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Stock-Based Compensation - Stock Option Exercises and Restricted Stock Vesting (Detail) - USD ($) shares in Millions, $ in Millions | 9 Months Ended
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Sep. 30, 2024 | Sep. 30, 2023
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items] |  |
Proceeds from stock option exercises | $ 44 | $ 26
Aggregate intrinsic value | 60 | 48
Tax benefit realized upon exercise | $ 10 | $ 11
Number of shares exercised (shares) | 0.3 | 0.2
Restricted Stock |  |
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items] |  |
Fair value of shares vested | $ 183 | $ 154
Tax benefit realized upon vesting | $ 45 | $ 36
Number of shares vested (shares) | 0.5 | 0.5
Performance Based Restricted Stock |  |
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items] |  |
Fair value of shares vested | $ 40 | $ 24
Tax benefit realized upon vesting | $ 9 | $ 3
Number of shares vested (shares) | 0.1 | 0.1

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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 + Details
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