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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, 2020 | Jun. 30, 2019 | Jun. 30, 2020 | Jun. 30, 2019
Business Combinations [Abstract] |  |  |  |
Total revenues | $ 1,586.3 | $ 1,669.4 | $ 3,458.4 | $ 3,670.6
Net earnings attributable to controlling interests | $ 153.9 | $ 111.3 | $ 500.4 | $ 451.0
Basic net earnings per share | $ 0.81 | $ 0.60 | $ 2.63 | $ 2.42
Diluted net earnings per share | $ 0.79 | $ 0.58 | $ 2.58 | $ 2.37

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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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