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Investment Securities - Schedule of Bond Ratings For Held-to-Maturity Securities (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Dec. 31, 2024
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Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |
Held to maturity, amortized cost | $ 811,751 | $ 879,199
Obligations of state and political subdivisions |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |
Held to maturity, amortized cost | 61,204 | 61,560
Corporate bonds |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |
Held to maturity, amortized cost | 15,000 | 30,000
Aaa / AAA | Obligations of state and political subdivisions |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |
Held to maturity, amortized cost | 38,388 | 42,161
Aaa / AAA | Corporate bonds |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |
Held to maturity, amortized cost | 0 | 0
Aa1 / AA+ | Obligations of state and political subdivisions |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |
Held to maturity, amortized cost | 22,816 | 19,399
Aa1 / AA+ | Corporate bonds |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |
Held to maturity, amortized cost | 0 | 0
A2 / A | Obligations of state and political subdivisions |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |
Held to maturity, amortized cost | 0 | 0
A2 / A | Corporate bonds |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |
Held to maturity, amortized cost | $ 15,000 | $ 30,000

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