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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, 2018 | Jun. 30, 2017 | Jun. 30, 2018 | Jun. 30, 2017
Business Combinations [Abstract] |  |  |  |
Total revenues | $ 1,683.4 | $ 1,525.8 | $ 3,560.7 | $ 3,211.6
Net earnings attributable to controlling interests | $ 116.8 | $ 71.9 | $ 395.8 | $ 306.0
Basic net earnings per share | $ 0.64 | $ 0.40 | $ 2.17 | $ 1.70
Diluted net earnings per share | $ 0.63 | $ 0.40 | $ 2.13 | $ 1.69

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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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