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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, 2025 | Mar. 31, 2024
Business Combinations [Abstract] |  |
Total revenues | $ 3,741.1 | $ 3,285.7
Net earnings attributable to controlling interests | $ 707.6 | $ 611.1
Basic net earnings per share | $ 2.78 | $ 2.81
Diluted net earnings per share | $ 2.73 | $ 2.75

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