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Fair Value Measurements - 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
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |  |  |  |
Purchases of investments |  |  | $ 59,000,000 | $ 89,400,000 |
Proceeds from the sales and maturities of securities available-for-sale |  |  | 58,400,000 | 58,900,000 |
Transfers between Level 1, Level 2 and Level 3 securities |  |  | 0 | 0 |
Cash collateral deposit | $ 1,000,000 |  | 1,000,000 |  |
Notional value | 67,723,000 |  | 67,723,000 |  | $ 64,454,000
Credit losses on available-for-sale securities | 0 | $ 0 | 0 | $ 0 |
Interest Rate Swap [Member] |  |  |  |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |  |  |  |
Notional value | $ 25,000,000 |  | $ 25,000,000 |  |

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