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Business Combinations - Summary of Unaudited Pro Forma Historical Results (Detail) - USD ($) $ / shares in Units, $ in Millions | 3 Months Ended | 6 Months Ended
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Jun. 30, 2025 | Jun. 30, 2024 | Jun. 30, 2025 | Jun. 30, 2024
Business Combinations [Abstract] |  |  |  |
Total revenues | $ 3,229.5 | $ 2,872.1 | $ 7,031.7 | $ 6,218.5
Net earnings attributable to controlling interests | $ 366.4 | $ 282.4 | $ 1,060.4 | $ 881.2
Basic net earnings per share (in dollars per share) | $ 1.43 | $ 1.29 | $ 4.15 | $ 4.04
Diluted net earnings per share (in dollars per share) | $ 1.41 | $ 1.27 | $ 4.08 | $ 3.96

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