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Stock-Based Compensation - Stock Option Exercises and Restricted Stock Vesting (Detail) - USD ($) shares in Thousands, $ in Millions | 6 Months Ended
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Jun. 30, 2025 | Jun. 30, 2024
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items] |  |
Proceeds from stock option exercises | $ 20 | $ 34
Aggregate intrinsic value | 31 | 43
Tax benefit realized upon exercise | $ 7 | $ 7
Number of shares exercised (shares) | 100 | 200
Restricted Stock |  |
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items] |  |
Fair value of shares vested | $ 236 | $ 176
Tax benefit realized upon vesting | $ 58 | $ 43
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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