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Stock-Based Compensation Plans - Stock Option Exercises and Restricted Stock Vesting (Detail) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items] |  |  |
Proceeds from stock option exercises | $ 53 | $ 32 | $ 8
Aggregate intrinsic value | 76 | 58 | 9
Tax benefit realized upon exercise | 13 | 14 | 2
Restricted Stock |  |  |
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items] |  |  |
Fair value of shares vested | 199 | 164 | 180
Tax benefit realized upon vesting | 48 | 40 | 42
Performance Based Restricted Stock |  |  |
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items] |  |  |
Fair value of shares vested | 40 | 24 | 50
Tax benefit realized upon vesting | $ 9 | $ 3 | $ 7

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