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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, 2017 | Mar. 31, 2016
Business Combinations [Abstract] |  |
Total revenues | $ 1,414.4 | $ 1,317.2
Net earnings attributable to controlling interests | $ 55.7 | $ 47.3
Basic net earnings per share | $ 0.31 | $ 0.27
Diluted net earnings per share | $ 0.31 | $ 0.27

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