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Business Combinations - Summary of Unaudited Pro Forma Historical Results (Detail) - USD ($) $ / shares in Units, $ in Millions | 3 Months Ended
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Mar. 31, 2026 | Mar. 31, 2025
Business Combination [Abstract] |  |
Total revenues | $ 4,765 | $ 3,740
Net earnings attributable to controlling interests | $ 822 | $ 706
Basic net earnings per share (in dollars per share) | $ 3.20 | $ 2.77
Diluted net earnings per share (in dollars per share) | $ 3.16 | $ 2.72

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