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Securities - Additional Information (Details) $ in Thousands | Mar. 31, 2024 USD ($) Securities | Dec. 31, 2023 Securities | Mar. 31, 2023 USD ($)
--- | --- | --- | ---
Debt and Equity Securities, FV-NI [Line Items] |  |  |
Allowance for credit loss | $ | $ 0 |  | $ 0
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions | Securities | 570 | 569 |
US Treasury Securities [Member] | AA or Better [Member] |  |  |
Debt and Equity Securities, FV-NI [Line Items] |  |  |
Debt Securities, Percent | 100.00% |  |
US States and Political Subdivisions Debt Securities [Member] | A Rated [Member] |  |  |
Debt and Equity Securities, FV-NI [Line Items] |  |  |
Debt Securities, Percent | 11.00% |  |
US States and Political Subdivisions Debt Securities [Member] | AA or Better [Member] |  |  |
Debt and Equity Securities, FV-NI [Line Items] |  |  |
Debt Securities, Percent | 85.00% |  |
US States and Political Subdivisions Debt Securities [Member] | Unrated [Member] |  |  |
Debt and Equity Securities, FV-NI [Line Items] |  |  |
Debt Securities, Percent | 4.00% |  |
Collateralized Mortgage-Backed Securities [Member] | AA [Member] |  |  |
Debt and Equity Securities, FV-NI [Line Items] |  |  |
Debt Securities, Percent | 40.00% |  |
Collateralized Mortgage-Backed Securities [Member] | AAA [Member] |  |  |
Debt and Equity Securities, FV-NI [Line Items] |  |  |
Debt Securities, Percent | 40.00% |  |
Collateralized Mortgage-Backed Securities [Member] | Unrated [Member] |  |  |
Debt and Equity Securities, FV-NI [Line Items] |  |  |
Debt Securities, Percent | 20.00% |  |

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