Earnings per Share - Reconciliation of Numerators and Denominators of the Earnings per Share Calculations (Details) - USD ($) shares in Millions, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Earnings Per Share [Abstract]
Net income attributable to the parent company	$ 85	$ 111	$ (68)	$ 98	$ 100	$ 95	$ 124	$ 108	$ 226	$ 427	$ 111
Less: Redeemable noncontrolling interests adjustment to redemption value											(6)
Net income available to common stockholders - Numerator diluted									226	427	105
Net income available to common stockholders - Numerator basic									$ 226	$ 427	$ 105
Weighted-average common shares outstanding - Basic									144.0	145.0	145.1
Employee compensation-related shares, including stock options									1.1	1.5	1.8
Weighted-average common shares outstanding - Diluted									145.1	146.5	146.9