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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, 2020 | Sep. 30, 2019 | Sep. 30, 2020 | Sep. 30, 2019
Business Combinations [Abstract] |  |  |  |
Total revenues | $ 1,850.6 | $ 1,839.2 | $ 5,315.7 | $ 5,515.9
Net earnings attributable to controlling interests | $ 176.6 | $ 126.0 | $ 677.6 | $ 575.9
Basic net earnings per share | $ 0.92 | $ 0.67 | $ 3.55 | $ 3.08
Diluted net earnings per share | $ 0.90 | $ 0.66 | $ 3.47 | $ 3.02

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- Definition The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(3) -URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(2) -URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463 + Details
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