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v3.25.4

Securities - Narrative (Details) | 12 Months Ended
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Dec. 31, 2025 USD ($) security | Dec. 31, 2024 USD ($) security | Dec. 31, 2023 USD ($)
Certain Loans Acquired in Transfer Accounted for as Debt Securities Accretable Yield Movement Schedule [Line Items] |  |  |
Number of available-for-sale debt securities in an unrealized loss position | security | 429 | 541 |
Debt securities, available-for-sale, allowance for credit loss | $ 1,900,000 | $ 0 |
Allowance for credit losses on available-for-sale debt securities | 1,900,000 | 0 | $ 0
Allowance for credit losses | 0 | 0 |
Asset Pledged as Collateral |  |  |
Certain Loans Acquired in Transfer Accounted for as Debt Securities Accretable Yield Movement Schedule [Line Items] |  |  |
AFS and HTM debt securities carrying value | 4,600,000,000 | $ 5,400,000,000 |
Prepositioned For Federal Reserve Bank Standing Repurchase Agreement Facility |  |  |
Certain Loans Acquired in Transfer Accounted for as Debt Securities Accretable Yield Movement Schedule [Line Items] |  |  |
AFS and HTM debt securities carrying value | $ 4,600,000,000 |  |
U.S. government agency and U.S. government-sponsored enterprise mortgage-backed securities |  |  |
Certain Loans Acquired in Transfer Accounted for as Debt Securities Accretable Yield Movement Schedule [Line Items] |  |  |
Number of available-for-sale debt securities in an unrealized loss position | security | 222 | 290 |
Corporate debt securities |  |  |
Certain Loans Acquired in Transfer Accounted for as Debt Securities Accretable Yield Movement Schedule [Line Items] |  |  |
Number of available-for-sale debt securities in an unrealized loss position | security | 47 | 66 |
Debt securities, available-for-sale, allowance for credit loss | $ 0 |  |
Non-agency mortgage-backed securities |  |  |
Certain Loans Acquired in Transfer Accounted for as Debt Securities Accretable Yield Movement Schedule [Line Items] |  |  |
Number of available-for-sale debt securities in an unrealized loss position | security | 66 | 83 |
Debt securities, available-for-sale, allowance for credit loss | $ 2,000,000 |  |
Allowance for credit losses on available-for-sale debt securities | $ 2,000,000 |  |

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