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Investment Securities - Non-Marketable Securities Included in Other Assets (Details) - USD ($) | 9 Months Ended |  |
--- | --- | --- | ---
Sep. 30, 2024 | Sep. 30, 2023 | Oct. 24, 2024 | Dec. 31, 2023
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 | $ 1,700,000 |  |  | $ 2,000,000.0
Low income housing tax credits and other tax benefits | 394,000 |  |  |
Low income housing amortization expense | 328,000 |  |  |
Unfunded commitments for low income housing tax credit funds | 342,000 |  |  |
Impairment losses | 0 | $ 0 |  |
Subsequent event |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |
Federal home loan bank, dividend rate percentage |  |  | 8.75% |
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 Amortization Method Qualified Affordable Housing Project Investments, Tax Credits + References No definition available. + Details
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- Definition Amount of investment that generates income tax credit and other income tax benefit under tax credit program elected to be accounted for using proportional amortization method. Includes, but is not limited to, investment under program not meeting condition for accounting under proportional amortization method. + References Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Topic 740 -SubTopic 323 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478156/740-323-50-2 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 740 -SubTopic 323 -Name Accounting Standards Codification -Section 50 -Paragraph 1A -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478156/740-323-50-1A + Details
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