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Securities - Narrative (Details) - USD ($) | 3 Months Ended | 9 Months Ended | 21 Months Ended |
--- | --- | --- | --- | ---
Sep. 30, 2025 | Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Dec. 31, 2024
Marketable Securities [Line Items] |  |  |  |  |
Securities available-for-sale, at fair value | $ 511,095,000 | $ 511,095,000 |  | $ 511,095,000 | $ 482,328,000
Debt Securities, Available-for-Sale, Excluding Accrued Interest | 511,095,000 | 511,095,000 |  | 511,095,000 | 482,328,000
Provision for credit losses, HTM |  |  |  | 0 |
Provision for credit losses, AFS |  |  |  | 0 |
Impairment on other investments |  | 0 |  |  |
Asset Pledged as Collateral | Secure Public Funds and Securities Sold under Agreements to Repurchase |  |  |  |  |
Marketable Securities [Line Items] |  |  |  |  |
Securities available-for-sale, at fair value | 404,600,000 | 404,600,000 |  | 404,600,000 | 432,600,000
Debt Securities, Available-for-Sale, Excluding Accrued Interest | 404,600,000 | 404,600,000 |  | $ 404,600,000 | $ 432,600,000
Gross gains | $ 210,000 |  | $ 0 |  |
Realized losses |  | $ 3,900,000 | $ 0 |  |

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- Definition Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 326 -SubTopic 30 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479130/326-30-45-1 + Details
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