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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, 2023 | Jun. 30, 2022 | Jun. 30, 2023 | Jun. 30, 2022
Business Combinations [Abstract] |  |  |  |
Total revenues | $ 2,447.6 | $ 2,146.3 | $ 5,250.6 | $ 4,686.8
Net earnings attributable to controlling interests | $ 234.8 | $ 283.4 | $ 724.3 | $ 726.1
Basic net earnings per share | $ 1.09 | $ 1.34 | $ 3.38 | $ 3.45
Diluted net earnings per share | $ 1.07 | $ 1.32 | $ 3.31 | $ 3.38

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