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Business Combinations - Summary of Unaudited Pro Forma Historical Results (Detail) - USD ($) $ / shares in Units, $ in Millions | 3 Months Ended | 9 Months Ended
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Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022
Business Combinations [Abstract] |  |  |  |
Total revenues | $ 2,500.4 | $ 2,159.0 | $ 7,781.9 | $ 6,877.5
Net earnings attributable to controlling interests | $ 280.1 | $ 255.2 | $ 1,005.7 | $ 982.7
Basic net earnings per share | $ 1.3 | $ 1.21 | $ 4.68 | $ 4.66
Diluted net earnings per share | $ 1.27 | $ 1.18 | $ 4.59 | $ 4.57

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