XML 64 R53.htm IDEA: XBRL DOCUMENT
v3.25.2

Loans and allowance for loan losses - Summary of Payment Status of Loans Modified (Detail) - USD ($) $ in Thousands | Jun. 30, 2025 | Jun. 30, 2024
--- | --- | ---
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | $ 1,466,000 | $ 1,482,000
Guaranteed by Government-Related Entities |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Modified past due 30-89 days | 40,000 | 45,000
Modified past due 90 days or more | 35,000 | 27,000
Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 1,247,000 | 1,323,000
30-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 109,000 | 113,000
Accruing Loans Past Due 90 Days or More |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 110,000 | 46,000
Commercial and industrial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 351,000 | 312,000
Commercial and industrial | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 281,000 | 294,000
Commercial and industrial | 30-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 7,000 | 15,000
Commercial and industrial | Accruing Loans Past Due 90 Days or More |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 63,000 | 3,000
Commercial Real Estate | Commercial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 653,000 | 601,000
Commercial Real Estate | Commercial | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 598,000 | 545,000
Commercial Real Estate | Commercial | 30-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 54,000 | 42,000
Commercial Real Estate | Commercial | Accruing Loans Past Due 90 Days or More |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 1,000 | 14,000
Commercial Real Estate | Residential builder and developer |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 0 | 28,000
Commercial Real Estate | Residential builder and developer | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 0 | 28,000
Commercial Real Estate | Residential builder and developer | 30-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 0 | 0
Commercial Real Estate | Residential builder and developer | Accruing Loans Past Due 90 Days or More |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 0 | 0
Commercial Real Estate | Other commercial construction |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 284,000 | 346,000
Commercial Real Estate | Other commercial construction | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 279,000 | 344,000
Commercial Real Estate | Other commercial construction | 30-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 0 | 2,000
Commercial Real Estate | Other commercial construction | Accruing Loans Past Due 90 Days or More |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 5,000 | 0
Residential Real Estate | Residential |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 166,000 | 193,000
Residential Real Estate | Residential | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 77,000 | 110,000
Residential Real Estate | Residential | 30-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 48,000 | 54,000
Residential Real Estate | Residential | Accruing Loans Past Due 90 Days or More |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 41,000 | 29,000
Consumer | Home equity lines and loans |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 1,000 | 2,000
Consumer | Home equity lines and loans | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 1,000 | 2,000
Consumer | Home equity lines and loans | 30-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 0 | 0
Consumer | Home equity lines and loans | Accruing Loans Past Due 90 Days or More |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 0 | 0
Consumer | Recreational finance |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 1,000 | 0
Consumer | Recreational finance | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 1,000 | 0
Consumer | Recreational finance | 30-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 0 | 0
Consumer | Recreational finance | Accruing Loans Past Due 90 Days or More |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 0 | 0
Consumer | Automobile |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 0 | 0
Consumer | Automobile | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 0 | 0
Consumer | Automobile | 30-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 0 | 0
Consumer | Automobile | Accruing Loans Past Due 90 Days or More |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 0 | 0
Consumer | Other |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 10,000 | 0
Consumer | Other | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 10,000 | 0
Consumer | Other | 30-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | 0 | 0
Consumer | Other | Accruing Loans Past Due 90 Days or More |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost | $ 0 | $ 0

X
- Definition Delinquency status of loans and leases receivable modified past due ninety days or more. + References No definition available. + Details
Name: | mtb_DelinquencyStatusOfLoansAndLeasesReceivableModifiedPastDueNinetyDaysOrMore
Namespace Prefix: | mtb_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Delinquency status of loans and leases receivable modified past due thirty to eighty nine days. + References No definition available. + Details
Name: | mtb_DelinquencyStatusOfLoansAndLeasesReceivableModifiedPastDueThirtyToEightyNineDays
Namespace Prefix: | mtb_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 310 -SubTopic 20 -Name Accounting Standards Codification -Section 40 -Paragraph 7 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481628/310-20-40-7 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 + Details
Name: | us-gaap_AccountsNotesAndLoansReceivableLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amortized cost excluding accrued interest, of financing receivable 12 months after modification for debtor experiencing financial difficulty. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 42 -Subparagraph (a)(3) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481962/310-10-50-42 + Details
Name: | us-gaap_FinancingReceivableExcludingAccruedInterestModifiedPast12Months
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_LoansInsuredOrGuaranteedByGovernmentAuthoritiesAxis=us-gaap_LoansInsuredOrGuaranteedByUsGovernmentAuthoritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablesPeriodPastDueAxis=us-gaap_FinancialAssetNotPastDueMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablesPeriodPastDueAxis=us-gaap_FinancingReceivables30To59DaysPastDueMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablesPeriodPastDueAxis=us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=mtb_CommercialFinancialLeasingMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_CommercialRealEstatePortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

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

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

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_ResidentialPortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_ConsumerPortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

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

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

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