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, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Earnings Per Share [Abstract]
Net income attributable to the parent company	$ (68)	$ 124	$ 30	$ 232
Less: Redeemable noncontrolling interests adjustment to redemption value	0	0	0	0
Net income available to common stockholders - Numerator diluted	(68)	124	30	232
Net income available to common stockholders - Numerator basic	$ (68)	$ 124	$ 30	$ 232
Weighted-average common shares outstanding - Basic	144.0	145.1	143.9	145.3
Employee compensation-related shares, including stock options	0.0	1.4	0.9	1.7
Weighted-average common shares outstanding - Diluted	144.0	146.5	144.8	147.0

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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.

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

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Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities; of income (loss) available to common shareholders.

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Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities, and addition from assumption of issuance of common shares for dilutive potential common shares; of income (loss) available to common shareholders.

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Amount of decrease to net income for accretion of temporary equity to its redemption value to derive net income apportioned to common stockholders.

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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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