Earnings per Common Share - Computation of Basic and Diluted Earnings per Common Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Basic
Net income	$ 8,366	$ 10,387	$ 21,790	$ 33,309
Less allocation of earnings and dividends to participating securities	177	388	455	1,220
Net income available to common shareholders-basic	$ 8,189	$ 9,999	$ 21,335	$ 32,089
Weighted average common shares outstanding	15,736,966	15,735,007	15,720,714	15,747,648
Less average participating securities	332,531	588,715	328,447	576,902
Weighted average number of shares outstanding used in the calculation of basic earnings per common share	15,404,435	15,146,292	15,392,267	15,170,746
Earnings per common share:
Basic	$ 0.53	$ 0.66	$ 1.39	$ 2.12
Diluted	$ 0.53	$ 0.66	$ 1.39	$ 2.12

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Weighted average number of common shares outstanding.

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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This element represents nonvested share-based payment awards that contain non-forfeitable rights to dividends or dividend equivalents (whether paid or unpaid). Basic and dilutive earnings per share are generally disclosed for such shares using the two-class method.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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