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Derivative Financial Instruments - Schedule of Effects of Interest Rate Swap Agreements on Consolidated Statements of Income (Detail) - Designated as Hedging Instrument [Member] - Interest Rate Swap [Member] - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2025 | Jun. 30, 2024 | Jun. 30, 2025 | Jun. 30, 2024
Loans, Including Fees [Member] |  |  |  |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |  |  |
Effects of derivatives on consolidated statement of income | $ (21) | $ 19 | $ (45) | $ 5
Other [Member] |  |  |  |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |  |  |
Effects of derivatives on consolidated statement of income | 25 | 216 | 50 | 427
Interest Income [Member] |  |  |  |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |  |  |
Effects of derivatives on consolidated statement of income | $ 4 | $ 235 | $ 5 | $ 432

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