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Stock-Based Compensation - Stock Option Exercises and Restricted Stock Vesting (Detail) - USD ($) shares in Thousands, $ in Millions | 3 Months Ended
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Mar. 31, 2025 | Mar. 31, 2024
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items] |  |
Proceeds from stock option exercises | $ 18 | $ 16
Aggregate intrinsic value | 28 | 21
Tax benefit realized upon exercise | $ 6 | $ 3
Number of shares exercised (shares) | 100 | 100
Restricted Stock |  |
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items] |  |
Fair value of shares vested | $ 229 | $ 169
Tax benefit realized upon vesting | $ 56 | $ 41
Number of shares vested (shares) | 500 | 400
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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