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v3.25.1

Relationship with Bayview Lending Group LLC and Bayview Financial Holdings, L.P. - Additional Information (Detail) - USD ($) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2025 | Mar. 31, 2024 | Dec. 31, 2024
Schedule of Equity Method Investments [Line Items] |  |  |  |
Revenue from contract with customer |  | $ 397,000,000 | $ 367,000,000 |
Loan facility carrying amount | [1] | 10,496,000,000 |  | $ 12,605,000,000
Loans and leases (a) | [1] | 134,574,000,000 |  | 135,581,000,000
Deposits |  | 165,409,000,000 |  | 161,095,000,000
Bayview Financial |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |
Deposits |  | 3,200,000,000 |  | 2,200,000,000
Commercial and industrial |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |
Loans and leases (a) |  | $ 60,596,000,000 |  | 61,481,000,000
Bayview Lending Group |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |
Ownership percentage (as a percent) |  | 20.00% |  |
Equity method investments |  | $ 0 |  |
Bayview Lending Group | Other Revenues From Operations |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |
Income from equity method investments |  |  | 25,000,000 |
Bayview Lending Group and Bayview Financial |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |
Outstanding principal balances of mortgage servicing rights |  | 971,000,000 |  | 1,000,000,000.0
Revenue from contract with customer |  | 1,000,000 |  |
Bayview Financial |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |
Outstanding principal balances of residential mortgage loans from Bayview Financial |  | 161,000,000,000.0 |  | 111,500,000,000
Revenues from sub-servicing |  | 40,000,000 | $ 32,000,000 |
Investment securities in held-to-maturity portfolio securitized by Bayview Financial |  | 36,000,000 |  | $ 37,000,000
Bayview Financial | Commercial and industrial |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |
Loans and leases (a) |  | 306,000,000 |  |
Bayview Financial | Syndicated Loan Facility |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |
Loan facility carrying amount |  | 2,600,000,000 |  |
Bayview Financial | Syndicated Loan Facility | M&T Bank |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |
Loan facility carrying amount |  | $ 394,000,000 |  |
[1] | Loans and leases of $2.1 billion and $1.5 billion at March 31, 2025 and December 31, 2024, respectively, were held in special purpose trusts to settle the respective obligations of asset-backed notes issued by those trusts. The outstanding balances of those asset-backed notes were included in Long-term borrowings and were $1.8 billion at March 31, 2025 and $1.2 billion at December 31, 2024.

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