MAndTBankMember
2020-12-31
0000036270
mtb:WilmingtonTrustNaMember
2020-12-31
0000036270
mtb:BayviewLendingGroupMember
2021-12-31
0000036270
mtb:BayviewLendingGroupMember
mtb:OtherRevenuesFromOperationsMember
2021-01-01
2021-12-31
0000036270
mtb:BayviewLendingGroupMember
mtb:OtherRevenuesFromOperationsMember
2020-01-01
2020-12-31
0000036270
mtb:BayviewLendingGroupMember
mtb:OtherRevenuesFromOperationsMember
2019-01-01
2019-12-31
0000036270
mtb:BayviewLendingGroupAndBayviewFinancialMember
2021-12-31
0000036270
mtb:BayviewLendingGroupAndBayviewFinancialMember
2020-12-31
0000036270
mtb:BayviewLendingGroupAndBayviewFinancialMember
2021-01-01
2021-12-31
0000036270
mtb:BayviewLendingGroupAndBayviewFinancialMember
2020-01-01
2020-12-31
0000036270
mtb:BayviewLendingGroupAndBayviewFinancialMember
2019-01-01
2019-12-31
0000036270
mtb:BayviewFinancialMember
2021-12-31
0000036270
mtb:BayviewFinancialMember
2020-12-31
0000036270
mtb:BayviewFinancialMember
2021-01-01
2021-12-31
0000036270
mtb:BayviewFinancialMember
2020-01-01
2020-12-31
0000036270
mtb:BayviewFinancialMember
2019-01-01
2019-12-31
0000036270
mtb:BayviewFinancialMember
mtb:SyndicatedLoanFacilityMember
2021-12-31
0000036270
mtb:BayviewFinancialMember
mtb:SyndicatedLoanFacilityMember
us-gaap:ParentMember
2021-12-31
0000036270
mtb:BayviewFinancialMember
us-gaap:FederalHousingAdministrationLoanMember
2021-12-31
0000036270
srt:ParentCompanyMember
2020-12-31
0000036270
srt:ParentCompanyMember
2021-01-01
2021-12-31
0000036270
srt:ParentCompanyMember
2020-01-01
2020-12-31
0000036270
srt:ParentCompanyMember
2019-01-01
2019-12-31
0000036270
srt:ParentCompanyMember
mtb:SeriesIAndSeriesGPreferredStockMember
2021-01-01
2021-12-31
0000036270
srt:ParentCompanyMember
mtb:SeriesIAndSeriesGPreferredStockMember
2019-01-01
2019-12-31
0000036270
srt:ParentCompanyMember
2019-12-31
0000036270
srt:ParentCompanyMember
2018-12-31
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 |