Adjustments to reconcile net income to net cash provided by operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Commercial Commercial Real Estate Excluding Residential Builder And Developer And Other Construction [Member] Commercial real estate excluding residential builder and developer and other construction. Payments on long-term borrowings Repayments of Long-Term Debt Cover [Abstract] Cover [Abstract] Derivatives not designated as hedging instruments, derivatives Gain (Loss) on Derivative Instruments Held for Trading Purposes, Net Trading Symbol Trading Symbol Ownership percentage (as a percent) Equity Method Investment, Ownership Percentage Fair value hedges: Fair Value Hedging [Member] Preferred Series F Series F Preferred Stock [Member] Other residential real estate Commitments To Extend Credit For Other Residential Real Estate Commitments to extend credit for other residential real estate. Debt Instrument, Redemption, Period Debt Instrument, Redemption, Period [Axis] Pledged Status [Domain] Pledged Status [Domain] Asset derivatives, fair value Derivative Asset, Subject to Master Netting Arrangement, before Offset Non-NEOs Non-NEOs [Member] Long-term debt term (in years) Long-Term Debt, Term Common stock per share dividend amount (in USD per share) Common Stock, Dividends, Per Share, Declared M&T Bank M&T Bank [Member] M&T Bank Mortgage loans held for sale Financing Receivable, Held-for-Sale, Not Part of Disposal Group, after Valuation Allowance Maturity Period 2026 Maturity Period Two [Member] Maturity Period Two [Member]. Debt Instrument, Redemption, Period Debt Instrument, Redemption, Period [Domain] Debt securities held to maturity: Debt Securities, Held-to-Maturity, Fair Value, Maturity [Abstract] Non-Rule 10b5-1 Arrangement Adopted Non-Rule 10b5-1 Arrangement Adopted [Flag] Hedging Relationship Hedging Relationship [Domain] Fair value measurements Fair Value Disclosures [Text Block] Award Timing Disclosures [Line Items] Financial Asset, Aging [Axis] Financial Asset, Aging [Axis] Investment, Name Investment, Name [Domain] Derivatives in fair value hedging relationships, derivative Derivative, Gain (Loss) on Derivative, Net Changes in Allowance for Credit Losses Financing Receivable, Allowance for Credit Loss [Table Text Block] Financing Receivable, Past Due [Table] Financing Receivable, Past Due [Table] Fair Value Measurements Portion at Fair Value Measurement [Member] Debt Securities, Held-to-Maturity [Table] Debt Securities, Held-to-Maturity [Table] Net interest income Net Interest Income Interest Income (Expense), Operating Residential builder and developer Residential Builder And Developer [Member] Residential builder and developer. Revenue from Contract with Customer [Abstract] Revenue from Contract with Customer [Abstract] Real estate acquired in settlement of loans Real Estate Owned, Transfer to Real Estate Owned Pledged Status [Axis] Pledged Status [Axis] Prior Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year Total debt securities Gross unrealized losses Investment In Debt Securities Gross Unrealized Losses Investment in debt securities gross unrealized losses. Operating Segments Operating Segments [Member] Class of Financing Receivable [Domain] Class of Financing Receivable [Domain] Criticized accrual Criticized Accrual [Member] Criticized accrual. Net cash provided by operating activities Net Cash Provided by (Used in) Operating Activities Cash flows from operating activities Net Cash Provided by (Used in) Operating Activities [Abstract] Accumulated Other Comprehensive Income (Loss), Net Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Secured Debt Secured Debt [Member] Award Timing Method Award Timing Method [Text Block] Net periodic benefit Defined Benefit Plan, Net Periodic Benefit Cost (Credit) Total available for sale (amortized cost) Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Amortized Cost Trading Arrangements, by Individual Trading Arrangements, by Individual [Table] Measurement Frequency Measurement Frequency [Axis] Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Loans and leases (a) Total (a) (b) Total (a) (b) Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss, Fee, and Loan in Process Insider Trading Policies and Procedures [Line Items] Indirect expense Indirect Expense (Income) Indirect Expense (Income) State and political subdivisions US States and Political Subdivisions Debt Securities [Member] Amounts reclassified from accumulated other comprehensive income that (increase) decrease net income: Reclassification from AOCI, Current Period, before Tax, Attributable to Parent Adjustment to Compensation, Amount Adjustment to Compensation Amount Compensation Amount Outstanding Recovery Compensation Amount Term Extension Payment Deferral [Member] Aggregate Change in Present Value of Accumulated Benefit for All Pension Plans Reported in Summary Compensation Table Aggregate Change in Present Value of Accumulated Benefit for All Pension Plans Reported in Summary Compensation Table [Member] Entity Small Business Entity Small Business Company Selected Measure Amount Company Selected Measure Amount Revolving Loans Converted to Term Loans Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan Tabular List, Table Tabular List [Table Text Block] FHLB of New York FHLB of New York [Member] FHLB of New York. Level 3 Fair Value, Inputs, Level 3 [Member] Loans And Leases Receivable [Line Items] Loans And Leases Receivable [Line Items] Loans and leases receivable. Antidilutive securities excluded from computation of earnings per share Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Other expense Noninterest Expense [Abstract] Revolving Loans Financing Receivable, Excluding Accrued Interest, Revolving Credit Facility Credit Facility [Domain] Amortized cost Financing Receivable, Excluding Accrued Interest, Modified, after 12 Months Accounts and Financing Receivables [Table] Accounts and Financing Receivables [Table] Goodwill Goodwill Other Other Loans [Member] Other loans. Other comprehensive income (loss), net of tax and reclassification adjustments: Other Comprehensive Income (Loss), Net of Tax [Abstract] Residential Real Estate Residential Portfolio Segment [Member] Employee Stock Option Share-Based Payment Arrangement, Option [Member] Financing Receivable Portfolio Segment Financing Receivable Portfolio Segment [Axis] Debt Securities, Available-for-Sale [Table] Debt Securities, Available-for-Sale [Table] Other, net Proceeds from (Payments for) Other Financing Activities Total comprehensive income Total comprehensive income Comprehensive Income (Loss), Net of Tax, Attributable to Parent Pension Benefits Pension Plan [Member] Variable interest entities and asset securitizations Variable Interest Entities And Asset Securitizations [Text Block] Variable interest entities and asset securitizations. Award Type Award Type [Axis] Total debt securities Amortized cost Investment In Debt Securities Amortized Cost Investment in debt securities amortized cost. Premises and equipment Property, Plant and Equipment, Net Total liabilities Liabilities Common stock par value (in USD per share) Common Stock, Par or Stated Value Per Share HTM, less than 12 months, fair value Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value Revolving Loans Revolving Credit Facility [Member] Expiration Date Trading Arrangement Expiration Date Cash flows from investing activities Net Cash Provided by (Used in) Investing Activities [Abstract] Other revenues from operations Noninterest Income, Other Operating Income Brokerage services income Brokerage Services Income [Member] Brokerage Services Income Total Shareholder Return Amount Total Shareholder Return Amount Due after ten years Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year 10 Cash and due from banks Cash and Due from Banks Equity Awards Adjustments, Footnote Equity Awards Adjustments, Footnote [Text Block] Financial Asset, Aging [Domain] Financial Asset, Aging [Domain] Savings and interest-checking deposits Savings And Interest Checking Deposits Amount of domestic interest-bearing checking and savings accounts, which may include money market accounts, NOW accounts, interest-bearing corporate checking accounts, brokered deposits and other savings accounts. Due after one year through five years Debt Securities, Held-to-Maturity, Fair Value, Maturity, Allocated and Single Maturity Date, after Year One Through Five Other assets Other Assets, Fair Value Disclosure Debt Instrument [Line Items] Debt Instrument [Line Items] Named Executive Officers, Footnote Named Executive Officers, Footnote [Text Block] Internal Credit Assessment Internal Credit Assessment [Domain] Amortization of capitalized servicing rights Amortization of Mortgage Servicing Rights (MSRs) Basis of Accounting Basis of Accounting, Policy [Policy Text Block] Pledged financial instruments Financing Receivable, after Allowance for Credit Loss Net unrealized gains (losses) on investment securities OCI, Debt Securities, Available-for-Sale, Gain (Loss), after Adjustment and Tax Average common shares outstanding, diluted (in shares) Adjusted weighted-average shares outstanding (in shares) Weighted Average Number of Shares Outstanding, Diluted MNPI Disclosure Timed for Compensation Value MNPI Disclosure Timed for Compensation Value [Flag] AOCI Attributable to Parent, Net of Tax [Roll Forward] AOCI Attributable to Parent, Net of Tax [Roll Forward] Net income available to common shareholders Income available to common shareholders: Net Income (Loss) Available to Common Stockholders, Basic [Abstract] Total shareholders’ equity Beginning balance Ending balance Equity, Attributable to Parent Treasury stock — common, at cost — 16,894,734 shares at March 31, 2025; 13,922,820 shares at December 31, 2024 Treasury Stock, Value Due in one year or less Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, Year One Commitments to sell real estate loans Commitments To Sell Real Estate Loans [Member] Commitments to sell real estate loans. Year one Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year Revenues from sub-servicing Revenues From Subservicing Revenues from sub-servicing Mortgage-backed securities Debt Securities, Available-for-Sale, Maturity, without Single Maturity Date, Amortized Cost Standby letters of credit Letters of Credit Outstanding, Amount Trading account and other non-hedging derivative gains Trading Gain (Loss) Interest Payments On Variable Rate Commercial Real Estate Loans Interest Payments On Variable Rate Commercial Real Estate Loans [Member] Interest payments on variable rate commercial real estate loans. Total investment securities, 12 months or longer, fair value Investment Securities Continuous Unrealized Loss Position Twelve Months Or Longer Fair Value This item represents the fair value of securities that have been in a continuous loss position for twelve months or longer. Document Fiscal Period Focus Document Fiscal Period Focus Preferred Series G Series G Preferred Stock [Member] All Executive Categories All Executive Categories [Member] Plus: Incremental shares from assumed conversion of stock-based compensation awards Incremental Common Shares Attributable to Dilutive Effect of Share-Based Payment Arrangements Balance Sheet Location Statement of Financial Position Location, Balance [Domain] Investment Securities AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-Sale, Parent [Member] Changed Peer Group, Footnote Changed Peer Group, Footnote [Text Block] Assets Assets [Abstract] Retirement Plan Type Retirement Plan Type [Domain] Net charge-offs Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff (Recovery) Total other comprehensive income (loss) Net loss during period Other Comprehensive Income (Loss), Net of Tax Document Type Document Type Derivative Contract Derivative Contract [Domain] Loans Insured or Guaranteed by Government Authorities [Axis] Loans Insured or Guaranteed by Government Authorities [Axis] Information about Company's Segments Schedule of Segment Reporting Information, by Segment [Table Text Block] Junior subordinated debentures — M&T (a) Junior Subordinated Notes Fixed Derivative, Average Fixed Interest Rate Debt securities held to maturity: Debt Securities, Held-to-Maturity, Amortized Cost, after Allowance for Credit Loss, Maturity [Abstract] Commitments to originate real estate loans for sale Mortgage Related Commitments To Originate Real Estate Loans For Sale [Member] Mortgage related commitments to originate real estate loans for sale. Schedule Of Defined Benefit Plans Disclosures [Table] Defined Benefit Plan [Table] Revolving Loans Converted to Term Loans Revolving Loans Converted To Term Loans [Member] Revolving loans converted to term loans. Syndicated Loan Facility Syndicated Loan Facility [Member] Syndicated loan facility. Investment securities, available for sale, amortized cost Investment securities available for sale, amortized cost Debt Securities, Available-for-Sale, Amortized Cost Maximum Maximum [Member] Equity Valuation Assumption Difference, Footnote Equity Valuation Assumption Difference, Footnote [Text Block] Core deposit and other intangible assets Finite-Lived Intangible Assets, Net Investment Type Investment Type [Axis] Statistical Measurement Statistical Measurement [Axis] Non-Rule 10b5-1 Arrangement Terminated Non-Rule 10b5-1 Arrangement Terminated [Flag] Income before taxes Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Reduction in estimated fair value of interest rate contracts in asset position Increase Decrease In Estimated Fair Value Of Interest Rate Contracts In Asset Position Increase (decrease) in estimated fair value of interest rate contracts in asset position. Non-PEO NEO Average Total Compensation Amount Non-PEO NEO Average Total Compensation Amount Name Outstanding Recovery, Individual Name Disaggregation Of Revenue [Line Items] Disaggregation of Revenue [Line Items] Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract] Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract] Net increase (decrease) in cash, cash equivalents and restricted cash Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Period Increase (Decrease), Excluding Exchange Rate Effect Maximum exposure to loss of investments in real estate partnerships Maximum Exposure To Loss Of Investments In Real Estate Partnerships Maximum exposure to loss of investments in real estate partnerships. Award Timing Predetermined Award Timing Predetermined [Flag] Dividends paid — common Payments of Ordinary Dividends, Common Stock Investment, Name Investment, Name [Axis] Earnings per share, diluted (in USD per share) Diluted earnings per common share (in USD per share) Earnings Per Share, Diluted Counterparty Name [Domain] Counterparty Name [Domain] Commercial Bank Commercial Banking [Member] Commercial banking segment. Restatement does not require Recovery Restatement Does Not Require Recovery [Text Block] Residential real estate loans to be sold Commitments To Extend Credit For Residential Real Estate Loans To Be Sold Commitments to extend credit for residential real estate loans to be sold. Retirement Benefits [Abstract] Retirement Benefits [Abstract] Preferred stock, shares issued (in shares) Preferred Stock, Shares Issued Statement of Financial Position [Abstract] Statement of Financial Position [Abstract] Income taxes Income tax expense (benefit) Income Tax Expense (Benefit) Interest cost on projected benefit obligation Defined Benefit Plan, Interest Cost Recreational finance Recreational Finance [Member] Recreational finance. Investment in partnership carrying amount Investments In Variable Interest Entity Carrying Amount The carrying amount of investments in variable interest entity. Notional Amount Derivative, Notional Amount Equity and other securities (cost: $986 at March 31, 2025; $1,007 at December 31, 2024) Equity And Other Securities Estimated Fair Value Equity and other securities estimated fair value. Revenue from contract with customer Revenue from Contract with Customer, Excluding Assessed Tax Financing Receivable Portfolio Segment Financing Receivable Portfolio Segment [Domain] Statement of Comprehensive Income [Abstract] Statement of Comprehensive Income [Abstract] Year two Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year, Writeoff Interest expense Interest Expense, Operating and Nonoperating [Abstract] Net cash used by investing activities Net Cash Provided by (Used in) Investing Activities All Adjustments to Compensation All Adjustments to Compensation [Member] Due after one year through five years Debt Securities, Held-to-Maturity, Amortized Cost, after Allowance for Credit Loss, Maturity, Allocated and Single Maturity Date, after Year One through Five Additional paid-in capital Additional Paid in Capital Derivative Instruments Gain Loss By Hedging Relationship By Income Statement Location By Derivative Instrument Risk [Table] Derivative Instruments, Gain (Loss) [Table] Accumulated Other Comprehensive Income (Loss) [Line Items] Accumulated Other Comprehensive Income (Loss) [Line Items] Commitments and Contingencies Disclosure [Abstract] Commitments and Contingencies Disclosure [Abstract] Legal Entity [Axis] Legal Entity [Axis] Reduction in estimated fair value of interest rate contracts in liability position Increase Decrease In Estimated Fair Value Of Interest Rate Contracts In Liability Position Increase (decrease) in estimated fair value of interest rate contracts in liability position. Due in one year or less Debt Securities, Held-to-Maturity, Amortized Cost, after Allowance for Credit Loss, Maturity, Allocated and Single Maturity Date, Year One Commitments to extend credit Commitments To Extend Credit [Abstract] Commitments to extend credit. Automobile Automobile Loan [Member] Trading account Debt Securities, Trading, and Equity Securities, FV-NI Period of satisfaction of contract with customer Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period Cash Flow Hedges Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent [Member] Long-Term Debt, Type [Domain] Long-Term Debt, Type [Domain] Entity Address, State or Province Entity Address, State or Province Readily marketable securities Gross unrealized gains Readily Marketable Securities At Fair Value Gross Unrealized Gains Readily marketable securities at fair value gross unrealized gains. Derivative Instruments and Hedging Activities Disclosure [Abstract] Derivative Instruments and Hedging Activities Disclosure [Abstract] Schedule of Equity Method Investments [Line Items] Schedule of Equity Method Investments [Line Items] Year four Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year Erroneous Compensation Analysis Erroneous Compensation Analysis [Text Block] Other Revenues From Operations Other Revenues From Operations [Member] Other revenues from operations. Defined Benefit Plan Disclosure [Line Items] Defined Benefit Plan Disclosure [Line Items] Financial Instruments Financial Instruments [Domain] Accounts, Notes, Loans and Financing Receivable [Line Items] Accounts, Notes, Loans and Financing Receivable [Line Items] Prior Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year, Writeoff Preferred Series E Series E Preferred Stock [Member] Pledging Purpose [Axis] Pledging Purpose [Axis] Other liabilities Other Liabilities, Fair Value Disclosure HTM, 12 months or longer, gross unrealized losses Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss Restatement Determination Date Restatement Determination Date Estimated Fair Value Estimate of Fair Value Measurement [Member] Aggregate fair value of derivative financial instruments in asset position Derivative Asset, Subject to Master Netting Arrangement, before Offset of Collateral Interest received during the period Proceeds from Interest Received Pay vs Performance Disclosure Pay vs Performance Disclosure [Table] Interest Rate Contracts Interest Rate Contract [Member] Maturity Period 2025 Maturity Period One [Member] Maturity Period One [Member]. Loans Insured or Guaranteed by Government Authorities [Domain] Loans Insured or Guaranteed by Government Authorities [Domain] Advertising and marketing Marketing and Advertising Expense Investment Securities in Continuous Unrealized Loss Position Investment Securities In Continuous Unrealized Loss Position [Table Text Block] Investment securities in continuous unrealized loss position. Erroneously Awarded Compensation Recovery Erroneously Awarded Compensation Recovery [Table] Derivative Instruments, Gain (Loss) [Line Items] Derivative Instruments, Gain (Loss) [Line Items] FHLBs Facility Federal Home Loan Bank Advances [Member] Service charges on deposit accounts Deposit Account [Member] Loans secured by residential real estate that were in the process of foreclosure Residential Mortgage Loans Secured By Residential Real Estate In Process Of Foreclosure Residential mortgage loans secured by residential real estate in process of foreclosure. Prior Service Credit Accumulated Defined Benefit Plans Adjustment, Net Prior Service Attributable to Parent [Member] Earnings per common share Earnings Per Share [Text Block] Preferred Series H Series H Preferred Stock [Member] Retail Bank Retail Banking [Member] Retail banking segment. Weighted-average discount rates for fair value estimations Weighted-average Discount Rates for Fair Value Estimations Weighted-average discount rates for fair value estimations. Equity, attributable to parent, beginning balance Equity, attributable to parent, ending balance Equity, Attributable to Parent, Before Tax Equity, Attributable to Parent, Before Tax Equity, Attributable to Parent, Before Tax Peer Group Issuers, Footnote Peer Group Issuers, Footnote [Text Block] Segments Segments [Domain] Other Other Debt Obligations [Member] Interest income Interest and Dividend Income, Operating [Abstract] PEO PEO [Member] Commercial real estate loans to be sold Commitments To Extend Credit For Commercial Real Estate Loans To Be Sold Commitments to extend credit for commercial real estate loans to be sold. Name Trading Arrangement, Individual Name 30-89 days past due Financial Asset, 30 to 89 Days Past Due [Member] Financial Asset, 30 to 89 Days Past Due Fair Values Derivatives Balance Sheet Location By Derivative Contract Type By Hedging Designation [Table] Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Other costs of operations Other Noninterest Expense Equity and other securities, cost Equity and other securities, cost Equity And Other Securities At Cost Equity and other securities at cost. Income from equity method investments Income (Loss) from Equity Method Investments Loans and leases Interest and Fee Income, Loans and Leases Awards Close in Time to MNPI Disclosures, Table Awards Close in Time to MNPI Disclosures [Table Text Block] Prior Year End Fair Value of Equity Awards Granted in Any Prior Year that Fail to Meet Applicable Vesting Conditions During Covered Year Prior Year End Fair Value of Equity Awards Granted in Any Prior Year that Fail to Meet Applicable Vesting Conditions During Covered Year [Member] Aggregate Erroneous Compensation Amount Aggregate Erroneous Compensation Amount Local Phone Number Local Phone Number Equity and other securities Payments To Acquire Equity And Other Securities Investments Payments to acquire equity and other securities investments. Aggregate Erroneous Compensation Not Yet Determined Aggregate Erroneous Compensation Not Yet Determined [Text Block] Schedule Of Equity Method Investments [Table] Equity Method Investment [Table] Provision for credit losses Financing Receivable, Excluding Accrued Interest, Credit Loss Expense (Reversal) Revolving Loans Converted to Term Loans Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan, Writeoff Year five Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year PEO Total Compensation Amount PEO Total Compensation Amount Interest Income Interest Income [Member] Schedule Of Borrowings [Table] Schedule Of Borrowings [Table] Schedule of borrowings. Senior notes Senior Notes Equipment and net occupancy Occupancy, Net Liability derivatives, fair value Derivative Liability, Subject to Master Netting Arrangement, before Offset Investment securities available for sale: Debt Securities, Available-for-Sale, Excluding Accrued Interest Cost method equity securities Equity Securities, FV-NI, Cost Income Statement Location Statement of Income Location, Balance [Axis] Total other comprehensive income (loss) Other Comprehensive Income (Loss), before Tax, Portion Attributable to Parent Net change in loans originated for sale Increase (Decrease) in Loan, Held-for-Sale Debt Disclosure [Abstract] Debt Disclosure [Abstract] Common Stock Common Stock [Member] Loan and Leases Considered Nonaccrual and Interest Income Recognized on Loans Loan And Leases Considered Nonaccrual And Interest Income Recognized On Loans [Table Text Block] Loan and leases considered nonaccrual and interest income recognized on loans. Forgone Recovery due to Expense of Enforcement, Amount Forgone Recovery due to Expense of Enforcement, Amount Net income available to common equity Net Income Loss Available To Common Stockholders Diluted Before Unvested Stock Based Compensation Awards Adjustment Net income loss available to common stockholders before unvested stock based compensation awards adjustment as used in the determination of diluted earnings per common share. Stock-based compensation transactions, net Share Based Compensation Expense Net The adjustment to common stock or additional paid in capital for the amount of recognized equity-based compensation during the period. Segment Reporting [Abstract] Segment Reporting [Abstract] Entity Central Index Key Entity Central Index Key Outstanding principal balances of mortgage servicing rights Mortgage Loans Of Privately Held Company Mortgage servicing rights of commercial mortgage loans with outstanding principal balances of privately held commercial mortgage company. Due in one year or less Debt Securities, Held-to-Maturity, Fair Value, Maturity, Allocated and Single Maturity Date, Year One Equity Method Investments and Joint Ventures [Abstract] Equity Method Investments and Joint Ventures [Abstract] Non-PEO NEO Average Compensation Actually Paid Amount Non-PEO NEO Average Compensation Actually Paid Amount Less: Income attributable to unvested stock-based compensation awards Income Attributable To Unvested Stock Based Compensation Awards Basic Income attributable to unvested stock based compensation awards. This amount is used as a reduction to net income available to common equity in the calculation of net income available to common shareholders as used in the determination of basic earnings per common share. Shareholders' Equity Equity [Text Block] Award Timing, How MNPI Considered Award Timing, How MNPI Considered [Text Block] Financial Instrument Financial Instrument [Axis] Capital expenditures, net Payments for (Proceeds from) Productive Assets Segment information Segment Reporting Disclosure [Text Block] Fair Value Measurements Fair Value, Inputs, Level 1, Level 2, and Level 3 [Member] Net (increase) decrease in loan servicing advances Net Increase Decrease In Loan Servicing Advances The net cash outflow or inflow for the increase (decrease) of loan servicing advances. Actuarial Gains Accumulated Defined Benefit Plans Adjustment, Net Gain (Loss) Attributable to Parent [Member] Professional and other services Professional Fees Measurement Basis [Axis] Measurement Basis [Axis] Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Loans measured at fair value on nonrecurring basis Loans Receivable, Fair Value Disclosure Title Trading Arrangement, Individual Title Consolidated Entities Consolidated Entities [Axis] City Area Code City Area Code Unfunded Loan Commitment Unfunded Loan Commitment [Member] Number of debt securities with aggregate gross unrealized losses Number Of Debt Securities With Gross Losses Number of debt securities with gross losses. Insider Trading Policies and Procedures Not Adopted Insider Trading Policies and Procedures Not Adopted [Text Block] Preferred Stock Preferred Stock [Member] Total Charge-offs Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff Purchases of treasury stock Payments for Repurchase of Common Stock Document Information [Line Items] Document Information [Line Items] Schedule Of Segment Reporting Information By Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Net income per common share Earnings Per Share [Abstract] Equity [Abstract] Equity [Abstract] Debt securities available for sale: Debt Securities, Available-for-Sale, Fair Value, Fiscal Year Maturity [Abstract] Retained earnings Retained Earnings (Accumulated Deficit) Mortgage-backed securities Debt Securities, Held-to-Maturity, Maturity, without Single Maturity Date, Fair Value Class of Stock Class of Stock [Domain] Schedule of Borrowings Schedule of Debt [Table Text Block] Deferred income taxes and credits Deferred Income Taxes and Tax Credits Variable Derivative, Average Variable Interest Rate Summary of Loan grades applied various classes of Commercial and Real Estate Loans Summary Of Loan Grades Applied Various Classes Of Commercial And Real Estate Loans [Table Text Block] Summary of loan grades applied various classes of commercial and real estate loans. Aggregate Available Trading Arrangement, Securities Aggregate Available Amount Equity Awards Adjustments Equity Awards Adjustments [Member] Underlying Securities Award Underlying Securities Amount Investment securities Investments in Debt and Marketable Equity Securities (and Certain Trading Assets) Disclosure [Text Block] Beginning balance Ending balance Equity, Attributable To Parent, Tax Equity, Attributable To Parent, Tax Common stock cash dividends Dividends, Common Stock, Cash Net change in trading account and other non-hedging derivative assets and liabilities Increase (Decrease) in Financial Instruments Used in Operating Activities Amendment Flag Amendment Flag Carrying Amount Reported Value Measurement [Member] Stock Appreciation Rights (SARs) Stock Appreciation Rights (SARs) [Member] Modified past due 90 days or more Delinquency Status of Loans and Leases Receivable Modified Past Due Ninety Days or More Delinquency status of loans and leases receivable modified past due ninety days or more. Other commercial construction Other Commercial Construction [Member] Other commercial construction. Recoveries Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Recovery Due in one year or less Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, Year One Borrowings Debt Disclosure [Text Block] Fair Value Hierarchy and NAV Fair Value Hierarchy and NAV [Domain] Common shares outstanding (including common stock issuable) and unvested stock-based compensation awards Common shares outstanding (including common stock issuable) and unvested stock-based compensation awards Common Shares Outstanding Including Common Stock Issuable And Unvested Stock Based Compensation Awards The weighted average number of common shares outstanding (including common stock issuable) and unvested stock-based compensation awards. Financing receivable, accrued interest, before allowance for credit loss Financing Receivable, Accrued Interest, before Allowance for Credit Loss Bayview Financial Bayview Financial [Member] Bayview Financial. Recovery of Erroneously Awarded Compensation Disclosure [Line Items] Entity Address, Postal Zip Code Entity Address, Postal Zip Code Interest rate swap agreements Interest Rate Swap [Member] Other Projects Other Projects [Member] Other Projects Derivatives in fair value hedging relationships, hedged item Gain Loss On Hedged Item In Fair Value Hedge Aggregate net gain and losses (whether realized or unrealized) of the hedged item in a fair value hedge recognized in the income statement. Cash and cash equivalents Cash and Cash Equivalents, at Carrying Value FDIC assessments Federal Deposit Insurance Corporation Premium Expense Other, net Payments for (Proceeds from) Other Investing Activities Year-over-Year Change in Fair Value of Equity Awards Granted in Prior Years That are Outstanding and Unvested Year-over-Year Change in Fair Value of Equity Awards Granted in Prior Years That are Outstanding and Unvested [Member] Investments amortized to income tax expense Investment Program, Proportional Amortization Method, Applied, Amortization Expense Reclassification from AOCI, current period, tax Reclassification from AOCI, Current Period, Tax Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested [Member] Trading Activity, by Type Trading Activity, by Type [Domain] Fair Value Measurement Fair Value Measurement [Domain] Measurement Input, Commitment Expiration Measurement Input, Commitment Expiration [Member] Measurement Input, Commitment Expiration Adjustment To PEO Compensation, Footnote Adjustment To PEO Compensation, Footnote [Text Block] Class of Financing Receivable [Axis] Class of Financing Receivable [Axis] Credit cards Commitments To Extend Credit For Credit Cards Commitments To Extend Credit For Credit Cards Designated as Hedging Instrument Designated as Hedging Instrument [Member] Net income available to common stockholders, basic Net income available to common shareholders Net Income (Loss) Available to Common Stockholders, Basic Compensation Actually Paid vs. Other Measure Compensation Actually Paid vs. Other Measure [Text Block] Schedule of Stock by Class [Table] Stock, Class of Stock [Table] Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year [Member] Average common shares outstanding Adjusted weighted-average shares outstanding: Weighted Average Number of Shares Outstanding, Diluted [Abstract] Total assets Total assets of partnerships in which the company invested Assets SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate, Loan Type [Axis] SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate, Loan Type [Axis] Amortized Cost and Estimated Fair Value of Debt Securities by Contractual Maturity Amortized Cost And Estimated Fair Value Of Debt Securities By Contractual Maturity [Table Text Block] Amortized cost and estimated fair value of debt securities by contractual maturity. Forgone Recovery due to Violation of Home Country Law, Amount Forgone Recovery due to Violation of Home Country Law, Amount Termination Date Trading Arrangement Termination Date Preferred stock. dividend rate spread (as a percent) Preferred Stock, Dividend Rate Spread, Percent Preferred Stock, Dividend Rate Spread, Percent Equity securities, Gross Unrealized Losses Equity Securities Gross Unrealized Losses Equity securities gross unrealized losses. Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Financing Receivable, Impaired [Line Items] Financing Receivable, Impaired [Line Items] Common Stock Issuable Common Stock Issuable [Member] Common stock issuable. Loans And Leases Receivable [Table] Loans And Leases Receivable [Table] Loans and Leases receivable. Accrued interest and other liabilities Other Liabilities Investment securities: Marketable Securities [Abstract] Not Designated as Hedging Instrument Not Designated as Hedging Instrument [Member] SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate, Loan Type [Domain] SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate, Loan Type [Domain] Due after one year through five years Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year One Through Five Debt Instrument [Axis] Debt Instrument [Axis] Net income Net income Net income (loss) Net Income (Loss) Attributable to Parent Trading Arrangement: Trading Arrangement [Axis] Carrying Amounts and Estimated Fair Value for Financial Instrument Assets (Liabilities) Fair Value, by Balance Sheet Grouping [Table Text Block] Year three Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year Pay vs Performance Disclosure, Table Pay vs Performance [Table Text Block] Guaranteed by Government-Related Entities Loans Insured or Guaranteed by US Government Authorities [Member] Gross unrealized gains for held to maturity Debt Securities, Held-to-Maturity, Accumulated Unrecognized Gain Available line of credit Line of Credit Facility, Current Borrowing Capacity Equity Awards Adjustments, Excluding Value Reported in Compensation Table Equity Awards Adjustments, Excluding Value Reported in the Compensation Table [Member] Due after ten years Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, after Year 10 Summary of Current, Past Due and Nonaccrual Loans Loans And Leases Receivable Net Of Deferred Income By Accrual Status [Table Text Block] Loans and leases receivable net of deferred income by accrual status. Entity File Number Entity File Number Exempt from federal taxes Interest Income, Securities, Operating, Tax Exempt Consolidated Entities Consolidated Entities [Domain] Income Statement [Abstract] Income Statement [Abstract] Entity Address, Address Line One Entity Address, Address Line One Other comprehensive income (loss) before reclassifications: OCI, before Reclassifications, before Tax, Attributable to Parent Weighted-average shares outstanding: Weighted Average Number of Shares Outstanding, Basic [Abstract] Name Forgone Recovery, Individual Name Award Timing MNPI Considered Award Timing MNPI Considered [Flag] Mortgage-backed securities Debt Securities, Available-for-Sale, Maturity, without Single Maturity Date, Fair Value Service charges on deposit accounts Fees and Commissions, Depositor Accounts1 Fees and Commissions, Depositor Accounts1 Net change in accrued interest receivable, payable Net Change In Accrued Interest Receivable Payable Net change in accrued interest receivable, payable. Outstanding Aggregate Erroneous Compensation Amount Outstanding Aggregate Erroneous Compensation Amount Schedule of Preferred Stock Schedule of Stock by Class [Table Text Block] Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] PEO Actually Paid Compensation Amount PEO Actually Paid Compensation Amount Adjustment to Compensation: Adjustment to Compensation [Axis] Document Quarterly Report Document Quarterly Report Financial liabilities: Financial Instruments, Financial Liabilities, Balance Sheet Groupings [Abstract] Consumer: Consumer Portfolio Segment [Member] Due after one year through five years Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, after Year One Through Five Total interest expense Interest Expense, Operating Accumulated other comprehensive income (loss), net Accumulated Other Comprehensive Income (Loss), Net of Tax Pension Adjustments Service Cost Pension Adjustments Service Cost [Member] Average common shares outstanding, basic (in shares) Weighted-average shares outstanding (in shares) Weighted Average Number of Shares Outstanding, Basic Stock Price or TSR Estimation Method Stock Price or TSR Estimation Method [Text Block] AFS, 12 months or longer, gross unrealized losses Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss Document Information [Table] Document Information [Table] Trust income Noninterest Income, Trust Income Noninterest Income, Trust Income Capitalized servicing rights, valuation allowance Servicing Asset at Amortized Cost, Increase (Decrease) for Valuation Allowance Adjustment Average Maturity (in years) Derivative, Average Remaining Maturity Name Awards Close in Time to MNPI Disclosures, Individual Name FRB of New York FRB of New York [Member] FRB of New York. AFS, less than 12 months, gross unrealized losses Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss Entity Filer Category Entity Filer Category Amount of initial margin posted Collateral Already Posted, Aggregate Fair Value Uncollected amounts receivable Revenue, Remaining Performance Obligation, Amount Loss Contingencies [Line Items] Loss Contingencies [Line Items] Equity and other securities Proceeds From Sale Of Equity And Other Securities Investments Proceeds from sale of equity and other securities investments. Noninterest-bearing deposits Noninterest-Bearing Deposit Liabilities, Domestic Statistical Measurement Statistical Measurement [Domain] Investment securities available for sale, gross unrealized losses Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Loss, before Tax Other Commitments To Extend Credit For Commercial And Other Commitments to extend credit for commercial and other. Year four Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year, Writeoff Amount of foreclosed residential real estate property held Other Real Estate, Foreclosed Assets, and Repossessed Assets Derivatives, Fair Value [Line Items] Derivatives, Fair Value [Line Items] Debt Securities Debt Securities [Member] Summary of Payment Status of Loans Modified Financing Receivable, Past Due [Table Text Block] Loan Restructuring Modification Loan Restructuring Modification [Axis] Internal Credit Assessment Internal Credit Assessment [Axis] Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Commercial letters of credit Commitments Regarding Commercial Letters Of Credit Commitments regarding commercial letters of credit. All Trading Arrangements All Trading Arrangements [Member] Other direct expenses Other Direct Expenses Other Direct Expenses Compensation Actually Paid vs. Net Income Compensation Actually Paid vs. Net Income [Text Block] Variable Interest Entity Primary Beneficiary Variable Interest Entity, Primary Beneficiary [Member] Rule 10b5-1 Arrangement Adopted Rule 10b5-1 Arrangement Adopted [Flag] Long-term Debt Long-Term Debt [Member] Awards Close in Time to MNPI Disclosures Awards Close in Time to MNPI Disclosures [Table] Derivative [Line Items] Derivative [Line Items] Income taxes paid during the period Income Taxes Paid, Net Equity method investments Equity Method Investments Pay vs Performance Disclosure [Line Items] Less: Unvested stock-based compensation awards Unvested Stock Based Compensation Awards Number of shares related to unvested stock-based compensation awards. This amount is a reduction in the calculation of weighted average shares outstanding for the earnings per share calculation. Peer Group Total Shareholder Return Amount Peer Group Total Shareholder Return Amount Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis] Residential Residential Residential Mortgage-Backed Securities [Member] Derivative [Table] Derivative [Table] Information about Fair Values of Derivative Instruments in Consolidated Balance Sheet Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Table Text Block] Forward-Starting Interest Rate Swap Agreements Forward Starting Interest Rate Swap Agreements [Member] Forward starting interest rate swap agreements. Net change in other accrued income and expense Increase (Decrease) in Other Operating Assets and Liabilities, Net Other Performance Measure, Amount Other Performance Measure, Amount Defined Benefit Plan, Net Periodic Benefit Cost (Credit) Excluding Service Cost, Statement of Income or Comprehensive Income [Extensible Enumeration] Defined Benefit Plan, Net Periodic Benefit Cost (Credit) Excluding Service Cost, Statement of Income or Comprehensive Income [Extensible Enumeration] Pass Pass [Member] Cash flow hedges: Cash Flow Hedging [Member] Other Product and Service, Other [Member] Service cost Defined Benefit Plan, Service Cost Preferred stock, liquidation preference per share (in USD per share) Preferred Stock, Liquidation Preference Per Share Entity Tax Identification Number Entity Tax Identification Number Other Postretirement Benefits [Member] Retirement Plan Type [Axis] Loans and leases and the allowance for credit losses Loans, Notes, Trade and Other Receivables Disclosure [Text Block] Held-for-sale measurement input (as a percent) Loan, Held-for-Sale, Measurement Input Commitments and Contingent Liabilities Outstanding Commitments [Table Text Block] The tabular disclosure of commitments. Commitments to extend credit to commercial customers Commitments To Extend Credit To Commercial Customers Commitments to extend credit to commercial customers. Treasury Stock Treasury Stock, Common [Member] Equity Components Equity Components [Axis] Equity securities, Gross Unrealized Gains Equity Securities Gross Unrealized Gains Equity securities gross unrealized gains. Held to maturity (fair value: $12,308 at March 31, 2025; $12,955 at December 31, 2024) Amortized cost for held to maturity Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss Available for sale (cost: $20,807 at March 31, 2025; $19,054 at December 31, 2024) Investment securities available for sale, estimated fair value Debt Securities, Available-for-Sale Discount rates for fair value estimations Measurement Input Adjustments Measurement input adjustments. Investments Investments [Domain] Computations of Basic Earnings Per Common Share Schedule of Earnings Per Share, Basic, by Common Class, Including Two Class Method [Table Text Block] Supplemental schedule of noncash investing and financing activities Cash Flow, Noncash Investing and Financing Activities Disclosure [Abstract] Financing Receivable, Credit Quality Indicator [Line Items] Financing Receivable, Credit Quality Indicator [Line Items] Available for sale Proceeds from Maturities, Prepayments and Calls of Debt Securities, Available-for-Sale Modified past due 30-89 days Delinquency Status of Loans and Leases Receivable Modified Past Due Thirty to Eighty Nine Days Delinquency status of loans and leases receivable modified past due thirty to eighty nine days. Residential Mortgage Loans Residential Mortgage [Member] Aggregate Grant Date Fair Value of Equity Award Amounts Reported in Summary Compensation Table Aggregate Grant Date Fair Value of Equity Award Amounts Reported in Summary Compensation Table [Member] Loss contingency accrual Loss Contingency Accrual Debt Securities, Available-for-Sale [Line Items] Debt Securities, Available-for-Sale [Line Items] Advances from FHLB Federal Home Loan Bank, Advance, Maturity, Year One Cash, cash equivalents and restricted cash at beginning of period Cash, cash equivalents and restricted cash at end of period Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents Loans and leases average rate Debt, Weighted Average Interest Rate Revolving Loans Financing Receivable, Excluding Accrued Interest, Revolving, Writeoff Equity securities Equity Securities, FV-NI, Current Renewable Energy Renewable Energy [Member] Renewable Energy Total debt securities Estimated fair value Investment In Debt Securities Estimated Fair Value Investment in debt securities estimated fair value. Schedule of Held-to-Maturity Securities [Line Items] Schedule of Held-to-Maturity Securities [Line Items] Intersegment Activity Eliminated in Consolidated Totals Consolidation Items [Axis] Treasury stock (in shares) Treasury Stock, Common, Shares Forgone Recovery due to Disqualification of Tax Benefits, Amount Forgone Recovery due to Disqualification of Tax Benefits, Amount Interest Income Recognized Impaired Financing Receivable Nonaccrual Interest Income Impaired financing receivable nonaccrual interest income. Product and Service Product and Service [Domain] Fair Value Disclosures [Abstract] Fair Value Disclosures [Abstract] Trust income Fiduciary and Trust [Member] Due after five years through ten years Debt Securities, Held-to-Maturity, Fair Value, Maturity, Allocated and Single Maturity Date, after Year 5 Through 10 Net increase (decrease) in short-term borrowings Net Increase Decrease In Short Term Borrowings Net increase (decrease) in short term borrowings. Preferred stock, shares outstanding (in shares) Preferred Stock, Shares Outstanding Security Exchange Name Security Exchange Name Schedule Of Financing Receivable Recorded Investment Credit Quality Indicator [Table] Financing Receivable, Credit Quality Indicator [Table] Commercial and industrial Commitments To Extend Credit For Commercial And Industrial Commitments To Extend Credit For Commercial And Industrial Commercial Real Estate Commercial Real Estate Portfolio Segment [Member] Salaries and employee benefits Labor and Related Expense HTM, Less than 12 months, gross unrealized losses Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss Debt Securities, Available-for-Sale, Unrealized Loss Position, Accumulated Loss [Abstract] Debt Securities, Available-for-Sale, Unrealized Loss Position, Accumulated Loss [Abstract] Short-term borrowings Total short-term borrowings Short-Term Debt Forgone Recovery, Explanation of Impracticability Forgone Recovery, Explanation of Impracticability [Text Block] Nonrecurring Fair Value, Nonrecurring [Member] Institutional Services and Wealth Management Institutional Services And Wealth Management [Member] Institutional Services And Wealth Management Common stock issued (in shares) Common Stock, Shares, Issued Entity [Domain] Entity [Domain] Financing Receivable, before Allowance for Credit Loss Financing Receivable, before Allowance for Credit Loss Year three Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year, Writeoff Insider Trading Policies and Procedures Adopted Insider Trading Policies and Procedures Adopted [Flag] Estimated fair value gain (loss) Increase (Decrease) in Fair Value of Interest Rate Fair Value Hedging Instruments Asset-backed notes (a) Secured Long-Term Debt, Noncurrent Savings and interest-checking deposits Interest Expenses Savings And Interest Checking Deposits Interest expenses savings and interest checking deposits. Common stock authorized (in shares) Common Stock, Shares Authorized Hedged Item Derivative Assets (Liabilities), at Fair Value, Net Time deposits Interest Expense, Time Deposits Long-Term Debt, Type [Axis] Long-Term Debt, Type [Axis] Combination of Modification Types Combination of Modification Types [Member] Combination of modification types. Amortization of net actuarial gain Defined Benefit Plan, Amortization of Gain (Loss) Other assets for its "investment" in the common securities recognized by the company of various trusts Other Assets For Its Investment In Common Securities Recognized By Company Of Various Trusts Other assets for its "investment" in the common securities recognized by the company of various trusts. Balance Sheet Location Statement of Financial Position Location, Balance [Axis] Hedging Designation Hedging Designation [Domain] Provision for deferred income taxes Deferred Income Tax Expense (Benefit) Cash flow hedge reclassification before tax Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax Defined contribution pension and retirement savings plans total expense Pension and Other Postretirement Benefits Cost (Reversal of Cost) Total investment securities, less than 12 months, fair value Investment Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value This item represents the fair value of securities that have been in a continuous loss position for less than twelve months. Other comprehensive income (loss), net of Tax, Portion attributable to parent Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent Recurring Fair Value, Recurring [Member] Subordinated notes Subordinated Debt AFS, 12 months or longer, fair value Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer Asset write-downs Asset Impairment Charges Maturity Period 2028 Maturity Period Four [Member] Maturity Period Four Long-term borrowings (a) Total long-term borrowings Loan facility carrying amount Long-Term Debt Pension Adjustments Prior Service Cost Pension Adjustments Prior Service Cost [Member] Fixed Rate Available For Sale Securities Fixed Rate Available For Sale Securities [Member] Fixed Rate Available For Sale Securities Home equity lines and loans Home Equity Lines And Loans [Member] Home equity lines and loans. Loans Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss Mortgage-backed securities Debt Securities, Held-to-Maturity, Amortized Cost, after Allowance for Credit Loss, Maturity, without Single Maturity Date Fair Value By Balance Sheet Grouping [Table] Fair Value, by Balance Sheet Grouping [Table] Summary of Investment Holdings [Table] Investment Holdings [Table] Total debt securities Gross unrealized gains Investment In Debt Securities Gross Unrealized Gains Investment in debt securities gross unrealized gains. Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss [Abstract] Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss [Abstract] Pension Benefits Adjustments, Footnote Pension Benefits Adjustments, Footnote [Text Block] Time deposits Time Deposits, Fair Value Disclosure Time Deposits, Fair Value Disclosure Total Shareholder Return Vs Peer Group Total Shareholder Return Vs Peer Group [Text Block] Mortgage banking revenues Noninterest Income, Mortgage Banking Noninterest Income, Mortgage Banking Long-term borrowings Interest Expense, Long-Term Debt M&T Bank Parent [Member] Amortization of core deposit and other intangible assets Amortization of Intangible Assets Contract with customer Contract with Customer, Liability Preferred Series J Series J Preferred Stock [Member] Series J Preferred Stock Other Consumer, Other [Member] Accounting Policies [Abstract] Accounting Policies [Abstract] Liabilities Liabilities [Abstract] Less: Preferred stock dividends Preferred Stock Dividends, Income Statement Impact HTM, 12 months or longer, fair value Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value Current Fiscal Year End Date Current Fiscal Year End Date PEO Name PEO Name Time deposits Time Deposits Total investment securities, less than 12 months, gross unrealized losses Investment Securities Continuous Unrealized Loss Position Less Than Twelve Months Aggregate Losses Amount of accumulated unrealized loss on investments in debt and equity securities that have been in a continuous loss position for less than twelve months. All Award Types Award Type [Domain] Loan Restructuring Modification Loan Restructuring Modification [Domain] Other comprehensive income (loss) before reclassifications, tax Other Comprehensive Income (Loss) before Reclassifications, Tax Compensation Actually Paid vs. Company Selected Measure Compensation Actually Paid vs. Company Selected Measure [Text Block] Collateral relating to net asset positions Derivative Asset, Fair Value of Collateral Non-PEO NEO Non-PEO NEO [Member] OCI, before reclassifications, net of tax, attributable to parent OCI, before Reclassifications, Net of Tax, Attributable to Parent Additional Paid-in Capital Additional Paid-in Capital [Member] Hedging Relationship Hedging Relationship [Axis] Pension plans and other postretirement benefits Retirement Benefits [Text Block] Class of Stock [Line Items] Class of Stock [Line Items] Preferred Series I Series I Preferred Stocks [Member] Series I preferred stocks Year five Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year, Writeoff Modified in period Financing Receivable, Excluding Accrued Interest, Modified in Period, Amount Class of Stock Class of Stock [Axis] Net Periodic Defined Benefit Cost for Defined Benefit Plans Schedule of Defined Benefit Plans Disclosures [Table Text Block] Name Measure Name Entity Interactive Data Current Entity Interactive Data Current Available for sale Proceeds from Sale of Debt Securities, Available-for-Sale Financial guarantees and indemnification contracts Commitments Regarding Financial Guarantees And Indemnification Contracts Commitments regarding financial guarantees and indemnification contracts. Assets and Liabilities Measured at Estimated Fair Value on Recurring Basis Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] Disaggregation Of Revenue [Table] Disaggregation of Revenue [Table] Bayview Lending Group Bayview Lending Group [Member] Bayview Lending Group. Defined Benefit Plans Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member] Accounts Receivable, Allowance for Credit Loss [Roll Forward] Accounts Receivable, Allowance for Credit Loss [Roll Forward] Supplemental disclosure of cash flow information Supplemental Cash Flow Information [Abstract] Total other income Noninterest income Noninterest Income Federal tax credits and other federal tax benefits recognized Investment Program, Proportional Amortization Method, Elected, Income Tax Credit and Other Income Tax Benefit, before Amortization Expense Net income available to common stockholders, diluted Net income available to common shareholders Net Income (Loss) Available to Common Stockholders, Diluted Bayview Lending Group and Bayview Financial Bayview Lending Group And Bayview Financial [Member] Bayview Lending Group and Bayview Financial. Nonaccrual Nonaccrual [Member] Nonaccrual Information about Fair Values of Derivative Instruments in Consolidated Statement of Income Derivative Instruments, Gain (Loss) [Table Text Block] Amortized Cost Total Financing Receivable, Excluding Accrued Interest, Nonaccrual Preferred stock dividend rate (as a percent) Preferred Stock, Dividend Rate, Percentage Other Other Long-Term Debt Third Party Investors Third Party Investors [Member] Third Party Investors Privately issued Mortgage-Backed Securities, Issued by Private Enterprises [Member] Total deposits Deposits Deposits Total liabilities and shareholders’ equity Liabilities and Equity Rule 10b5-1 Arrangement Terminated Rule 10b5-1 Arrangement Terminated [Flag] Fair Value Hierarchy and NAV Fair Value Hierarchy and NAV [Axis] Hedging Designation Hedging Designation [Axis] Derivative financial instruments Derivative Instruments and Hedging Activities Disclosure [Text Block] Additions to right-of-use assets under operating leases Right-of-Use Asset Obtained in Exchange for Operating Lease Liability Underlying Security Market Price Change Underlying Security Market Price Change, Percent Expected return on plan assets Defined Benefit Plan, Expected Return (Loss) on Plan Assets Measurement Input Type [Axis] Measurement Input Type [Axis] 4.874% Asset-Backed Notes 4.874% Asset-Backed Notes [Member] 4.874% Asset-Backed Notes Individual: Individual [Axis] Loss on securitization of assets Gain (Loss) on Securitization of Financial Assets Accumulated Other Comprehensive Income (Loss), Net AOCI Attributable to Parent AOCI Attributable to Parent [Member] Home equity lines of credit Commitments To Extend Credit For Home Equity Lines Of Credit Commitments to extend credit for home equity lines of credit. Product and Service Product and Service [Axis] Statement [Line Items] Statement [Line Items] Measurement Input Type [Domain] Measurement Input Type [Domain] Investment securities pledged to secure debt carrying value Carrying Value Of Investment Securities Pledged Carrying value of investment securities pledged. Impact of estimated fair value gain (losses) on hedging instruments Impact In Estimated Fair Value Gain Losses On Hedging Instruments Impact in estimated fair value gain (losses ) on hedging instruments. Compensation Actually Paid vs. Total Shareholder Return Compensation Actually Paid vs. Total Shareholder Return [Text Block] Residential Residential Real Estate Excluding Alt A [Member] Residential real estate excluding Alt-A. Investment securities in held-to-maturity portfolio securitized by Bayview Financial Debt Security, Mortgage-Backed, Held-to-Maturity, Fair Value Disclosure Unrealized losses on individual debt securities Debt Securities, Unrealized Gain (Loss) Range of reasonably possible losses Loss Contingency, Estimate of Possible Loss Advances from FHLB Long-Term Federal Home Loan Bank Advances Real estate loans held for sale Loan, Held-for-Sale, Fair Value Disclosure Minimum Minimum [Member] Net gain on sales of assets Gain (Loss) on Disposition of Assets for Financial Service Operations Loan Modification Activities to Borrowers Experiencing Financial Difficulty on Financing Receivables Modifications to borrowers experiencing financial difficulty on financing receivables [Table Text Block] Modifications to borrowers experiencing financial difficulty on financing receivables. Adoption Date Trading Arrangement Adoption Date Due after five years through ten years Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year 5 Through 10 Variable Interest Entity [Line Items] Variable Interest Entity [Line Items] Segments Segments [Axis] Change in Fair Value as of Vesting Date of Prior Year Equity Awards Vested in Covered Year Change in Fair Value as of Vesting Date of Prior Year Equity Awards Vested in Covered Year [Member] Derivative Instrument Derivative Instrument [Axis] Exercise Price Award Exercise Price Components of Other Comprehensive Income (Loss) and Amounts Reclassified from Accumulated Other Comprehensive Income (Loss) to Net Income Components Of Other Comprehensive Income Loss [Table Text Block] The tabular disclosure of components of other comprehensive income loss. Arrangement Duration Trading Arrangement Duration Asset Pledged as Collateral without Right Asset Pledged as Collateral without Right [Member] Net increase in interest-bearing deposits at banks Proceeds from (Payments for) in Interest-Bearing Deposits in Banks Change in fair value of nonrecurring fair value measured loans for charge-offs and impairment reserves Increase Decrease In Fair Value Of Nonrecurring Fair Value Measured Loans For Charge Offs And Impairment Reserves Increase (decrease) in fair value of nonrecurring fair value measured loans for charge offs and impairment reserve. Investment securities: Interest and Dividend Income, Securities, by Taxable Status [Abstract] Gross realized gains (loss) on sale of investment securities Debt and Equity Securities, Realized Gain (Loss) Summary of loans in Accrual and Nonaccrual Status Summary Of Loans In Accrual And Nonaccrual Status [Table Text Block] Summary of loans in accrual and nonaccrual status. Variable Interest Entity [Table] Variable Interest Entity [Table] Foreign exchange and other option and futures contracts Foreign Exchange And Other Option And Futures Contracts [Member] Foreign exchange and other option and futures contracts. Shareholders' equity Equity, Attributable to Parent [Abstract] Subsidiaries Subsidiaries [Member] AFS, less than 12 months, fair value Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months Fixed Rate Long-Term Borrowings Fixed Rate Long Term Borrowings [Member] Fixed rate long-term borrowings. Other income Noninterest Income [Abstract] Total investment securities Investment securities held to maturity Investments Material Terms of Trading Arrangement Material Terms of Trading Arrangement [Text Block] Other commercial real estate Commitments To Extend Credit For Other Commercial Real Estate Commitments to extend credit for other commercial real estate. Other Accumulated Other [Member] Accumulated other. All Individuals All Individuals [Member] Gross unrealized losses for held to maturity Debt Securities, Held-to-Maturity, Accumulated Unrecognized Loss Net loans and leases Net loans and leases Financing Receivable, Excluding Accrued Interest, after Allowance for Credit Loss Other Postretirement Benefits Other Postretirement Benefits Plan [Member] Merchant discount and credit card interchange fees Credit Card, Merchant Discount [Member] Statement of Stockholders' Equity [Abstract] Statement of Stockholders' Equity [Abstract] Debt Securities, Available For Sale Debt Securities, Available For Sale [Member] Debt Securities, Available For Sale Repurchase agreements Short-term borrowings Federal Funds Purchased and Securities Sold under Agreements to Repurchase Preferred stock per share dividend amount (in USD per share) Preferred Stock, Dividends Per Share, Declared Amortized Cost and Estimated Fair Value of Investment Securities Amortized Cost And Estimated Fair Value Of Investment Securities [Table Text Block] Amortized cost and estimated fair value of investment securities. Receivables [Abstract] Receivables [Abstract] Preferred stock cash dividends Dividends, Preferred Stock, Cash Investment securities available for sale, gross unrealized gains Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Gain, before Tax Outside data processing and software Information Technology and Data Processing Accrued interest and other assets Interest Receivable and Other Assets All Other Other Operating Segment [Member] Other Commitments [Domain] Other Commitments [Domain] Brokerage services income Brokerage Commissions Revenue Lender Name [Axis] Lender Name [Axis] Due after five years through ten years Debt Securities, Held-to-Maturity, Amortized Cost, after Allowance for Credit Loss, Maturity, Allocated and Single Maturity Date, after Year 5 through 10 Schedule Of Financing Receivable Troubled Debt Restructurings [Table] Financing Receivable, Modified [Table] Relationship with Bayview Lending Group LLC and Bayview Financial Holdings, L.P. Relationship With Other Entities [Text Block] Relationship with other entities. Amortized Cost without Allowance Financing Receivable, Excluding Accrued Interest, Nonaccrual, No Allowance Fully taxable Interest Income, Securities, Operating, Taxable Allowance for credit losses Debt Securities, Held-to-Maturity, Allowance for Credit Loss Weighted-average remaining term Loans and leases weighted-average remaining term Loans and leases weighted-average remaining term Unfunded commitments includes carrying amount of its investments Unfunded Commitments Includes Carrying Amount Of Its Investments Unfunded commitments includes carrying amount of its investments. Defined benefit plans liability adjustments Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax Computations of Diluted Earnings Per Common Share Schedule of Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Table Text Block] Commitments and contingencies Commitments and Contingencies Disclosure [Text Block] Measure: Measure [Axis] Preferred stock, shares authorized Preferred Stock, Shares Authorized Entity Emerging Growth Company Entity Emerging Growth Company Change in cash flow hedges derivative instruments, fair value net Change in Cash Flow Hedges Derivative Instruments At Fair Value Net Change in Cash Flow Hedges Derivative Instruments At Fair Value Net Common stock issuable (in shares) Common Stock Issuable Share Number of shares of common stock issuable in connection with deferred compensation plans. Total liabilities Liabilities, Fair Value Disclosure Non-GAAP Measure Description Non-GAAP Measure Description [Text Block] Preferred stock, par value Preferred Stock, Par or Stated Value Per Share Equity Component Equity Component [Domain] Net interest income after provision for credit losses Interest Income (Expense), after Provision for Loan Loss Total interest income Interest and Dividend Income, Operating M&T M And T [Member] M&T. Additional 402(v) Disclosure Additional 402(v) Disclosure [Text Block] Entity Shell Company Entity Shell Company Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Other securities, Estimated fair value Federal Home Loan Bank Stock and Federal Reserve Bank Stock Held to maturity Proceeds from Maturities, Prepayments and Calls of Held-to-Maturity Securities 30-89 Days Past Due Financial Asset, 30 to 59 Days Past Due [Member] Summary of Investment Holdings [Line Items] Summary of Investment Holdings [Line Items] Statement [Table] Statement [Table] Measurement Frequency Measurement Frequency [Domain] Significant accounting policies Significant Accounting Policies [Text Block] Counterparty Name [Axis] Counterparty Name [Axis] Schedule of Variable Interest Entities Schedule of Variable Interest Entities [Table Text Block] Consolidation Items Consolidation Items [Domain] Year one Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year, Writeoff Financing Receivable, Past Due [Line Items] Financing Receivable, Past Due [Line Items] Interest paid during the period Interest Paid, Excluding Capitalized Interest, Operating Activities Level 1 Fair Value, Inputs, Level 1 [Member] Other Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax Year two Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year Statement of Cash Flows [Abstract] Statement of Cash Flows [Abstract] Average total assets Assets, Average Outstanding Percent of Total Loan Class Financing Receivable, Excluding Accrued Interest, Modified in Period, to Total Financing Receivables, Percentage Cash and cash equivalents Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract] Schedule of Long-Term Debt Instruments [Table] Schedule of Long-Term Debt Instruments [Table] Readily marketable securities Gross unrealized losses Readily Marketable Securities At Fair Value Gross Unrealized Losses Readily marketable securities at fair value gross unrealized losses. Other Commitments [Axis] Other Commitments [Axis] Accumulated Other Comprehensive Income Loss [Table] Accumulated Other Comprehensive Income (Loss) [Table] Due after five years through ten years Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, after Year 5 Through 10 Due after ten years Debt Securities, Held-to-Maturity, Amortized Cost, after Allowance for Credit Loss, Maturity, Allocated and Single Maturity Date, after Year 10 Percentage loans in the process of foreclosure, serviced by other entities, classified as government guaranteed Percentage Of Loans In The Process Of Foreclosure Serviced By Other Entities Classified As Government Guaranteed Percentage of loans in the process of foreclosure, serviced by other entities, classified as government guaranteed. Organization, Consolidation and Presentation of Financial Statements [Abstract] Net cash provided by financing activities Net Cash Provided by (Used in) Financing Activities Deposits at banks Interest Income, Domestic Deposits Credit Facility Credit Facility [Axis] Pledging Purpose [Domain] Pledging Purpose [Domain] Entity Registrant Name Entity Registrant Name Commercial Commercial Commercial Mortgage-Backed Securities [Member] Adjustment to Non-PEO NEO Compensation Footnote Adjustment to Non-PEO NEO Compensation Footnote [Text Block] Depreciation and amortization of premises and equipment Depreciation and amortization Depreciation, Depletion and Amortization Fair Value as of Grant Date Award Grant Date Fair Value Net increase in deposits Increase (Decrease) in Deposits Other Other Interest and Dividend Income Maximum credit risk for recourse associated with loans sold under Federal National Mortgage Association Delegated Underwriting and Servicing program Maximum Credit Risk For Recourse Associated With Loans Sold Under Federal National Mortgage Association Delegated Underwriting And Servicing Program Maximum credit risk for recourse associated with loans sold under Federal National Mortgage Association Delegated Underwriting and Servicing program. Level 2 Fair Value, Inputs, Level 2 [Member] Summary of Sources of Noninterest Income that are Subject to Revenue Recognition Accounting Guidance Disaggregation of Revenue [Table Text Block] Restatement Determination Date: Restatement Determination Date [Axis] Title of 12(b) Security Title of 12(b) Security Common stock, $0.50 par, 250,000,000 shares authorized, 179,436,779 shares issued at March 31, 2025 and December 31, 2024 Common Stock, Value, Issued Readily marketable securities Amortized cost Readily Marketable Securities At Fair Value Amortized Cost Readily marketable securities at fair value amortized cost. Interest-bearing deposits at banks Interest-Bearing Deposits in Banks and Other Financial Institutions Clearinghouse Credit Facilities Clearinghouse Credit Facilities [Member] Clearinghouse credit facilities. Due after ten years Debt Securities, Held-to-Maturity, Fair Value, Maturity, Allocated and Single Maturity Date, after Year 10 Other (a) Contractual Interest Rate Reduction [Member] Total investment securities, 12 months or longer, gross unrealized losses Investment Securities Continuous Unrealized Loss Position Twelve Months Or Longer Aggregate Losses Amount of accumulated unrealized loss on investments in debt and equity securities that have been in a continuous loss position for twelve months or longer. Cash flows from financing activities Net Cash Provided by (Used in) Financing Activities [Abstract] Preferred stock Carrying Amount Preferred Stock, Value, Issued Short-term borrowings Debt, Current [Abstract] Schedule Of Borrowings [Line Items] Schedule Of Borrowings [Line Items] Schedule of borrowings. Earnings per share, basic (in USD per share) Basic earnings per common share (in USD per share) Earnings Per Share, Basic Commercial and industrial Commercial Financial Leasing [Member] Commercial financial leasing. Award Timing MNPI Disclosure Award Timing MNPI Disclosure [Text Block] Other securities, Amortized cost Other Investments and Securities, at Cost Affordable Housing Projects Affordable Housing Projects [Member] Affordable Housing Projects Maturity Period 2027 Maturity Period Three [Member] Maturity Period Three [Member]. Aggregate Pension Adjustments Service Cost Aggregate Pension Adjustments Service Cost [Member] Schedule Of Impaired Financing Receivable [Table] Schedule of Impaired Financing Receivable [Table] Criticized nonaccrual Criticized Nonaccrual [Member] Criticized nonaccrual. Short-term borrowings Interest Expense, Short-Term Borrowings Gain (loss) on bank investment securities Gains (losses) on equity securities Debt and Equity Securities, Gain (Loss) Outstanding principal balances of residential mortgage loans from Bayview Financial Sub Serviced Residential Mortgage Loans Of Privately Held Company Outstanding principal balance of sub-serviced residential real estate loans for a privately-held specialty mortgage finance company. U.S. Treasury US Treasury and Government [Member] Investment securities, held to maturity, fair value Estimated fair value for held to maturity Debt Securities, Held-to-Maturity, Fair Value Financing Receivable, Allowance for Credit Losses [Line Items] Financing Receivable, Allowance for Credit Loss [Line Items] Total revenue Revenues Total available for held to maturity (fair value) Debt Securities, Held-to-Maturity, Maturity, Allocated and Single Maturity Date, Fair Value Commitments to sell real estate loans Commitments To Sell Real Estate Loans Notional Amount Commitments to sell real estate loans notional amount. Unamortized loan cost (fee) and purchase premium (discount) Financing Receivable, Unamortized Loan Cost (Fee) and Purchase Premium (Discount) Dividends paid — preferred Payments of Ordinary Dividends, Preferred Stock and Preference Stock Entity Address, City or Town Entity Address, City or Town Proceeds from long-term borrowings Proceeds from Issuance of Long-Term Debt Allowance for credit losses Beginning balance Ending balance Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest Contingent commitments to provide additional capital contributions to partnerships Contingent Commitments to Provide Additional Capital Contributions to Partnerships Contingent Commitments to Provide Additional Capital Contributions to Partnerships Investments, Debt and Equity Securities [Abstract] Investments, Debt and Equity Securities [Abstract] Comprehensive income Comprehensive Income (Loss) Note [Text Block] Loss Contingencies [Table] Loss Contingencies [Table] Net (increase) decrease in loans and leases Payments for (Proceeds from) Loans and Leases Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Total Compensation for Covered Year Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Total Compensation for Covered Year [Member] Current Financial Asset, Not Past Due [Member] Schedule Of Financing Receivable Allowance For Credit Losses [Table] Financing Receivable, Allowance for Credit Loss [Table] Cash flow hedges adjustments Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax Commercial and industrial Commercial Portfolio Segment [Member] Revenue from contracts with customers Revenue from Contract with Customer [Text Block] Document Fiscal Year Focus Document Fiscal Year Focus Total available for sale (fair value) Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Fair Value Purchases of treasury stock Treasury Stock, Value, Acquired, Cost Method Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Taxable-equivalent adjustment Taxable Equivalent Adjustment Taxable equivalent adjustment. Total assets Assets, Fair Value Disclosure Total available for held to maturity (amortized cost) Held To Maturity Securities Debt Maturities With Single Maturity Date Net Carrying Amount Carrying amount of debt securities accounted for as held-to-maturity, net of adjustments including, but not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized, and fair value hedge accounting adjustments, that have single maturity date. Document Period End Date Document Period End Date Information about Interest Rate Swap Agreements Schedule of Interest Rate Derivatives [Table Text Block] Readily marketable securities Estimated fair value Readily Marketable Securities At Estimated Fair Value Readily marketable securities at estimated fair value. Common stock issuable, 9,490 shares at March 31, 2025; 11,642 shares at December 31, 2024 Common Stock Issuable The obligation to issue shares of company common stock in connection with deferred compensation plans. Trading account Trading Account Trading account. Amortized Cost with Allowance Financing Receivable, Excluding Accrued Interest, Nonaccrual, With Allowance Financing Receivable, Excluding Accrued Interest, Nonaccrual, With Allowance Line of Credit Facility, Lender [Domain] Line of Credit Facility, Lender [Domain] Insider Trading Arrangements [Line Items] Financing Receivable, Modifications other than Troubled Debt Restructuring [Line Items] Financing Receivable, Modifications other than Troubled Debt Restructuring [Line Items] Financing receivable, modifications other than troubled debt restructuring. Debt securities available for sale: Debt Securities, Available-for-Sale, Amortized Cost, Fiscal Year Maturity [Abstract] Trading Activity Trading Activity [Axis] Less: Income attributable to unvested stock-based compensation awards Income Attributable To Unvested Stock Based Compensation Awards Diluted Income attributable to unvested stock based compensation awards. This amount is used as a reduction to net income available to common equity in the calculation of net income available to common shareholders as used in the determination of diluted earnings per share. Document Transition Report Document Transition Report Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Table] Fair Value, Recurring and Nonrecurring [Table] Entity Current Reporting Status Entity Current Reporting Status Retained Earnings Retained Earnings [Member] Long-term borrowings Long-Term Debt, Excluding Current Maturities [Abstract] Accruing Loans Past Due 90 Days or More Financial Asset, Equal to or Greater than 90 Days Past Due [Member] Net income available to common equity Net Income Loss Available To Common Stockholders Basic Before Unvested Stock Based Compensation Awards Adjustment Net income loss available to common stockholders before unvested stock based compensation awards adjustment as used in the determination of basic earnings per common share. Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Total other expense Noninterest Expense Executive Category: Executive Category [Axis] Carrying value of investment securities pledged related to repurchase transactions Carrying Value of Investment Securities Pledged Related to Repurchase Transactions Carrying value of investment securities pledged related to repurchase transactions.. Reclassification from AOCI, current period, net of tax, attributable to parent Reclassification from AOCI, Current Period, Net of Tax, Attributable to Parent Income Statement Location Statement of Income Location, Balance [Domain] Available for sale Payments to Acquire Debt Securities, Available-for-Sale Company Selected Measure Name Company Selected Measure Name