Consolidated Statements Of Comprehensive Income (Loss) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Consolidated Statements Of Comprehensive Income (Loss) [Abstract]
Net loss	$ (345)	$ (426)	$ (5,749)	$ (424)
Other comprehensive income (loss), net of tax	8	(34)	25	36
Comprehensive loss	$ (337)	$ (460)	$ (5,724)	$ (388)

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

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