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Investment Securities (Details Textual) - USD ($) shares in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2024 | Mar. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Schedule of Investment Securities Information [Line Items] |  |  |  |  |  |  |
Proceeds from Sale of Debt Securities, Available-for-sale | $ 1,100,000,000 |  | $ 715,000,000 |  | $ 1,141,231,000 | $ 715,066,000 | $ 110,177,000
Gain (Loss) on Sale of Investments |  |  |  |  | 148,000,000 | 65,000,000 |
Visa B Shares, Amount Sold |  |  | 1 |  |  |  |
Debt Instrument, Collateral Amount | 1,500,000,000 |  | $ 1,600,000,000 |  | 1,500,000,000 | 1,600,000,000 |
Interest Receivable | 167,772,000 |  | 169,569,000 |  | 167,772,000 | 169,569,000 |
Held to maturity allowance for credit loss | (60,000) |  | (75,000) |  | (60,000) | (75,000) |
Federal Home Loan Bank Stock | 92,000,000 |  | 143,000,000 |  | 92,000,000 | 143,000,000 |
Federal Reserve Bank Stock | 88,000,000 |  | 87,000,000 |  | 88,000,000 | 87,000,000 |
Equity Securities with Readily Determined Fair Value | 11,000,000 |  | 7,000,000 |  | 11,000,000 | 7,000,000 |
Equity Securities without Readily Determinable Fair Value, Amount | 13,000,000 |  | 35,000,000 |  | 13,000,000 | 35,000,000 |
Held-to-Maturity Securities [Member] |  |  |  |  |  |  |
Schedule of Investment Securities Information [Line Items] |  |  |  |  |  |  |
Interest Receivable | 18,000,000 |  | 18,000,000 |  | 18,000,000 | 18,000,000 |
Available-for-sale Securities [Member] |  |  |  |  |  |  |
Schedule of Investment Securities Information [Line Items] |  |  |  |  |  |  |
Gain (Loss) on Sale of Investments | (148,000,000) |  | (65,000,000) |  |  |  |
Interest Receivable | 21,000,000 |  | 15,000,000 |  | 21,000,000 | 15,000,000 |
Federal Home Loan Bank Certificates and Obligations (FHLB) [Member] |  |  |  |  |  |  |
Schedule of Investment Securities Information [Line Items] |  |  |  |  |  |  |
Interest Receivable | 2,000,000 |  | 4,000,000 |  | 2,000,000 | 4,000,000 |
US States and Political Subdivisions Debt Securities [Member] |  |  |  |  |  |  |
Schedule of Investment Securities Information [Line Items] |  |  |  |  |  |  |
Proceeds from Sale of Debt Securities, Available-for-sale |  |  |  | $ 110,000,000 |  |  |
Gain (Loss) on Sale of Investments |  |  |  | $ 2,000,000 |  |  |
Visa B Shares |  |  |  |  |  |  |
Schedule of Investment Securities Information [Line Items] |  |  |  |  |  |  |
Gain (Loss) on Sale of Investments |  | $ 4,000,000 | 6,000,000 |  |  |  |
Federal Reserve Bank Stock [Member] |  |  |  |  |  |  |
Schedule of Investment Securities Information [Line Items] |  |  |  |  |  |  |
Interest Receivable | 0 |  | 0 |  | 0 | 0 |
Mortgage-Backed Securities, Issued by US Government Sponsored Enterprises [Member] |  |  |  |  |  |  |
Schedule of Investment Securities Information [Line Items] |  |  |  |  |  |  |
Held to maturity allowance for credit loss | 0 |  | 0 |  | 0 | 0 |
US Treasury Securities [Member] |  |  |  |  |  |  |
Schedule of Investment Securities Information [Line Items] |  |  |  |  |  |  |
Held to maturity allowance for credit loss | 0 |  | 0 |  | 0 | 0 |
US States and Political Subdivisions Debt Securities [Member] |  |  |  |  |  |  |
Schedule of Investment Securities Information [Line Items] |  |  |  |  |  |  |
Held to maturity allowance for credit loss | $ 0 |  | $ 0 |  | $ 0 | $ 0 |

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