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Investment Securities - Non-Marketable Securities Included in Other Assets Narrative (Details) - USD ($) |  | 12 Months Ended |
--- | --- | --- | ---
Jul. 13, 2023 | Dec. 31, 2023 | Dec. 31, 2022 | Feb. 21, 2024
Schedule of Equity Method Investments [Line Items] |  |  |  |
Federal home loan bank stock, par value (in usd per share) |  | $ 100 |  |
Investments in low income housing tax credit funds |  | $ 2,000,000 | $ 2,500,000 |
Low income housing tax credits and other tax benefits |  | 600,000 |  |
Low income housing amortization expense |  | 503,000 |  |
Unfunded commitments for low income housing tax credit funds |  | 344,000 |  |
Impairment losses |  | $ 0 | $ 0 |
Subsequent event |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |
Federal home loan bank, dividend rate percentage |  |  |  | 8.75%
Visa Inc. Class B common stock |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |
Equity securities, FV-NI gain | $ 2,800,000 |  |  |
Visa Inc. Class B common stock |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |
Number of shares of securities carried at cost (in shares) |  | 10,439 | 10,439 |
Carrying value of securities carried at cost |  | $ 0 | $ 0 |
Other assets |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |
Federal home loan bank stock |  | $ 16,700,000 | $ 16,700,000 |

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