Number of common shares of the entity that have been issued in settlement of vested units.

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Represents the duration of performance targets.

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No definition available.

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Represents the number of stock grants made during the period on the basis of service and performance criteria 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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No definition available.

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The number of shares reserved for future grants including all plans.

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No definition available.

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Consists of the right to receive share of common stock.

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Amount of decrease to equity for grantee's tax withholding obligation for award under share-based payment arrangement.

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No definition available.

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (i)
-Publisher FASB
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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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-Topic 718
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- Definition

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.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
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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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No definition available.

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

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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
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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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Stock-Based Compensation Plans - RSUs and PSUs additional (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Feb. 29, 2024
Additional share-based compensation disclosures
Total unrecognized compensation cost		$ 64.7
Weighted average recognition period for unrecognized compensation cost (in years)		1 year 7 months 6 days
RSUs, 2023 grants
Units
Share of common stock		1
Changes
Granted (in shares)		109,683
RSUs, 2022 grants
Units
Share of common stock			1
Changes
Granted (in shares)			192,798
RSUs, 2021 grant
Units
Share of common stock				1
Changes
Granted (in shares)				191,139
PSUs, 2023 grants
Changes
Granted (in shares)		84,129
PSUs, 2022 grants
Changes
Granted (in shares)			112,451
PSUs, 2021 grant
Changes
Granted (in shares)				127,356
Restricted stock units (RSUs) and performance stock units (PSUs)
Units
Vesting period (in years)		3 years	3 years	3 years
The number of grants made during the year on the basis of service and/or performance criteria other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).		193,812	305,249	318,495
Payments to tax authorities on employees' behalf for shares withheld related to share settlements		$ 54.1	$ 39.7	$ 21.2
Changes
Unvested at the beginning of the year (in units)	437,239	582,012
Granted (in shares)		193,812
Vested (in units)		(310,485)
Cancelled or forfeited (in units)		(28,100)
Unvested at the end of the year (in units)		437,239	582,012
Shares reserved for future grants (all plans)		1,539,738
Weighted Average Grant Date Fair Value
Unvested at the beginning of the year (in dollars per unit)	$ 213.06	$ 164.60
Granted (in dollars per unit)		247.90	$ 187.31	$ 141.41
Vested (in dollars per unit)		146.27
Cancelled or forfeited (in dollars per unit)		187.55
Unvested at the end of the year (in dollars per unit)		$ 213.06	$ 164.60
Additional share-based compensation disclosures
Fair value of vested units		$ 123.8	$ 147.2	$ 126.0
Restricted stock and RSUs
Units
Performance target period (in years)		3 years	3 years	3 years
Performance stock units (PSUs)
Units
Vesting period (in years)		3 years
Performance target period (in years)	3 years	3 years	3 years
Changes
Vested (in units)		(132,787)
Settled (in shares)					(265,574)
Maximum \| PSUs, 2023 grants
Units
Share of common stock		2
Maximum \| PSUs, 2022 grants
Units
Share of common stock			2
Maximum \| PSUs, 2021 grant
Units
Share of common stock				2
Directors Equity Plan \| Stock Awards
Changes
Granted (in shares)		4,305	6,136	6,248
Weighted Average Grant Date Fair Value
Granted (in dollars per unit)		$ 243.61	$ 182.41	$ 166.39