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Stock-Based Compensation - Stock Option Exercises and Restricted Stock Vesting (Detail) - USD ($) shares in Thousands, $ in Millions | 9 Months Ended
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Sep. 30, 2025 | Sep. 30, 2024
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items] |  |
Proceeds from stock option exercises | $ 26 | $ 44
Aggregate intrinsic value | 42 | 60
Tax benefit realized upon exercise | $ 9 | $ 10
Number of shares exercised (shares) | 100 | 300
Restricted Stock |  |
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items] |  |
Fair value of shares vested | $ 245 | $ 183
Tax benefit realized upon vesting | $ 60 | $ 45
Number of shares vested (shares) | 500 | 500
Performance Based Restricted Stock |  |
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items] |  |
Fair value of shares vested | $ 8 | $ 40
Tax benefit realized upon vesting | $ 1 | $ 9
Number of shares vested (shares) | 15 | 100

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