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Earnings Per Share - Computation of Basic and Diluted Net EPS (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Earnings Per Share [Abstract]
Net earnings attributable to controlling interests	$ 334.1	$ 273.7
Weighted average number of common shares outstanding	184.5	181.5
Dilutive effect of stock options using the treasury stock method	3.9	3.5
Weighted average number of common and common equivalent shares outstanding	188.4	185.0
Basic net earnings per share	$ 1.81	$ 1.51
Diluted net earnings per share	$ 1.77	$ 1.48

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