Stock Option Plans - Stock Options Outstanding and Exercisable (Detail) - $ / shares shares in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2026	Sep. 30, 2026	Dec. 31, 2025
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)	$ 347.44
Option Outstanding, Number Outstanding (in shares)	7.1	7.1
Option Outstanding, Weighted Average Remaining Contractual Term (in years)	3 years 7 months 28 days	3 years 7 months 28 days
Option Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 195.33	$ 195.33	$ 177.48
Options Exercisable, Number Exercisable (in shares)	2.7	2.7
Option Exercisable, Weighted Average Exercise Price (in dollars per share)	$ 133.96	$ 133.96
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)	0.6	0.6
Option Outstanding, Weighted Average Remaining Contractual Term (in years)	5 months 12 days
Option Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 86.17	$ 86.17
Options Exercisable, Number Exercisable (in shares)	0.6	0.6
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)	1.0	1.0
Option Outstanding, Weighted Average Remaining Contractual Term (in years)	1 year 5 months 15 days
Option Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 127.90	$ 127.90
Options Exercisable, Number Exercisable (in shares)	0.9	0.9
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)	0.7	0.7
Option Outstanding, Weighted Average Remaining Contractual Term (in years)	2 years 4 months 2 days
Option Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 156.85	$ 156.85
Options Exercisable, Number Exercisable (in shares)	0.4	0.4
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)	0.8	0.8
Option Outstanding, Weighted Average Remaining Contractual Term (in years)	2 years 5 months 15 days
Option Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 158.59	$ 158.59
Options Exercisable, Number Exercisable (in shares)	0.5	0.5
Option Exercisable, Weighted Average Exercise Price (in dollars per share)	$ 158.58	$ 158.58
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)	0.9	0.9
Option Outstanding, Weighted Average Remaining Contractual Term (in years)	3 years 5 months 15 days
Option Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 177.68	$ 177.68
Options Exercisable, Number Exercisable (in shares)	0.3	0.3
Option Exercisable, Weighted Average Exercise Price (in dollars per share)	$ 177.74	$ 177.74
Exercise Prices Range $228.20 - $228.20
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, minimum (in dollars per share)	228.20
Range of Exercise Prices, maximum (in dollars per share)	$ 228.20
Option Outstanding, Number Outstanding (in shares)	1.4	1.4
Option Outstanding, Weighted Average Remaining Contractual Term (in years)	6 years 5 months 1 day
Option Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 228.20	$ 228.20
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)	0.9	0.9
Option Outstanding, Weighted Average Remaining Contractual Term (in years)	4 years 5 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 - $347.74
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)	5 years 5 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

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(ii)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 718
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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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(ii)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 718
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-Name Accounting Standards Codification
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-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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

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