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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, 2022 | Sep. 30, 2021 | Sep. 30, 2022 | Sep. 30, 2021
Business Combinations [Abstract] |  |  |  |
Total revenues | $ 2,046.0 | $ 2,165.1 | $ 6,560.0 | $ 6,313.3
Net earnings attributable to controlling interests | $ 255.5 | $ 227.1 | $ 980.0 | $ 801.6
Basic net earnings per share | $ 1.21 | $ 1.10 | $ 4.67 | $ 3.99
Diluted net earnings per share | $ 1.19 | $ 1.07 | $ 4.57 | $ 3.90

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