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v3.25.4

Securities Available for Sale and Held to Maturity - Additional Information (Details) - USD ($) | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Jun. 30, 2024 | Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Schedule of Available For Sale and Held to Maturity Securities [Line Items] |  |  |  |  |
Reclassification of Securities available for sale to securities held to maturity |  |  |  |  | $ 766,000,000
Net unrealized holding loss on AFS Securities at date of transfer |  |  |  |  | 91,900,000
Net unrealized holding losses on AFS Securities, net of tax at date of transfer |  |  |  |  | $ (68,900,000)
Net unamortized, unrealized loss on transfer of securities |  | $ 36,300,000 | $ 46,600,000 |  |
Credit loss recognized |  | 0 | 0 |  |
Expected credit losses, current. |  | 0 | 0 |  |
Reserve for securities held to maturity |  | 0 | 0 |  |
Securities held to maturity |  | 1,207,454,000 | 1,335,385,000 |  |
Securities available for sale |  | 1,876,830,000 | 1,692,534,000 |  |
Available for sale securities, average yield | 4.85% |  |  |  |
Gross realized losses | $ 182,800,000 | 0 | 182,792,000 | $ 8,000 |
Net unamortized, unrealized loss on transfer of securities, net of tax | (137,100,000) |  |  |  |
Purchases of securities available for sale | 1,378,000,000 | 317,685,000 | 1,555,065,000 | $ 0 |
Pledged to collateralize public deposits and securities sold under repurchase agreements and for other purposes as permitted by law |  | 1,709,000,000 | 1,910,000,000 |  |
Pledged securities providing additional contingency funding |  | 0 | 0 |  |
30 Days or More Past Due [Member] |  |  |  |  |
Schedule of Available For Sale and Held to Maturity Securities [Line Items] |  |  |  |  |
Securities held to maturity |  | 0 | 0 |  |
Securities Available for Sale [Member] |  |  |  |  |
Schedule of Available For Sale and Held to Maturity Securities [Line Items] |  |  |  |  |
Accrued interest receivable |  | 5,900,000 | 5,000,000 |  |
Securities Held to Maturity [Member] |  |  |  |  |
Schedule of Available For Sale and Held to Maturity Securities [Line Items] |  |  |  |  |
Accrued interest receivable |  | 2,100,000 | 2,400,000 |  |
Held-to-maturity nonnaccrual |  | $ 0 | $ 0 |  |
Investment Securities Portfolio [Member] |  |  |  |  |
Schedule of Available For Sale and Held to Maturity Securities [Line Items] |  |  |  |  |
Securities available for sale | $ 1,561,000,000 |  |  |  |
Available for sale securities, average yield | 1.36% |  |  |  |

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