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

No definition available.

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- Definition

Loans and leases receivable.

+ References

No definition available.

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- Definition

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

+ References

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

Amount, after troubled debt restructuring, of modified financing receivable.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI https://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524

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- Definition

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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- Definition

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

+ References

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- Definition

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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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Topic 310
-SubTopic 10
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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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- Definition

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

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-Paragraph 1
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Loans and Leases - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Loans And Leases Receivable [Line Items]
Amount of foreclosed residential real estate property held	$ 41,000	$ 24,000
Loans secured by residential real estate that were in the process of foreclosure	$ 201,000	151,000
Percentage loans in the process of foreclosure, serviced by other entities, classified as government guaranteed	42.00%
Guaranteed amount included in the estimated residual value of leased assets associated with direct financing leases	$ 93,000	29,000
Financing Receivable, Troubled Debt Restructuring, Postmodification	279,832	529,323	$ 806,046
Payment Deferral [Member]
Loans And Leases Receivable [Line Items]
Financing Receivable, Troubled Debt Restructuring, Postmodification	202,866	246,598	$ 545,415
COVID-19 [Member] \| Government-Guaranteed Loans [Member]
Loans And Leases Receivable [Line Items]
Financing Receivable, Troubled Debt Restructuring, Postmodification	8,000	974,000
Residential Real Estate [Member] \| COVID-19 [Member] \| Payment Deferral [Member]
Loans And Leases Receivable [Line Items]
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 19,000	1,200,000
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	$ 102,000	113,000
New borrowings by directors, certain officers and their associates	7,000
Repayments and other reductions of borrowings by directors, certain officers and their associates	18,000
Commercial Real Estate [Member] \| Asset Pledged as Collateral without Right [Member] \| FHLBs Facility [Member]
Loans And Leases Receivable [Line Items]
Pledged financial instruments	16,300,000
Residential Mortgage Loans [Member] \| Asset Pledged as Collateral without Right [Member] \| FHLBs Facility [Member]
Loans And Leases Receivable [Line Items]
Pledged financial instruments	19,500,000
Residential Mortgage Loans [Member] \| One-to-Four Family Residential [Member]
Loans And Leases Receivable [Line Items]
Mortgage loans held for sale	32,000	474,000
Commercial Real Estate Loans [Member] \| One-to-Four Family Residential [Member]
Loans And Leases Receivable [Line Items]
Mortgage loans held for sale	131,000	$ 425,000
Commercial Loans and Leases [Member] \| Asset Pledged as Collateral without Right [Member] \| FHLBs Facility [Member]
Loans And Leases Receivable [Line Items]
Pledged financial instruments	10,500,000
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	2,400,000
Other Consumer Loans [Member] \| Asset Pledged as Collateral without Right [Member] \| FHLBs Facility [Member]
Loans And Leases Receivable [Line Items]
Pledged financial instruments	$ 10,700,000