The amount of residual value associated with financing leases that are guaranteed by the lessees or others.

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Loans and leases receivable.

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No definition available.

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Loans and leases weighted-average remaining term

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Percentage of loans in the process of foreclosure, serviced by other entities, classified as government guaranteed.

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No definition available.

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- Definition

Residential mortgage loans secured by residential real estate in process of foreclosure.

+ References

No definition available.

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- Definition

Amortized cost of financing receivable modified during period for debtor experiencing financial difficulty.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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For an unclassified balance sheet, reflects the carrying amount of unpaid loan amounts due from related parties at the balance sheet date.

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Reflects the amount of new advances made to related parties in the form of loan and lease receivables.

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Describes transactions with related parties, including directors, officers and key employees, including: (1) the aggregate amount of related party loans if they exceed 5 percent of shareholders' equity at the balance sheet date or at any time during the latest fiscal year, (2) an analysis of activity with respect to such loans for the latest fiscal year (i.e., beginning balance, new loans, repayments, other changes and ending balance), (3) the aggregate amount of any significant nonaccrual of interest, past due amounts, or restructured or potential problem (including additional information necessary to understand the impact on the financial statements), and (4) any related party loans not made in the ordinary course of business.

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Amount of cash inflow from related parties which reduce the amount of loans and leases receivable due from related parties.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Amount, after valuation allowance, of financing receivable held for sale and not part of disposal group. Excludes loan covered under loss sharing agreement and loan classified as investment in debt security.

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Amortized cost, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Carrying amount as of the balance sheet date of other real estate and foreclosed assets. Other real estate may include real estate investments, real estate loans that qualify as investments in real estate, and premises that are no longer used in operations may also be included in real estate owned. Foreclosed assets include all assets obtained in full or partial satisfaction of a debt arrangement through foreclosure proceedings.

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Loans and Leases - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Loans And Leases Receivable [Line Items]
Amount of foreclosed residential real estate property held	$ 39	$ 41
Loans secured by residential real estate that were in the process of foreclosure	$ 170	201
Percentage loans in the process of foreclosure, serviced by other entities, classified as government guaranteed	35.00%
Guaranteed amount included in the estimated residual value of leased assets associated with financing leases	$ 96	93
Financing Receivable, Troubled Debt Restructuring, Postmodification		280	$ 529
Remaining balance of loans and leases	$ 134,936	132,074
Residential Real Estate Loans [Member]
Loans And Leases Receivable [Line Items]
Weighted-average remaining term	10 years 7 months 6 days
Payment Deferral [Member]
Loans And Leases Receivable [Line Items]
Financing Receivable, Troubled Debt Restructuring, Postmodification		203	$ 247
Director and Certain Officers [Member]
Loans And Leases Receivable [Line Items]
Exclusion limit of loans from related party disclosure	less than $60,000
Borrowing by directors and certain officers of M&T and its banking subsidiaries and their associates	$ 116	102
New borrowings by directors, certain officers and their associates	49
Repayments and other reductions of borrowings by directors, certain officers and their associates	35
Residential Mortgage Loans [Member] \| Asset Pledged as Collateral without Right [Member] \| FHLBs Facility [Member]
Loans And Leases Receivable [Line Items]
Pledged financial instruments	18,800
Residential Mortgage Loans [Member] \| One-to-Four Family Residential [Member]
Loans And Leases Receivable [Line Items]
Mortgage loans held for sale	190	32
Commercial Real Estate Loans [Member] \| Asset Pledged as Collateral without Right [Member] \| FHLBs Facility [Member]
Loans And Leases Receivable [Line Items]
Pledged financial instruments	16,400
Commercial Real Estate Loans [Member] \| One-to-Four Family Residential [Member]
Loans And Leases Receivable [Line Items]
Mortgage loans held for sale	$ 189	$ 131
Commercial and Industrial [Member]
Loans And Leases Receivable [Line Items]
Weighted-average remaining term	1 year 3 months 18 days
Residential Builder and Developer [Member]
Loans And Leases Receivable [Line Items]
Weighted-average remaining term	1 year 1 month 6 days
Other Commercial Construction [Member]
Loans And Leases Receivable [Line Items]
Weighted-average remaining term	1 year 1 month 6 days
Commercial and Industrial Loans [Member] \| Asset Pledged as Collateral without Right [Member] \| FHLBs Facility [Member]
Loans And Leases Receivable [Line Items]
Pledged financial instruments	$ 13,400
Home Equity Loans and Lines of Credit [Member] \| Asset Pledged as Collateral without Right [Member] \| FHLBs Facility [Member]
Loans And Leases Receivable [Line Items]
Pledged financial instruments	2,600
Asset-Backed Securities [Member]
Loans And Leases Receivable [Line Items]
Remaining balance of loans and leases	599
Other Consumer Loans [Member] \| Asset Pledged as Collateral without Right [Member] \| FHLBs Facility [Member]
Loans And Leases Receivable [Line Items]
Pledged financial instruments	$ 11,000