Stock-Based Compensation Plans - Stock Option Exercises and Restricted Stock Vesting (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Proceeds from stock option exercises	$ 28	$ 53	$ 32
Aggregate intrinsic value	47	76	58
Tax benefit realized upon exercise	10	13	14
Restricted Stock
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Fair value of shares vested	263	199	164
Tax benefit realized upon vesting	65	48	40
Performance Based Restricted Stock
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Fair value of shares vested	8	40	24
Tax benefit realized upon vesting	$ 1	$ 9	$ 3

Amount of tax benefit from vesting of other than stock options granted under share-based compensation arrangement.

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- Definition

Amount of tax benefit from exercise of option under share-based payment arrangement.

+ References

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

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 14
-Subparagraph (a)
-SubTopic 10
-Topic 230
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-14

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

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

+ References

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

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

+ References

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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