Supplemental Financial Information - Results relating to equity-accounted investees (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Company’s share in income (loss)	$ (2)	$ 7	$ 17
Other results	3	52	36
Results relating to equity-accounted investees	$ 1	$ 59	$ 53

Amount of income (loss) for proportionate share of equity method investee's income (loss).

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