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Stock Based Compensation - 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 | Apr. 27, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Percentage of option vesting rate |  |  | 20.00% |  |  |
Duration of options granted, years |  |  | 10 years |  |  |
Stock options outstanding, exercise price range, lower |  |  | $ 16.95 |  |  |
Stock options outstanding, exercise price range, upper |  |  | $ 48.91 |  |  |
Total unrecognized compensation cost related to nonvested share-based compensation arrangements granted under the Plan | $ 5,376,000 |  | $ 5,376,000 |  |  |
Weighted-average period of unrecognized compensation cost recognition, years |  |  | 1 year 2 months 8 days |  |  |
Total fair value of shares vested |  |  | $ 2,791,000 | $ 2,131,000 |  |
Stock compensation expense | 639,000 | $ 546,000 | 1,976,000 | 1,516,000 |  |
Dividends Payable | 27,263,000 | 25,739,000 | 27,263,000 | 25,739,000 | $ 25,753,000 |
Maximum [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Performance measurement amount in assets | 50,000,000,000 |  | 50,000,000,000 |  |  |
Minimum [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Performance measurement amount in assets | $ 10,000,000,000 |  | $ 10,000,000,000 |  |  |
Two Thousand Twenty One Omnibus Stock and Incentive Plan [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Shares of stock for issuance under the plan | 880,955 |  | 880,955 |  |  | 2,500,000
2021 Plan [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Percentage of option vesting rate |  |  | 20.00% |  |  |
Other Liabilities [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Dividends Payable | $ 152,000 | 112,000 | $ 152,000 | 112,000 | $ 141,000 |
Restricted Stock [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Total fair value of shares vested |  |  | 2,808,000 | 2,276,000 |  |
Restricted Stock [Member] | Director [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Stock compensation expense | 210,000 | 187,000 | $ 607,000 | 537,000 |  |
Employee Stock Option |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Restricted shares vesting period |  |  | 2 years |  |  |
Percentage of option vesting rate |  |  | 20.00% |  |  |
Performance share [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Percentage of option vesting rate |  |  | 33.30% |  |  |
Performance share [Member] | Maximum [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Issued Upon Vesting Based On Core Return Percentage |  |  | 200.00% |  |  |
Performance share [Member] | Minimum [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Issued Upon Vesting Based On Core Return Percentage |  |  | 0.00% |  |  |
Performance share [Member] | Executives And Other Officers [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Restricted shares vesting period |  |  | 3 years |  |  |
Criteria period |  |  | 3 years |  |  |
Average adjusted earnings per share growth percentage |  |  | 50.00% |  |  |
Return on average assets |  |  | 100.00% |  |  |
Performance share [Member] | Executives And Other Officers [Member] | Maximum [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Issued Upon Vesting Based On Core Return Percentage |  |  | 200.00% |  |  |
Performance share [Member] | Executives And Other Officers [Member] | Minimum [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Issued Upon Vesting Based On Core Return Percentage |  |  | 0.00% |  |  |
Restricted Stock Units [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Percentage of option vesting rate |  |  | 33.30% |  |  |
Total unrecognized compensation cost related to nonvested share-based compensation arrangements granted under the Plan | 5,859,000 | 4,920,000 | $ 5,859,000 | $ 4,920,000 |  |
Weighted-average period of unrecognized compensation cost recognition, years |  |  | 1 year 1 month 24 days | 1 year 2 months 8 days |  |
Restricted Stock Units [Member] | Employee [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Stock compensation expense | $ 751,000 | $ 521,000 | $ 2,474,000 | $ 1,381,000 |  |

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