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Securities - Additional Information (Details) $ in Thousands | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2024 USD ($) Securities | Sep. 30, 2023 USD ($) | Sep. 30, 2024 USD ($) Securities | Sep. 30, 2023 USD ($) | Dec. 31, 2023 Securities
Debt and Equity Securities, FV-NI [Line Items] |  |  |  |  |
Allowance for credit loss | $ | $ 0 | $ 0 | $ 0 | $ 0 |
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions | Securities | 541 |  | 541 |  | 569
US Treasury Securities [Member] | AA or Better [Member] |  |  |  |  |
Debt and Equity Securities, FV-NI [Line Items] |  |  |  |  |
Debt Securities, Percent | 100.00% |  | 100.00% |  |
US States and Political Subdivisions Debt Securities [Member] | A Rated [Member] |  |  |  |  |
Debt and Equity Securities, FV-NI [Line Items] |  |  |  |  |
Debt Securities, Percent | 10.00% |  | 10.00% |  |
US States and Political Subdivisions Debt Securities [Member] | AA or Better [Member] |  |  |  |  |
Debt and Equity Securities, FV-NI [Line Items] |  |  |  |  |
Debt Securities, Percent | 86.00% |  | 86.00% |  |
US States and Political Subdivisions Debt Securities [Member] | Unrated [Member] |  |  |  |  |
Debt and Equity Securities, FV-NI [Line Items] |  |  |  |  |
Debt Securities, Percent | 4.00% |  | 4.00% |  |
Collateralized Mortgage-Backed Securities [Member] | AA [Member] |  |  |  |  |
Debt and Equity Securities, FV-NI [Line Items] |  |  |  |  |
Debt Securities, Percent | 42.00% |  | 42.00% |  |
Collateralized Mortgage-Backed Securities [Member] | AAA [Member] |  |  |  |  |
Debt and Equity Securities, FV-NI [Line Items] |  |  |  |  |
Debt Securities, Percent | 43.00% |  | 43.00% |  |
Collateralized Mortgage-Backed Securities [Member] | Unrated [Member] |  |  |  |  |
Debt and Equity Securities, FV-NI [Line Items] |  |  |  |  |
Debt Securities, Percent | 15.00% |  | 15.00% |  |

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- Definition Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset. + References Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (b)(3) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481800/320-10-50-6 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Subparagraph (b)(3) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479106/326-30-50-4 + Details
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