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Investment Securities - Narrative (Details) | 6 Months Ended |  |  |
--- | --- | --- | --- | ---
Jun. 30, 2024 USD ($) company state bond security | Jun. 30, 2023 USD ($) security | Dec. 31, 2023 USD ($) security | Dec. 31, 2022 USD ($) | Sep. 30, 2014 USD ($)
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
AFS allowance | $ 0 |  |  |  |
HTM allowance for credit losses | 149,000 | $ 428,000 | $ 434,000 | $ 0 |
Amortized Cost | 377,671,000 | 390,415,000 | $ 385,669,000 |  |
Gains or losses on the sale of securities | $ 0 | $ 0 |  |  |
Number of securities temporarily impaired (security) | security | 238 | 235 | 226 |  |
Financing receivable, threshold period past due | 30 days |  |  |  |
Debt securities, held-to-maturity, nonaccrual | $ 0 |  |  |  |
Amortized cost of securities transferred |  |  |  |  | $ 89,780,000
Fair value of securities transferred |  |  |  |  | 89,757,000
Net unrealized loss, net of taxes on transferred securities |  |  |  |  | $ 15,000
Unamortized balance of net unrealized losses transferred | $ 51,000 | $ 59,000 | $ 56,000 |  |
Number of states | state | 6 |  |  |  |
FHLB stock investment | $ 6,073,000 | 4,190,000 | 2,348,000 |  |
Federal reserve bank stock | 1,037,000 | 1,037,000 | 1,037,000 |  |
Impairment losses | 0 |  |  |  |
Other equity securities |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
Securities pledged as collateral | 310,931,000 | 329,615,000 | 340,623,000 |  |
Agency and mortgage-backed securities |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
HTM allowance for credit losses | $ 0 |  |  |  |
Municipal Bonds |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
Number of private activity bonds | bond | 2 |  |  |  |
Amortized Cost | $ 19,294,000 |  |  |  |
Corporate securities |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
HTM allowance for credit losses | 56,000 | 204,000 | 212,000 | $ 0 |
Amortized Cost | $ 32,250,000 | 34,750,000 | 34,750,000 |  |
Number of individual companies | company | 13 |  |  |  |
U.S. Treasury & Agency securities |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
HTM allowance for credit losses | $ 0 |  |  |  |
Amortized Cost | $ 38,100,000 | $ 40,100,000 | $ 40,100,000 |  |

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