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Investment Securities - Schedule of Bond Ratings For Held-to-Maturity Securities (Details) - USD ($) $ in Thousands | Sep. 30, 2023 | Dec. 31, 2022
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Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |
Debt securities, held-to-maturity | $ 935,142 | $ 972,207
Obligations of state and political subdivisions |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |
Debt securities, held-to-maturity | 62,151 | 62,500
Corporate bonds |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |
Debt securities, held-to-maturity | 30,000 | 30,000
Moody's And/Or Standard & Poor's AAA Rating | Obligations of state and political subdivisions |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |
Debt securities, held-to-maturity | 42,680 | 42,986
Moody's And/Or Standard & Poor's AAA Rating | Corporate bonds |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |
Debt securities, held-to-maturity | 0 | 0
Moody's And/Or Standard & Poor's AA Rating | Obligations of state and political subdivisions |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |
Debt securities, held-to-maturity | 19,471 | 19,514
Moody's And/Or Standard & Poor's AA Rating | Corporate bonds |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |
Debt securities, held-to-maturity | 0 | 0
Moody's And/Or Standard & Poor's A Rating | Obligations of state and political subdivisions |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |
Debt securities, held-to-maturity | 0 | 0
Moody's And/Or Standard & Poor's A Rating | 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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