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Capital Management - Additional Information (Detail) - USD ($) | 12 Months Ended | 166 Months Ended |
--- | --- | --- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2023 | Oct. 31, 2016
Equity [Abstract] |  |  |  |  |
Share repurchase program, new limit amount |  |  |  |  | $ 25,000,000
Shares repurchased under the program | 46,741 | 264,449 | 0 |  |
Shares repurchased under the program, value | $ 2,200,000 | $ 12,400,000 |  |  |
Shares repurchased, value | $ 36,929,000 | $ 34,758,000 |  | $ 36,929,000 |
Shares repurchased, average price | $ 46.45 | $ 46.84 |  | $ 23.53 |
Shares repurchased | 1,569,440 | 1,522,699 |  | 1,569,440 |
Quarterly dividend per share | $ 0.34 | $ 0.31 | $ 0.29 | $ 0.34 |
Extraordinary dividends declared per share | $ 3.50 | $ 4.00 | $ 4.00 |  |

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