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Securities - Additional Information (Details) $ in Thousands | 3 Months Ended |  |
--- | --- | --- | ---
Mar. 31, 2024 USD ($) segment | Mar. 31, 2023 USD ($) | Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($)
Securities |  |  |  |
Gains and losses from investment sales/calls realized | $ 0 | $ 0 |  |
Number of investment securities segregation for impairment evaluation | segment | 2 |  |  |
Cumulative credit loss charges recorded through earnings to date | $ 2,974 |  | $ 2,974 | $ 2,974
Unrealized losses | $ 171,480 |  | $ 157,845 |

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