Restricted Stock and Stock Options - Restricted Stock Activity (Detail) - $ / shares	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
2012 Incentive Plan [Member] \| Common and Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares, Nonvested outstanding, Beginning balance	12,821	15,314	32,528
Shares, Granted	42,021	27,388	23,207
Shares, Vested	(44,311)	(29,881)	(40,421)
Shares, Nonvested outstanding, Ending balance	10,531	12,821	15,314
Weighted-Average Grant-Date Fair Value per Share, Beginning balance	$ 62.52	$ 60.23	$ 54.02
Weighted-Average Grant-Date Fair Value per Share, Granted	48.08	64.36	58.62
Weighted-Average Grant-Date Fair Value per Share, Vested	49.21	63.03	54.31
Weighted-Average Grant-Date Fair Value per Share, Ending balance	$ 60.92	$ 62.52	$ 60.23
2022 Incentive Plan [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares, Granted	2,098
Shares, Nonvested outstanding, Ending balance	2,098
Weighted-Average Grant-Date Fair Value per Share, Granted	$ 47.65
Weighted-Average Grant-Date Fair Value per Share, Ending balance	$ 47.65
2022 Incentive Plan [Member] \| Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares, Granted	22,826
Shares, Nonvested outstanding, Ending balance	22,826
Weighted-Average Grant-Date Fair Value per Share, Granted	$ 48.19
Weighted-Average Grant-Date Fair Value per Share, Ending balance	$ 48.19
Non-Employee Director Restricted Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares, Nonvested outstanding, Beginning balance	5,607	5,068	4,890
Shares, Granted	12,149	5,607	5,269
Shares, Vested	(5,868)	(5,068)	(5,091)
Shares, Nonvested outstanding, Ending balance	11,888	5,607	5,068
Weighted-Average Grant-Date Fair Value per Share, Beginning balance	$ 62.40	$ 69.03	$ 61.34
Weighted-Average Grant-Date Fair Value per Share, Granted	50.41	62.40	68.88
Weighted-Average Grant-Date Fair Value per Share, Vested	61.75	69.03	61.49
Weighted-Average Grant-Date Fair Value per Share, Ending balance	$ 50.47	$ 62.40	$ 69.03

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).

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued 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

+ Details

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ 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)(ii)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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

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- Definition

Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

+ 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)(i)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

+ References

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- Definition

The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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