Stock-Based Compensation Plans - Schedule of Plans' Restricted and Performance Share Award Activity (Details) - $ / shares	9 Months Ended
Sep. 30, 2024	Sep. 30, 2023
Restricted shares
Common Shares
Outstanding, beginning of the period (in shares)	746,123	610,155
Granted (in shares)	405,506	268,142
Vested and issued (in shares)	(238,002)	(117,365)
Expired, canceled or forfeited (in shares)	(17,885)	(12,491)
Outstanding, end of the period (in shares)	895,742	748,441
Vested, but deferred (in shares)	100,281	98,747
Weighted Average Grant-Date Fair Value
Outstanding, beginning of period (usd per share)	$ 79.60	$ 73.21
Granted (usd per share)	99.78	88.18
Vested and issued (usd per share)	70.14	65.51
Canceled or forfeited (usd per share)	92.77	83.47
Outstanding, end of period (usd per share)	90.99	79.61
Vested, but deferred (usd per share)	$ 54.19	$ 53.46
Performance-based stock
Common Shares
Outstanding, beginning of the period (in shares)	553,026	545,379
Granted (in shares)	111,398	189,219
Added by performance factor at vesting (in shares)	96,952	23,161
Vested and issued (in shares)	(296,243)	(178,203)
Expired, canceled or forfeited (in shares)	(5,304)	(19,289)
Outstanding, end of the period (in shares)	459,829	560,267
Vested, but deferred (in shares)	21,688	36,465
Weighted Average Grant-Date Fair Value
Outstanding, beginning of period (usd per share)	$ 79.69	$ 70.30
Granted (usd per share)	100.44	92.37
Added by performance factor at vesting (usd per share)	58.78	63.64
Vested and issued (usd per share)	58.76	63.64
Canceled or forfeited (usd per share)	95.77	82.14
Outstanding, end of period (usd per share)	93.61	79.18
Vested, but deferred (usd per share)	$ 44.21	$ 45.08

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

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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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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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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).

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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
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(ii)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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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.

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- Definition

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

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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

Share-Based Compensation Arrangement By Share-Based Payment Award, Equity Instruments Other Than Options, Added By Performance Factor At Vesting

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Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested but not Issuable in Period

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Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested but not Issuable in Period, Weighted Average Grant Date Fair Value

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