Aggregate number of common shares reserved for future issuance.

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

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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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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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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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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 number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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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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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Weighted-average contractual term remaining for vested portion of option outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Weighted-average contractual term remaining for option award outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Number of share options (or share units) exercised during the current period.

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Stock-Based Compensation - Outstanding Awards (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Exercise price rollforward
Unrecognized compensation cost	$ 16.9		$ 16.9
Weighted average period of unrecognized compensation cost			10 months 24 days
Common Class C
Exercise price rollforward
Shares reserved for issuance	1,300		1,300
Aggregate intrinsic value			$ 22.3	$ 4.5
Common Class C \| 2023 Plan
Options outstanding rollforward
Outstanding beginning balance			2,591
Exercised			(1,333)
Outstanding ending balance	1,258		1,258
Exercisable	1,100		1,100
Exercise price rollforward
Outstanding beginning balance			$ 28.84
Exercised			26.62
Outstanding ending balance	$ 31.2		31.2
Exercisable	$ 30.3		$ 30.3
Weighted average remaining life outstanding			2 years 4 months 24 days
Weighted average remaining life exercisable			2 years 1 month 6 days
Aggregate intrinsic value outstanding	$ 27.0		$ 27.0
Aggregate intrinsic value exercisable	$ 25.0		$ 25.0
Common Class A and B
Options outstanding rollforward
Outstanding ending balance	0		0
RSUs \| Common Class C
Exercise price rollforward
Number of unvested shares	900		900
Grant date fair value	$ 43.42		$ 43.42
Aggregate fair value	$ 2.3	$ 2.2	$ 2.3	$ 2.2