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Regulatory Matters - Additional Information (Detail) $ in Billions | Dec. 31, 2024 USD ($) | Oct. 01, 2024
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Regulatory Capital Requirements under Banking Regulations [Abstract] |  |
Funds available for payment of dividends to M&T from banking subsidiaries | $ 2.3 |
Capital conservation buffer | 2.50% |
Capital conservation buffer ratio effective |  | 0.038
CET1 capital requirement ratio | 8.30% |

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- Definition Capital Conservation Buffer Ratio + References No definition available. + Details
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- Definition Capital Conservation Buffer Ratio Effective + References No definition available. + Details
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- Definition Common Equity Tier One Capital Requirement Ratio + References No definition available. + Details
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- Definition Funds Available For Payment Of Dividends To Parent Company From Banking Subsidiaries + References No definition available. + Details
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