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Investment Securities - Schedule of Bond Ratings For Held-to-Maturity Securities (Details) - USD ($) $ in Thousands | Jun. 30, 2024 | Dec. 31, 2023
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Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |
Debt securities, held-to-maturity | $ 904,610 | $ 925,198
Obligations of state and political subdivisions |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |
Debt securities, held-to-maturity | 61,798 | 62,034
Corporate bonds |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |
Debt securities, held-to-maturity | 30,000 | 30,000
Aaa / AAA | Obligations of state and political subdivisions |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |
Debt securities, held-to-maturity | 42,370 | 42,577
Aaa / AAA | Corporate bonds |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |
Debt securities, held-to-maturity | 0 | 0
Aa1 / AA+ | Obligations of state and political subdivisions |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |
Debt securities, held-to-maturity | 19,428 | 19,457
Aa1 / AA+ | Corporate bonds |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |
Debt securities, held-to-maturity | 0 | 0
A2 / A | Obligations of state and political subdivisions |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |
Debt securities, held-to-maturity | 0 | 0
A2 / A | Corporate bonds |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |
Debt securities, held-to-maturity | $ 30,000 | $ 30,000

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