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Securities - Additional Information (Details) | 3 Months Ended | 6 Months Ended |  |
--- | --- | --- | --- | ---
Jun. 30, 2023 USD ($) Securities | Jun. 30, 2023 USD ($) Securities | Jan. 01, 2023 USD ($) | Dec. 31, 2022 USD ($) Securities
Debt and Equity Securities, FV-NI [Line Items] |  |  |  |
Debt securities held-to-maturity fair value | $ 351,825,000 | $ 351,825,000 |  | $ 353,901,000
Allowance for credit loss | 0 | 0 | $ 7,200,000 |
Other-than-temporary Impairment Loss, Debt Securities, Available-for-Sale | $ 0 | $ 0 |  |
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions | Securities | 601 | 601 |  | 611
US Treasury Securities [Member] | AA or Better [Member] |  |  |  |
Debt and Equity Securities, FV-NI [Line Items] |  |  |  |
Debt Securities, Percent | 100.00% | 100.00% |  |
US States and Political Subdivisions Debt Securities [Member] |  |  |  |
Debt and Equity Securities, FV-NI [Line Items] |  |  |  |
Debt securities held-to-maturity fair value | $ 163,204,000 | $ 163,204,000 |  | $ 162,536,000
US States and Political Subdivisions Debt Securities [Member] | A Rated [Member] |  |  |  |
Debt and Equity Securities, FV-NI [Line Items] |  |  |  |
Debt Securities, Percent | 11.00% | 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 | 86.00% | 86.00% |  |
US States and Political Subdivisions Debt Securities [Member] | Unrated [Member] |  |  |  |
Debt and Equity Securities, FV-NI [Line Items] |  |  |  |
Debt Securities, Percent | 3.00% | 3.00% |  |
Collateralized Mortgage-Backed Securities [Member] |  |  |  |
Debt and Equity Securities, FV-NI [Line Items] |  |  |  |
Debt securities held-to-maturity fair value | $ 168,541,000 | $ 168,541,000 |  | $ 170,605,000
Collateralized Mortgage-Backed Securities [Member] | AA [Member] |  |  |  |
Debt and Equity Securities, FV-NI [Line Items] |  |  |  |
Debt Securities, Percent | 38.00% | 38.00% |  |
Collateralized Mortgage-Backed Securities [Member] | AAA [Member] |  |  |  |
Debt and Equity Securities, FV-NI [Line Items] |  |  |  |
Debt Securities, Percent | 37.00% | 37.00% |  |
Collateralized Mortgage-Backed Securities [Member] | Unrated [Member] |  |  |  |
Debt and Equity Securities, FV-NI [Line Items] |  |  |  |
Debt Securities, Percent | 25.00% | 25.00% |  |

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