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Investment Securities - Schedule of Bond Ratings For Held-to-Maturity Securities (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
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Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |
Debt securities, held-to-maturity | $ 109,036 | $ 137,413
Obligations of state and political subdivisions |  |
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items] |  |
Debt securities, held-to-maturity | 1,667 | $ 3,513
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 | 1,461 |
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 | $ 206 |

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