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Fair Values of Assets and Liabilities - Additional Information (Detail) - USD ($) | 12 Months Ended
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Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |
Random sample percentage of securities for each quarter | 100.00% |  |
Total gains or losses included in earnings |  | $ 0 |
Interest rate swaps transferred into Level 3 from Level 2 | $ 69,000 | 0 |
Corporate securities transferred from Level 3 to Level 2 | 0 | 0 |
Impaired loans considered to be credit risk of non-collection | 250,000 |  |
Updated appraisal requirement floor | 250,000 |  |
Other real estate owned | 422,000 | 534,000 |
Financial instrument of credit risk | 100,000 | 100,000 |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings On Assets Held At Year End | 0 |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Between Levels 1 And 2 | 0 | 0 |
Provision for credit losses | 17,759,000 | 17,521,000 | $ (377,000)
Other Assets [Member] |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |
Total gains or losses included in earnings | 0 | 0 |
Interest rate swaps transferred into Level 3 from Level 2 | 57,000 |  |
Corporate securities transferred from Level 3 to Level 2 | $ 0 | $ 0 |

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- Definition Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Between Levels 1 And 2 + References No definition available. + Details
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- Definition Impaired loans fair value non collection. + References No definition available. + Details
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