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Securities - Additional Information (Details) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 30, 2024 USD ($) shares | Dec. 31, 2024 USD ($) Security Segment | Dec. 31, 2023 USD ($) Security | Dec. 31, 2022 USD ($)
Schedule Of Held To Maturity Securities [Line Items] |  |  |  |
Number of Investment Securities Segments | Segment |  | 2 |  |
Credit losses |  | $ 0 |  |
Municipal securities percentage of securities portfolio |  | 0.90% |  |
Securities in Unrealized Loss Positions Qualitative Disclosure Number of Positions Greater Than or Equal to One Year | Security |  | 949 | 941 |
Gain (loss) on sale of investment securities |  | $ 9,400 | $ 0 | $ 0
Available for Sale Securities, Amortized Cost Basis |  | 339,016,000 | 440,358,000 |
Debt Securities, Available-for-Sale |  | 336,960,000 | 438,588,000 |
Collateralized Securities [Member] |  |  |  |
Schedule Of Held To Maturity Securities [Line Items] |  |  |  |
Available for Sale Securities, Amortized Cost Basis |  | 10,260,000,000 | 11,340,000,000 |
Debt Securities, Available-for-Sale |  | $ 8,910,000,000 | $ 10,090,000,000.00 |
Securities Concentration Risk [Member] | Stockholders' Equity, Total [Member] | Other Than U.S. Government and Agencies [Member] |  |  |  |
Schedule Of Held To Maturity Securities [Line Items] |  |  |  |
Concentration Risk, Percentage |  | 10.00% | 10.00% |
Visa Stock Exchange [Member] |  |  |  |
Schedule Of Held To Maturity Securities [Line Items] |  |  |  |
Conversion of stock, description |  | During the second quarter of 2024, the Bank tendered all of its shares of Visa, Inc. (“Visa”) Class B-1 common stock in exchange for a combination of Visa Class B-2 common stock and Visa Class C common stock, pursuant to the terms and subject to the conditions of the public offering of Visa to exchange its Class B-1 common stock for a combination of shares of its Class B-2 common stock and Class C common stock, which expired on May 3, 2024. |  |
Gain on stock exchange | $ 20,600,000 |  |  |
Visa Stock Exchange [Member] | Class B-2 Common Stock [Member] |  |  |  |
Schedule Of Held To Maturity Securities [Line Items] |  |  |  |
Conversion of stock, shares converted | shares | 48,492 |  |  |
Cost basis | $ 0 |  |  |
Visa Stock Exchange [Member] | Class C Common Stock [Member] |  |  |  |
Schedule Of Held To Maturity Securities [Line Items] |  |  |  |
Conversion of stock, shares converted | shares | 19,245 |  |  |

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