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Investments - Ownership Percentages and Carrying Value Principal Equity Method Investments (Parenthetical) (Detail) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2023 | Dec. 31, 2022
Schedule of Equity Method Investments [Line Items] |  |
Cumulative unrealized gains on equity securities | $ 28 | $ 74
Cumulative unrealized losses on equity securities | 323 | 205
Sales to equity method investees | $ 83 | $ 51

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