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Regulatory Matters - Summary of Required Minimum and Well Capitalized Capital Ratios (Detail) | Dec. 31, 2024
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M&T (Consolidated) |
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |
CET1 to RWA, Minimum | 4.50%
Tier 1 capital to RWA, Minimum | 0.060
Total capital to RWA, Minimum | 0.080
Leverage - Tier 1 capital to average total assets, as defined | 0.040
Tier 1 capital to RWA, Well capitalized | 0.060
Total capital to RWA, Well capitalized | 0.100
Bank Subsidiaries |
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |
CET1 to RWA, Minimum | 4.50%
Tier 1 capital to RWA, Minimum | 0.060
Total capital to RWA, Minimum | 0.080
Leverage - Tier 1 capital to average total assets, as defined | 0.040
CET1 to RWA, Well Capitalized | 6.50%
Tier 1 capital to RWA, Well capitalized | 0.080
Total capital to RWA, Well capitalized | 0.100
Leverage - Tier 1 capital to average total assets, as defined | 0.050

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- Definition Ratio of minimum total risk-based capital to risk-weighted assets categorized as well capitalized as defined by regulatory framework for prompt corrective action. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 942 -SubTopic 505 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (c)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477270/942-505-50-1 + Details
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