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Allowance for Credit Losses - Schedule of Held-to-Maturity Debt Securities by Credit Quality Indicator (Details) - USD ($) $ in Thousands | Dec. 31, 2025 | Dec. 31, 2024
--- | --- | ---
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |
Amortized Cost | $ 3,344,165 | $ 3,613,720
Less: Allowance for credit losses | (260) | (457)
Held-to-maturity securities, net of allowance for credit losses | 3,343,905 | 3,613,263
U.S. government agencies |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |
2025 | 0 |
2024 | 0 |
2023 | 0 |
2022 | 135,000 |
2021 | 147,830 |
Prior | 30,711 |
Amortized Cost | 313,541 | 313,539
U.S. government agencies | 1-4 internal grade |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |
2025 | 0 |
2024 | 0 |
2023 | 0 |
2022 | 135,000 |
2021 | 147,830 |
Prior | 30,711 |
Amortized Cost | 313,541 |
U.S. government agencies | 5-7 internal grade |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |
2025 | 0 |
2024 | 0 |
2023 | 0 |
2022 | 0 |
2021 | 0 |
Prior | 0 |
Amortized Cost | 0 |
U.S. government agencies | 8-10 internal grade |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |
2025 | 0 |
2024 | 0 |
2023 | 0 |
2022 | 0 |
2021 | 0 |
Prior | 0 |
Amortized Cost | 0 |
Municipal |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |
2025 | 0 |
2024 | 0 |
2023 | 4,092 |
2022 | 1,027 |
2021 | 6,718 |
Prior | 132,355 |
Amortized Cost | 144,192 | $ 161,016
Municipal | 1-4 internal grade |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |
2025 | 0 |
2024 | 0 |
2023 | 4,092 |
2022 | 1,027 |
2021 | 6,718 |
Prior | 130,468 |
Amortized Cost | 142,305 |
Municipal | 5-7 internal grade |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |
2025 | 0 |
2024 | 0 |
2023 | 0 |
2022 | 0 |
2021 | 0 |
Prior | 1,887 |
Amortized Cost | 1,887 |
Municipal | 8-10 internal grade |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |
2025 | 0 |
2024 | 0 |
2023 | 0 |
2022 | 0 |
2021 | 0 |
Prior | 0 |
Amortized Cost | 0 |
Mortgage-backed securities |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |
2025 | 0 |
2024 | 0 |
2023 | 273,577 |
2022 | 480,317 |
2021 | 2,097,441 |
Prior | 0 |
Amortized Cost | 2,851,335 |
Mortgage-backed securities | 1-4 internal grade |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |
2025 | 0 |
2024 | 0 |
2023 | 273,577 |
2022 | 480,317 |
2021 | 2,097,441 |
Prior | 0 |
Amortized Cost | 2,851,335 |
Mortgage-backed securities | 5-7 internal grade |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |
2025 | 0 |
2024 | 0 |
2023 | 0 |
2022 | 0 |
2021 | 0 |
Prior | 0 |
Amortized Cost | 0 |
Mortgage-backed securities | 8-10 internal grade |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |
2025 | 0 |
2024 | 0 |
2023 | 0 |
2022 | 0 |
2021 | 0 |
Prior | 0 |
Amortized Cost | 0 |
Corporate notes |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |
2025 | 0 |
2024 | 0 |
2023 | 0 |
2022 | 4,973 |
2021 | 0 |
Prior | 30,124 |
Amortized Cost | 35,097 |
Corporate notes | 1-4 internal grade |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |
2025 | 0 |
2024 | 0 |
2023 | 0 |
2022 | 4,973 |
2021 | 0 |
Prior | 30,124 |
Amortized Cost | 35,097 |
Corporate notes | 5-7 internal grade |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |
2025 | 0 |
2024 | 0 |
2023 | 0 |
2022 | 0 |
2021 | 0 |
Prior | 0 |
Amortized Cost | 0 |
Corporate notes | 8-10 internal grade |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |
2025 | 0 |
2024 | 0 |
2023 | 0 |
2022 | 0 |
2021 | 0 |
Prior | 0 |
Amortized Cost | $ 0 |

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