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Loans and Allowance for Credit Losses - Additional Information (Detail) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2024 USD ($) numberOfLoans | Dec. 31, 2023 USD ($) numberOfLoans | Dec. 31, 2022 USD ($) Contract | Dec. 31, 2021 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Non Accrual Status Of Loans After Number Of Days Past Due | 90 days |  |  |
Loans Receivable Held-for-sale, Amount | $ 51,991 | $ 29,820 |  |
Charge-offs | $ (35,428) | $ (33,267) | $ (9,845) |
Number of loans modified | 2,000 | 0 | 5 |
Total amount of loan modified |  |  | $ 676 |
Loans with modification to rate and payment due to amortization |  |  | 10 |
Minimum days required for conversion of trouble debt to be in default | 90 days |  |  |
Unearned Deferred (Fees) Costs on Loans | $ 14,700 | $ 8,200 |  |
Unearned Premiums | $ (18,900) | (25,700) |  |
Forecasted Value, National Unemployment, Percent | 4.17% |  |  |
Financing Receivable, Allowance for Credit Loss | $ 118,906 | 117,718 | 102,906 | $ 92,522
Weighted Average [Member] |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Forecasted Value, National Unemployment, Percent | 4.82% |  |  |
Maximum [Member] |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Forecasted Value, National Unemployment, Percent | 5.04% |  |  |
Impaired Loans [Member] |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Unfunded commitments related to nonperforming loans | $ 300 | 100 |  |
Loans To Individuals [Member] |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Non Accrual Status Of Loans After Number Of Days Past Due | 150 days |  |  |
Nonaccrual Commercial Loans [Member] |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Loans Receivable Held-for-sale, Amount | $ 0 | 0 |  |
Gain (loss) on sale of impaired loans | 0 | 0 | $ 0 |
SEC Schedule, 12-09, Reserve, Off-balance Sheet Activity [Member] | Impaired Loans [Member] |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Off-Balance-Sheet, Credit Loss, Liability | $ 0 | $ 0 |  |

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