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Share-Based Compensation - Fair Value Options Granted and Assumptions (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Share-based Compensation
Stock options granted, fair value	$ 0.0	$ 0.0	$ 1.8
Intrinsic value of options exercised	150.7	0.2	1.2
Cash received for options exercised	0.3	$ 0.0	$ 2.6
Intrinsic value of exercisable options outstanding	$ 138.6
Stock options granted, weighted average fair value (in dollars per share)			$ 47.84
Stock Options
Share-based Compensation
Shares available for future grant (in shares)	1.1
Assumptions used to determine fair value of options granted
Dividend yield			0.00%
Expected volatility			36.80%
Risk-free interest rate			1.70%
Expected life of options (in years)			5 years 8 months 12 days
Forfeiture rate			0.00%
Stock Options | Minimum
Share-based Compensation
Stock vesting period	3 years
Stock options, expiration period	7 years
Stock Options | Maximum
Share-based Compensation
Stock vesting period	5 years

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- Definition

Represents the expected rate the entity will cancel the stock option awards due to nonfulfillment of certain conditions of equity-based compensation arrangements.

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Amount of cash inflow from exercise of option under share-based payment arrangement.

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The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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