XML 54 R46.htm IDEA: XBRL DOCUMENT
v3.24.1.u1

Loans and Leases and the Allowance for Credit Losses - Additional Information (Detail) - USD ($) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2024 | Mar. 31, 2023 | Dec. 31, 2023
Loans And Leases Receivable [Line Items] |  |  |
Amount of foreclosed residential real estate property held | $ 38 |  | $ 39
Loans secured by residential real estate that were in the process of foreclosure | $ 165 |  | 170
Percentage loans in the process of foreclosure, serviced by other entities, classified as government guaranteed | 35.00% |  |
Minimum [Member] |  |  |
Loans And Leases Receivable [Line Items] |  |  |
Loan delinquent period | 90 days |  |
Maximum [Member] |  |  |
Loans And Leases Receivable [Line Items] |  |  |
Loan delinquent period | 150 days |  |
Commercial and Industrial [Member] |  |  |
Loans And Leases Receivable [Line Items] |  |  |
Weighted-average remaining term | 8 months 12 days | 1 year 2 months 12 days |
Commercial Real Estate Loans [Member] |  |  |
Loans And Leases Receivable [Line Items] |  |  |
Weighted-average remaining term | 9 months 18 days | 1 year 2 months 12 days |
Commercial Loans and Commercial Real Estate [Member] | Minimum [Member] |  |  |
Loans And Leases Receivable [Line Items] |  |  |
Amount of real estate loan as reported as accruing or nonaccruing | $ 5 |  |
Residential Real Estate Loans [Member] |  |  |
Loans And Leases Receivable [Line Items] |  |  |
Weighted-average remaining term | 11 years 4 months 24 days | 9 years 1 month 6 days |
Commercial and Industrial Loans [Member] | Asset Pledged as Collateral without Right [Member] | FHLBs Facility [Member] |  |  |
Loans And Leases Receivable [Line Items] |  |  |
Pledged financial instruments | $ 14,900 |  | 13,400
Residential Mortgage Loans [Member] | Asset Pledged as Collateral without Right [Member] | FHLBs Facility [Member] |  |  |
Loans And Leases Receivable [Line Items] |  |  |
Pledged financial instruments | 18,600 |  | 18,800
Commercial Real Estate Loans [Member] | Asset Pledged as Collateral without Right [Member] | FHLBs Facility [Member] |  |  |
Loans And Leases Receivable [Line Items] |  |  |
Pledged financial instruments | 16,200 |  | 16,400
Home Equity Loans and Lines of Credit [Member] | Asset Pledged as Collateral without Right [Member] | FHLBs Facility [Member] |  |  |
Loans And Leases Receivable [Line Items] |  |  |
Pledged financial instruments | 2,600 |  | 2,600
Other Consumer Loans [Member] | Asset Pledged as Collateral without Right [Member] | FHLBs Facility [Member] |  |  |
Loans And Leases Receivable [Line Items] |  |  |
Pledged financial instruments | $ 10,900 |  | $ 11,000

X
- Definition Financing receivable recorded investment accrual or nonaccrual status. + References No definition available. + Details
Name: | mtb_FinancingReceivableRecordedInvestmentAccrualOrNonaccrualStatus
Namespace Prefix: | mtb_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The threshold number of days in delinquency at which criticized loans are generally classified as non-accrual. + References No definition available. + Details
Name: | mtb_LoanDelinquentPeriodForNonAccrualStatusClassification
Namespace Prefix: | mtb_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Loans and leases receivable. + References No definition available. + Details
Name: | mtb_LoansAndLeasesReceivableLineItems
Namespace Prefix: | mtb_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Loans and leases weighted-average remaining term + References No definition available. + Details
Name: | mtb_LoansAndLeasesWeightedAverageRemainingTerm
Namespace Prefix: | mtb_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of loans in the process of foreclosure, serviced by other entities, classified as government guaranteed. + References No definition available. + Details
Name: | mtb_PercentageOfLoansInTheProcessOfForeclosureServicedByOtherEntitiesClassifiedAsGovernmentGuaranteed
Namespace Prefix: | mtb_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Residential mortgage loans secured by residential real estate in process of foreclosure. + References No definition available. + Details
Name: | mtb_ResidentialMortgageLoansSecuredByResidentialRealEstateInProcessOfForeclosure
Namespace Prefix: | mtb_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amortized cost, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.6-04(5)(b)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479617/946-210-S99-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481990/310-10-45-2 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479319/326-20-50-5 + Details
Name: | us-gaap_NotesReceivableNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Carrying amount as of the balance sheet date of other real estate and foreclosed assets. Other real estate may include real estate investments, real estate loans that qualify as investments in real estate, and premises that are no longer used in operations may also be included in real estate owned. Foreclosed assets include all assets obtained in full or partial satisfaction of a debt arrangement through foreclosure proceedings. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.10(4)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1 + Details
Name: | us-gaap_OtherRealEstateAndForeclosedAssets
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | srt_RangeAxis=srt_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=mtb_CommercialAndIndustrialMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=mtb_CommercialRealEstateLoansMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=mtb_CommercialLoansAndCommercialRealEstateMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=mtb_ResidentialRealEstateLoansMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=mtb_CommercialAndIndustrialLoansMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PledgedStatusAxis=us-gaap_AssetPledgedAsCollateralWithoutRightMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PledgingPurposeAxis=us-gaap_FederalHomeLoanBankAdvancesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=us-gaap_ResidentialMortgageMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=us-gaap_RealEstateLoanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=us-gaap_HomeEquityMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=mtb_OtherConsumerLoansMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |