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Earnings Per Share - Reconciliation of Weighted Average Shares used for Basic and Diluted Earnings Per Share Calculation (Detail) - shares	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Earnings Per Share [Abstract]
Weighted average common shares	19,070,717	19,149,080	19,233,241
Add: Other common shares eligible for common dividends:
Restricted stock and RSUs	89,088	76,941	88,476
Diluted weighted average common shares	19,159,805	19,226,021	19,321,717

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Weighted Average Number Of Shares Other [Abstract]

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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480454/718-10-45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 260
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-Section 50
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 260
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 260
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 260
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-Publisher FASB
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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
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482662/260-10-50-1

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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
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482662/260-10-50-1

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