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Restricted Stock Units Issued (Detail) - Restricted Stock Units (RSUs) - $ / shares	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Restricted Stock Units
Beginning Restricted Stock Units	49,182	43,192
Restricted Stock Units Granted	3,595	4,519
Dividend Equivalents Earned	1,258	1,471
Restricted Stock Units Settled	10,236
Ending Restricted Stock Units	43,799	49,182
Weighted-Average Stock Price
Beginning Restricted Stock Units	$ 41.67	$ 41.34
Restricted Stock Units Granted	46.72	43.35
Dividend Equivalents Earned	53.20	46.34
Restricted Stock Units Settled	51.28
Ending Restricted Stock Units	$ 40.17	$ 41.67

X

- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(01)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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