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

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Amount of tax benefit from settlements of RSU and PSU granted under share-based compensation arrangement.

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No definition available.

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Represents the duration of performance targets.

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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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Consists of the right to receive share of common stock.

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No definition available.

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

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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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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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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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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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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	Feb. 28, 2025
Additional share-based compensation disclosures
Total unrecognized compensation cost	$ 61.4
Weighted average recognition period for unrecognized compensation cost (in years)	1 year 7 months 6 days
Restricted stock units (RSUs) and performance stock units (PSUs)
Units
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).	171,578	193,812	305,249
Changes
Unvested at the beginning of the year (in units)	437,239
Granted (in shares)	171,578
Vested (in units)	(233,982)
Cancelled or forfeited (in units)	(47,818)
Unvested at the end of the year (in units)	327,017	437,239
Weighted Average Grant Date Fair Value
Unvested at the beginning of the year (in dollars per unit)	$ 213.06
Granted (in dollars per unit)	289.19	$ 247.9	$ 187.31
Vested (in dollars per unit)	186.89
Cancelled or forfeited (in dollars per unit)	238.85
Unvested at the end of the year (in dollars per unit)	$ 267.96	$ 213.06
Additional share-based compensation disclosures
Tax benefit realized from RSU and PSU settlements	$ 15.3	$ 7.7	$ 8.0
Fair value of vested units	$ 90.2	$ 123.8	$ 147.2
Performance stock units (PSUs)
Units
Vesting period (in years)	3 years	3 years	3 years
Performance target period (in years)	3 years	3 years	3 years
Changes
Granted (in shares)	70,522	84,129	112,451
Vested (in units)	(66,922)
Settled (in shares)				(133,844)
Restricted stock units (RSUs)
Units
Vesting period (in years)	3 years	3 years	3 years
Performance target period (in years)	3 years	3 years	3 years
Share of common stock	1	1	1
Changes
Granted (in shares)	101,056	109,683	192,798
Maximum \| Performance stock units (PSUs)
Units
Share of common stock	2	2	2
Directors Equity Plan \| Stock Awards
Changes
Granted (in shares)	3,542	4,305	6,136
Weighted Average Grant Date Fair Value
Granted (in dollars per unit)	$ 296.56	$ 243.61	$ 182.41