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Fair Value Measurements - Additional Information (Detail) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |  |
Transfers between Level 1, Level 2 and Level 3 securities | $ 0 | $ 0 |
Cash collateral deposit | 0 |  |
Notional value | 94,197,000 | 64,454,000 |
Proceeds from the sales and maturities of securities available-for-sale | 85,600,000 | 62,400,000 |
Purchases of investments | 87,800,000 | 93,400,000 |
Credit losses on available-for-sale securities | 0 | $ 0 | $ 0
Interest Rate Swap [Member] |  |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |  |
Notional value | $ 0 |  |

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