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Stock Option Plans - Stock Options Outstanding and Exercisable (Detail) - $ / shares shares in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2025	Jun. 30, 2025	Dec. 31, 2024
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, minimum (in dollars per share)	$ 79.59
Range of Exercise Prices, maximum (in dollars per share)	$ 347.44
Option Outstanding, Number Outstanding (in shares)	7.0	7.0
Option Outstanding, Weighted Average Remaining Contractual Term (in years)	3 years 10 months 17 days	3 years 10 months 17 days
Option Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 175.86	$ 175.86	$ 148.26
Options Exercisable, Number Exercisable (in shares)	2.4	2.4
Option Exercisable, Weighted Average Exercise Price (in dollars per share)	$ 110.24	$ 110.24
Exercise Prices Range $ 79.59 - $ 79.59
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, minimum (in dollars per share)	79.59
Range of Exercise Prices, maximum (in dollars per share)	$ 79.59
Option Outstanding, Number Outstanding (in shares)	0.4	0.4
Option Outstanding, Weighted Average Remaining Contractual Term (in years)	8 months 12 days
Option Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 79.59	$ 79.59
Options Exercisable, Number Exercisable (in shares)	0.4	0.4
Option Exercisable, Weighted Average Exercise Price (in dollars per share)	$ 79.59	$ 79.59
Exercise Prices Range $ 86.17 - $ 86.17
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, minimum (in dollars per share)	86.17
Range of Exercise Prices, maximum (in dollars per share)	$ 86.17
Option Outstanding, Number Outstanding (in shares)	0.8	0.8
Option Outstanding, Weighted Average Remaining Contractual Term (in years)	1 year 7 months 28 days
Option Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 86.17	$ 86.17
Options Exercisable, Number Exercisable (in shares)	0.8	0.8
Option Exercisable, Weighted Average Exercise Price (in dollars per share)	$ 86.17	$ 86.17
Exercise Prices Range $ 127.90 - $ 127.90
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, minimum (in dollars per share)	127.90
Range of Exercise Prices, maximum (in dollars per share)	$ 127.90
Option Outstanding, Number Outstanding (in shares)	1.2	1.2
Option Outstanding, Weighted Average Remaining Contractual Term (in years)	2 years 8 months 15 days
Option Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 127.90	$ 127.90
Options Exercisable, Number Exercisable (in shares)	0.7	0.7
Option Exercisable, Weighted Average Exercise Price (in dollars per share)	$ 127.90	$ 127.90
Exercise Prices Range $ 156.85 - $ 156.85
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, minimum (in dollars per share)	156.85
Range of Exercise Prices, maximum (in dollars per share)	$ 156.85
Option Outstanding, Number Outstanding (in shares)	0.8	0.8
Option Outstanding, Weighted Average Remaining Contractual Term (in years)	3 years 6 months 29 days
Option Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 156.85	$ 156.85
Options Exercisable, Number Exercisable (in shares)	0.2	0.2
Option Exercisable, Weighted Average Exercise Price (in dollars per share)	$ 156.85	$ 156.85
Exercise Prices Range $ 158.56 - $ 161.14
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, minimum (in dollars per share)	158.56
Range of Exercise Prices, maximum (in dollars per share)	$ 161.14
Option Outstanding, Number Outstanding (in shares)	1.0	1.0
Option Outstanding, Weighted Average Remaining Contractual Term (in years)	3 years 8 months 15 days
Option Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 158.64	$ 158.64
Options Exercisable, Number Exercisable (in shares)	0.3	0.3
Option Exercisable, Weighted Average Exercise Price (in dollars per share)	$ 158.59	$ 158.59
Exercise Prices Range $ 177.09 - $ 202.13
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, minimum (in dollars per share)	177.09
Range of Exercise Prices, maximum (in dollars per share)	$ 202.13
Option Outstanding, Number Outstanding (in shares)	1.0	1.0
Option Outstanding, Weighted Average Remaining Contractual Term (in years)	4 years 8 months 15 days
Option Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 177.76	$ 177.76
Options Exercisable, Number Exercisable (in shares)	0.0	0.0
Option Exercisable, Weighted Average Exercise Price (in dollars per share)	$ 0	$ 0
Exercise Prices Range $ 238.88 - $ 243.54
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, minimum (in dollars per share)	238.88
Range of Exercise Prices, maximum (in dollars per share)	$ 243.54
Option Outstanding, Number Outstanding (in shares)	1.0	1.0
Option Outstanding, Weighted Average Remaining Contractual Term (in years)	5 years 8 months 1 day
Option Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 243.54	$ 243.54
Options Exercisable, Number Exercisable (in shares)	0.0	0.0
Option Exercisable, Weighted Average Exercise Price (in dollars per share)	$ 0	$ 0
Exercise Prices Range $ 337.74 - $ 337.74
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, minimum (in dollars per share)	337.74
Range of Exercise Prices, maximum (in dollars per share)	$ 347.44
Option Outstanding, Number Outstanding (in shares)	0.8	0.8
Option Outstanding, Weighted Average Remaining Contractual Term (in years)	6 years 8 months 1 day
Option Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 337.75	$ 337.75
Options Exercisable, Number Exercisable (in shares)	0.0	0.0
Option Exercisable, Weighted Average Exercise Price (in dollars per share)	$ 0	$ 0

X

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
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The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied.

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The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices.

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The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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

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Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding.

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