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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			9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017		Sep. 30, 2018	Sep. 30, 2017
Earnings Per Share [Abstract]
Net earnings attributable to controlling interests	$ 127.6	$ 111.0	[1]	$ 516.2	$ 409.8	[1]
Weighted average number of common shares outstanding	183.3	180.5		182.4	179.8
Dilutive effect of stock options using the treasury stock method	3.5	2.0		3.3	1.8
Weighted average number of common and common equivalent shares outstanding	186.8	182.5		185.7	181.6
Basic net earnings per share	$ 0.70	$ 0.61	[1]	$ 2.83	$ 2.28	[1]
Diluted net earnings per share	$ 0.68	$ 0.61	[1]	$ 2.78	$ 2.26	[1]
[1] See Note 3 - Revenues from Contracts with Customers for additional information about the restatements related to Topic 606.

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