Share-Based Compensation Plans - Additional Information (Detail) $ / shares in Units, $ in Millions	12 Months Ended
Dec. 31, 2025 USD ($) StockPlan $ / shares shares	Dec. 31, 2024 USD ($) $ / shares	Dec. 31, 2023 USD ($) $ / shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option compensation	$ 8.1	$ 8.5	$ 8.0
Maximum percentage of stock options granted	200.00%
Total compensation cost related to non-vested stock options not yet recognized	$ 17.7
Expected compensation cost recognized over the weighted-average period	1 year 9 months 18 days
Accrued liabilities	$ 152.3	169.1
Weighted Average Grant-Date Fair Value, Vested \| $ / shares	$ 77.8
Share-Based Payment Arrangement, Expense, after Tax	$ 1.0	0.1	0.3
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiration term for stock granted	10 years
Aggregate number of shares of common stock reserved for issuance which can be granted \| shares	2,550,000
Number of stock option plans \| StockPlan	2
Stock option compensation	$ 8.1	8.5	8.0
Employee Stock Option \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of stock vesting period	2 years
Employee Stock Option \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of stock vesting period	5 years
Stock Equivalent Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiration term for stock granted	10 years
Total intrinsic value exercised	$ 13.5	22.4
Accrued liabilities	12.5
Compensation cost	$ 1.8	$ 6.5	$ 13.5
Weighted Average Grant-Date Fair Value, Vested \| $ / shares	$ 107.1	$ 130.3	$ 94.4
Total intrinsic value of options outstanding	$ 34.4
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Intrinsic Value	3.0
ProceedsFromStockOptionsExercised	6.2	$ 12.8
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested in Period, Fair Value	$ 16.4	$ 16.4
Stock Equivalent Units [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of stock vesting period	6 months
Stock Equivalent Units [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of stock vesting period	5 years

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