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Investment Securities - Non-Marketable Securities Included in Other Assets (Details) - USD ($) |  | 9 Months Ended |  |
--- | --- | --- | --- | ---
Jul. 13, 2023 | Sep. 30, 2023 | Sep. 30, 2022 | Oct. 26, 2023 | Dec. 31, 2022
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 |  | $ 2,100,000 |  |  | $ 2,500,000
Low income housing tax credits and other tax benefits |  | 450,000 |  |  |
Low income housing amortization expense |  | 377,000 |  |  |
Unfunded commitments for low income housing tax credit funds |  | 346,000 |  |  |
Subsequent event |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |
Federal home loan bank, dividend rate percentage |  |  |  | 8.25% |
Visa Inc. Class B common stock |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |
Equity securities, FV-NI gain | $ 2,800,000 |  |  |  |
Low-income housing tax credit investment |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |
Impairment losses |  | 0 | $ 0 |  |
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
Carrying value of securities carried at cost |  | 0 |  |  |
Asset Derivatives |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |
Federal home loan bank stock |  | $ 16,700,000 |  |  | $ 16,700,000

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- Definition Amount of investment in qualified affordable housing projects. + References Reference 1: http://www.xbrl.org/2003/role/recommendedDisclosureRef -Topic 323 -SubTopic 740 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481543/323-740-50-2 + Details
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