ACL For Non Purchased Credit Deteriorated Loan And Leases

No definition available.

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- Definition

Delinquency Status Of Loans And Leases Receivable Modified Past Due Ninety Days Or More

+ References

No definition available.

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- Definition

Delinquency Status Of Loans And Leases Receivable Modified Past Due Thirty To Eighty Nine Days

+ References

No definition available.

+ Details

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- Definition

Financing Receivable Recorded Investment Accrual Or Nonaccrual Status

+ References

No definition available.

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- Definition

Loan Delinquent Period For Nonaccrual Status Classification

+ References

No definition available.

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- Definition

LoansAndLeasesReceivableLineItems

+ References

No definition available.

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- Definition

Loans And Leases Weighted Average Remaining Term

+ References

No definition available.

+ Details

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- Definition

PercentageOfLoansInTheProcessOfForeclosureServicedByOtherEntitiesClassifiedAsGovernmentGuaranteed

+ References

No definition available.

+ Details

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- Definition

Residential Mortgage Loans Secured By Residential Real Estate In Process Of Foreclosure

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Amount of writeoff of financing receivable, charged against allowance for credit loss.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 11B
-Subparagraph (c)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-11B

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 326
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

Amortized cost excluding accrued interest, before allowance for credit loss, fee, and loan in process, of financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(7))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amortized cost excluding accrued interest, of financing receivable modified during period for debtor experiencing financial difficulty.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-42

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Period Type:	duration

- Definition

Amount of unamortized loan commitment, origination, and other costs (fees) and purchase premium (discount) on financing receivable recognized as adjustment to yield. Excludes financing receivable covered under loss sharing agreement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481598/310-20-45-1

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 3: http://www.xbrl.org/2003/role/recommendedDisclosureRef
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-Publisher FASB
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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

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

+ References

+ Details

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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/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 12
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-12

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Section S99
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-SubTopic 210
-Topic 942
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

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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

+ Details

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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/2009/role/commonPracticeRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
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-URI https://asc.fasb.org/1943274/2147481990/310-10-45-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1

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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.

+ References

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- Details

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- Details

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Loans and leases and allowance for credit losses - Additional Information (Detail) - USD ($) $ in Millions		12 Months Ended
	Apr. 01, 2022	Dec. 31, 2024	Dec. 31, 2023
Loans And Leases Receivable [Line Items]
Unamortized loan cost (fee) and purchase premium (discount)		$ 277	$ 361
ACL for non-PCD loan and leases	$ 242
Modified in period		1,130	1,586
Loans and leases		$ 135,581	134,068
Maximum
Loans And Leases Receivable [Line Items]
Loan delinquent period		150 days
Term Extension
Loans And Leases Receivable [Line Items]
Modified in period		$ 1,001	1,476
Director and Certain Officers
Loans And Leases Receivable [Line Items]
Borrowing by directors and certain officers of M&T and its banking subsidiaries and their associates		50	116
New borrowings by directors, certain officers and their associates		1
Repayments and other reductions of borrowings by directors, certain officers and their associates		66
Guaranteed by Government-Related Entities
Loans And Leases Receivable [Line Items]
Modified in period		143	124
30-89 Days Past Due		34	40
Past Due 90 Days or More		$ 36	24
Percentage loans in the process of foreclosure, serviced by other entities, classified as government guaranteed		37.00%
Unfunded Commitments to Extend Credit
Loans And Leases Receivable [Line Items]
Modified in period		$ 69	$ 128
Non PCD Acquired Loans
Loans And Leases Receivable [Line Items]
ACL for non-PCD loan and leases	242
PCD Acquired Loans
Loans And Leases Receivable [Line Items]
Allowance for credit loss, write-off	$ 33
Commercial Loans and Commercial Real Estate \| Minimum
Loans And Leases Receivable [Line Items]
Amount of real estate loan as reported as accruing or non-accruing		$ 5
Commercial Real Estate
Loans And Leases Receivable [Line Items]
Weighted-average remaining term		1 year	1 year 1 month 6 days
Commercial Real Estate \| Asset Pledged as Collateral without Right \| FHLBs Facility
Loans And Leases Receivable [Line Items]
Pledged financial instruments		$ 14,600
Commercial Real Estate \| Commercial
Loans And Leases Receivable [Line Items]
Mortgage loans held for sale		310	$ 189
Modified in period		515	651
Loans and leases		20,780	25,277
Commercial Real Estate \| Commercial \| Term Extension
Loans And Leases Receivable [Line Items]
Modified in period		$ 509	$ 610
Residential Real Estate
Loans And Leases Receivable [Line Items]
Weighted-average remaining term		10 years 4 months 24 days	10 years 7 months 6 days
Residential Real Estate \| Asset Pledged as Collateral without Right \| FHLBs Facility
Loans And Leases Receivable [Line Items]
Pledged financial instruments		$ 18,600
Residential Real Estate \| Residential Real Estate Loans
Loans And Leases Receivable [Line Items]
Amount of foreclosed residential real estate property held		35	$ 39
Loans secured by residential real estate that were in the process of foreclosure		173	170
Residential Real Estate \| Residential
Loans And Leases Receivable [Line Items]
Mortgage loans held for sale		211	190
Modified in period		177	177
Loans and leases		23,166	23,264
Residential Real Estate \| Residential \| Term Extension
Loans And Leases Receivable [Line Items]
Modified in period		146	148
Commercial Portfolio Segment
Loans And Leases Receivable [Line Items]
Modified in period		$ 303	$ 198
Weighted-average remaining term		10 months 24 days	1 year 3 months 18 days
Loans and leases		$ 61,481	$ 57,010
Commercial Portfolio Segment \| Term Extension
Loans And Leases Receivable [Line Items]
Modified in period		212	169
Commercial Portfolio Segment \| Asset Pledged as Collateral without Right \| FHLBs Facility
Loans And Leases Receivable [Line Items]
Pledged financial instruments		20,700
Consumer: \| Other
Loans And Leases Receivable [Line Items]
Modified in period		0	0
Loans and leases		2,220	2,092
Consumer: \| Other \| Term Extension
Loans And Leases Receivable [Line Items]
Modified in period		0	0
Consumer: \| Other \| Asset Pledged as Collateral without Right \| FHLBs Facility
Loans And Leases Receivable [Line Items]
Pledged financial instruments		13,100
Consumer: \| Home equity lines and loans
Loans And Leases Receivable [Line Items]
Modified in period		2	1
Loans and leases		4,592	4,649
Consumer: \| Home equity lines and loans \| Term Extension
Loans And Leases Receivable [Line Items]
Modified in period		1	0
Consumer: \| Home equity lines and loans \| Asset Pledged as Collateral without Right \| FHLBs Facility
Loans And Leases Receivable [Line Items]
Pledged financial instruments		2,700
Consumer: \| Automobile
Loans And Leases Receivable [Line Items]
Modified in period		0	0
Loans and leases		4,794	3,992
Consumer: \| Automobile \| Term Extension
Loans And Leases Receivable [Line Items]
Modified in period		0	$ 0
Consumer: \| Equipment Finance Loans And Leases
Loans And Leases Receivable [Line Items]
Loans and leases		$ 1,500