Capital Stock and Earnings per Share - Reconciliation of Weighted Average Shares for Basic and Diluted Shares Computations (Detail) - shares shares in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Earnings Per Share [Abstract]
Weighted average shares outstanding for basic net earnings per share	203.5	201.9	200.0
Effect of dilutive stock options and other equity awards		1.8	2.4
Weighted average shares outstanding for diluted net earnings per share	203.5	203.7	202.4

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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
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
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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.

+ References

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