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Securities - Additional Information (Detail) - USD ($) | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024 | Dec. 31, 2024
Schedule of Available-for-sale Securities [Line Items] |  |  |  |  |
Investments pledged, carrying value | $ 238,100,000 |  | $ 238,100,000 |  | $ 221,900,000
Other securities | 11,509,000 |  | 11,509,000 |  | 14,400,000
Proceeds from sales of securities |  |  | 1,374,000 | $ 0 |
Gross realized gain (losses) | 0 | $ 0 | 0 | $ 0 |
Federal Home Loan Bank of Cincinnati and Indianapolis Stock [Member] |  |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |  |
Other securities | 11,500,000 |  | 11,500,000 |  | 14,400,000
Federal Reserve's Bank Term Funding Program [Member] |  |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |  |
Investments pledged, carrying value | $ 29,000,000 |  | $ 29,000,000 |  | $ 29,900,000

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