Earnings Per Share - Reconciliation of Weighted Average Shares used for Basic and Diluted Earnings Per Share Calculation (Detail) - shares	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Earnings Per Share [Abstract]
Weighted average common shares	19,149,080	19,233,241	19,332,391
Add: Other common shares eligible for common dividends:
Restricted stock and RSUs	76,941	88,476	76,228
Diluted weighted average common shares	19,226,021	19,321,717	19,408,619

Weighted Average Number Of Shares Other [Abstract]

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- References

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- Definition

Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

+ References

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-Topic 718
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- Definition

The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 260
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-Name Accounting Standards Codification
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- Definition

Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 260
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