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Derivatives and Hedging - Summary of Realized and Unrealized Gains (Losses) Recognized in Condensed Consolidated Statements of Income on Derivative Instruments (Parenthetical) (Detail) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Gain (loss) on derivatives | $ (127) | $ (25) | $ 10
Seed Investment [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Gain (loss) on derivatives | (230) | (48) | (112)
Deferred Cash Compensation Plans [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Gain (loss) on derivatives | $ 31 | $ 18 | $ 24

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