Earnings Per Share - Reconciliation of Weighted Average Shares for Basic and Diluted Shares Computations (Detail) - shares shares in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Earnings Per Share [Abstract]
Weighted average shares outstanding for basic net earnings per share	203.7	202.3	203.3	201.7
Effect of dilutive stock options and other equity awards	1.7	1.7	1.6	1.9
Weighted average shares outstanding for diluted net earnings per share	205.4	204.0	204.9	203.6

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

+ References

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-Publisher FASB
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-Topic 260
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- Definition

The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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