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Stock Option Plans - Additional information (Detail) - USD ($) $ / shares in Units, $ in Millions				3 Months Ended						9 Months Ended
	Mar. 01, 2025	Mar. 01, 2024	May 10, 2022	Sep. 30, 2025	Jun. 30, 2025	Mar. 31, 2025	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Sep. 30, 2025	Sep. 30, 2024
Stock Option Plans [Line Items]
Shares under option, granted (in shares)										800,000
Compensation expense related to stock option grants				$ 12.2	$ 11.6	$ 17.8	$ 11.1	$ 10.5	$ 15.1
Total intrinsic value of options exercised										$ 237.1	$ 215.6
Option
Stock Option Plans [Line Items]
Compensation expense related to stock option grants				12.1			$ 11.1			41.6	$ 36.7
Total unrecognized compensation cost related to nonvested options				$ 152.2						$ 152.2
Weighted average period, years										4 years
Black-Scholes Option Pricing Model
Stock Option Plans [Line Items]
Weighted average fair value per option for all options (in dollars per share)										$ 98.27	$ 69.55
Long Term Incentive Plan
Stock Option Plans [Line Items]
Number of periods options expire										7 years
Long Term Incentive Plan | Full Value Awards
Stock Option Plans [Line Items]
Maximum number of shares issued(in shares)			3,500,000
Stock option granted, share pool (in shares)			13,500,000
Shares available for grant (in shares)				2,100,000						2,100,000
Long Term Incentive Plan | Full Value Awards Up To A Limit
Stock Option Plans [Line Items]
Shares against the pool (in shares)			1
Long Term Incentive Plan | Full Value Awards In Excess Of The Limit
Stock Option Plans [Line Items]
Shares against the pool (in shares)			3.8
Long Term Incentive Plan | Option
Stock Option Plans [Line Items]
Shares available for grant (in shares)				10,200,000						10,200,000
Long Term Incentive Plan | Officer and Key Employees
Stock Option Plans [Line Items]
Shares under option, granted (in shares)	829,000	1,044,000
Stock options granted, exercise percentage, on the third anniversary date of the grant	34.00%	34.00%
Stock options granted, exercise percentage, on the fourth anniversary date of the grant	33.00%	33.00%
Stock options granted, exercise percentage, on the fifth anniversary date of the grant	33.00%	33.00%
Long Term Incentive Plan | Maximum
Stock Option Plans [Line Items]
Minimum exercise price of stock options, percent of fair market value of a share of common stock on the date of grant										100.00%
Long Term Incentive Plan | Maximum | Option
Stock Option Plans [Line Items]
Maximum period for the exercise of stock options										7 years	7 years
Long Term Incentive Plan | Minimum | Executive Officer
Stock Option Plans [Line Items]
Minimum age of employee with not subject to award forfeiture on condition compliance				62 years

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Stock Option Plans [Line Items]

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

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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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