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Loans (CECL) - Additional Information (Detail) - USD ($) $ in Millions | Mar. 31, 2025 | Dec. 31, 2024
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Geneva in 2019 and Ossian State Bank in 2021 [Member] |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Accretable yield related to acquisition | $ 1.5 | $ 1.9

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