Earnings Per Share - Reconciliation of the Numerators and Denominators of the Earnings Per Share Calculations (Details) - USD ($) shares in Millions, $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Earnings Per Share [Abstract]
Net income attributable to the parent company	$ 53	$ 59	$ 98	$ 122
Weighted-average shares outstanding - Basic	146.6	162.1	148.0	163.4
Employee compensation-related shares, including stock options	0.4	1.1	0.4	1.2
Weighted-average shares outstanding - Diluted	147.0	163.2	148.4	164.6

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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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- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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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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